具体实施方式：
[0032]The present disclosure generally relates to a surface cleaning apparatus adapted for wet cleaning and can include a heated fluid delivery system, a liquid delivery system, and/or a recovery system. Aspects of the disclosure relate to an improved surface cleaning apparatus with heated liquid and steam dispensing. According to one aspect of the disclosure, a surface cleaning apparatus is provided with a dual-phase distributor that dispenses heated liquid and steam vapor.
[0033]As used herein, the term “dirt” includes dirt, soil, dust, hair, stains, and other debris, unless otherwise noted.
[0034]As used herein, the term “cleaning fluid” may encompass liquid, steam, or a mixture of both liquid and steam.
[0035]As used herein, the term “heated fluid” includes liquid, steam, or a mixture of both liquid and steam heated to around 100±10° C., alternately about 90 to 100° C., alternatively about 95 to 98° C. The heated fluid may be produced by heating a cleaning fluid with a heat source on board the surface cleaning apparatus. The heated fluid can include at least some liquid and at least some steam, e.g. a liquid phase and a vapor phase. For example, the heated fluid can have a steam quality of around 20 to 30%, alternately about 24%. As used herein, “steam quality” is the proportion of saturated steam in a saturated condensate (liquid) and steam mixture. For example, saturated steam vapor has a steam quality of 100%, and saturated liquid has a steam quality of 0%.
[0036]As used herein, the term “heated liquid” includes a liquid, such as but not limited to water or solutions containing water (like water mixed with a cleaning chemistry, fragrance, etc.), heated to around 100±10° C., alternately about 90 to 100° C., alternatively about 95 to 98° C. The heated liquid can include at least some steam, or substantially not steam. For example, the heated liquid can have a steam quality of around 20 to 30%, alternately about 24%. In other examples, the heated liquid can have a steam quality below 20%, including a steam quality near or at 0%.
[0037]As used herein, the term “unheated liquid” includes a liquid, such as but not limited to water or solutions containing water (like water mixed with a cleaning chemistry, fragrance, etc.), below the temperature of heated liquid, including but not limited to 32 to 55° C. The unheated liquid may or may not be heated by a heat source on board the surface cleaning apparatus. The unheated liquid may have a steam quality of 0%.
[0038]As used herein, the term “steam” includes a liquid, such as but not limited to water or solutions containing water (like water mixed with a cleaning chemistry, fragrance, etc.), at least partially converted to a gas or vapor phase. The liquid can be boiled or otherwise at least partially converted to the gas or vapor phase by heating or mechanical action like nebulizing. The steam can be invisible to the naked eye, in the form of a visible vapor that can be observed by the naked eye, or combinations thereof.
[0039]As used herein, the terms “visible vapor,”“visible steam,” or “visible steam vapor” includes steam that can be observed by the naked eye and is therefore visible to a user of the surface cleaning apparatus.
[0040]The functional systems of the surface cleaning apparatus can be arranged into any desired configuration, such as an upright device having a base and an upright body for directing the base across the surface to be cleaned, a canister device having a cleaning implement connected to a wheeled base by a vacuum hose, a lift-off floor cleaner (e.g., a floor cleaner capable of being used as an upright-type cleaner as well as a canister type cleaner), a portable or hand-held device adapted to be hand carried by a user for cleaning relatively small areas, an unattended surface cleaner, such as an unattended spot cleaning apparatus, or an autonomous/robotic device. At least some of the aforementioned cleaners can be adapted to include a flexible vacuum hose, which can form a portion of a working air path between a nozzle and a suction source.
[0041]FIG. 1 is a schematic view of various functional systems of a surface cleaning apparatus in the form of an extraction cleaner 10. The extraction cleaner 10 can include a fluid delivery system 12 including a source of cleaning fluid 14, a heater 16 for heating the cleaning fluid, and a dual-phase distributor 18 including a phase separator 20 that separates a vapor phase of the heated fluid from a liquid phase thereof. A heated liquid outlet 22 dispenses heated liquid and a steam vapor outlet 24 dispenses steam vapor.
[0042]The fluid delivery system 12 can include other conduits, ducts, tubing, hoses, connectors, valves, etc. fluidly coupling the components of the system 12 together and providing a supply path 26 from the source of cleaning fluid to the dual-phase distributor 18. It is noted that the heated liquid outlet 22 and/or the steam vapor outlet 24 may include a single outlet opening or a plurality of outlet openings that collectively define an outlet.
[0043]The fluid source 14 can stored cleaning fluid in liquid form. The cleaning fluid can comprise one or more of any suitable cleaning fluids, including, but not limited to, water, compositions, concentrated detergent, diluted detergent, etc., and mixtures thereof. For example, the cleaning fluid can comprise water. In another example, the cleaning fluid can comprise a mixture of water and concentrated detergent.
[0044]The fluid delivery system 12 can include a flow controller to control the flow of fluid from the source 14 to the heater 16. In one configuration, the flow controller can comprise a pump 28 which pressurizes the path 26 and controls the delivery of heated fluid to the dual-phase dispenser 18. In one example, the pump 28 can be a centrifugal pump. In another example, the pump 28 can be a solenoid pump.
[0045]In some embodiments, the pump 28 can have multiple speeds and/or flow rates so that a flow rate of cleaning fluid out of the dual-phase dispenser 18 can be varied. The extraction cleaner 10 can have an input control (not shown) that controls the speed and/or flow rate of the pump 28.
[0046]A first conduit 30 leads from the source 14 to an inlet 32 of the pump 28. A second conduit 34 leads from an outlet 36 of the pump 28 to an inlet 38 of the heater 16 to supply cleaning fluid under pressure to the heater 16. A third conduit 44 leads from an outlet 40 of the heater 16 to an inlet 42 of the phase separator 20. The conduits 30, 34, 44 can include one or more ducts, tubing, hoses, etc. fluidly coupling the components together.
[0047]The heater 16 preferably heats the cleaning fluid to about 100° C., where “about” includes ±10° C. This temperature may be the temperature at the outlet 40 of the heater 16. The heater 16 itself may operate at a higher temperature, such as around 130° C. Some heat loss between the outlet 40 of the heater 16 and the phase separator 20 is possible, particularly when the system and its components are heating up and pressurizing. Once a “steady state” is reached, the heated fluid may be about 90 to 100° C., alternatively about 95 to 98° C., measured at the phase separator 20. Some non-limiting examples of a suitable heater 16 include, but are not limited to, a flash heater, a boiler, an immersion heater, and a flow-through steam generator.
[0048]Prior to reaching the phase separator 20, the heated fluid may include cleaning fluid in a mixture of vapor phase and liquid phase. For example, at the heater outlet 40 the heated fluid can have a steam quality of around 20 to 30%, alternately about 24%.
[0049]It is noted that the steam quality of the heated fluid that reaches the phase separator 20 may change over time, for example depending on how long a trigger 52 or other control actuator is depressed. When the trigger 52 is initially depressed, the steam quality may be higher and may decrease until a steady state is reached.
[0050]The phase separator 20 can include a chamber 46 including or otherwise in fluid communication with the inlet 42, a liquid discharge port 48, and a upper vapor discharge port 50. The chamber 46 may be enclosed save for the inlet 42 and two discharge ports 48, 50.
[0051]The phase separator 20 can use gravity to cause denser cleaning fluid, e.g. heated liquid, to settle toward the bottom of the chamber 46 and less dense cleaning fluid, e.g. vapor, to rise toward the top of the chamber 46. The liquid that settles can drain by gravity through the liquid phase discharge port 48. The vapor phase discharge port 50 can be positioned higher than the liquid phase discharge port 48 so that liquid does not exit through the vapor phase discharge port 50. The separated steam vapor is pushed out of the vapor phase discharge port 50 by pressure generated within the heater 16 and, optionally, by pressure generated by the pump 28.
[0052]The liquid phase of the heated fluid dispensed by the heated liquid outlet 22 is substantially in a liquid state, and is preferably within a temperature range of about 90 to 100° C., alternatively about 95 to 98° C. Applying heated liquid within this temperature range is effective at cleaning soft surfaces such as carpet, while not being damaging to typical flooring surfaces. Other temperature ranges are possible, and may depend on one of more of the cleaning fluid, the type of surface to be cleaned (e.g. carpet vs. hard floor, wool carpet vs. nylon carpet), or the type of dirt to be removed from the surface to be cleaned.
[0053]The vapor phase of the heated fluid dispensed by the steam vapor outlet 24 is substantially in a gaseous state, and is preferably within a temperature range of about 90 to 100° C., alternatively about 95 to 98° C. Other temperature ranges for the vapor phase are possible depending on the cleaning fluid. The temperature of the vapor phase of the heated fluid dispensed by the steam vapor outlet 24 is generally similar in temperature to the liquid phase of the heated fluid dispensed by the heated liquid outlet 22, although some variation is possible.
[0054]In some embodiments, the phase separator 20 may integrated with the heated liquid outlet 22 and/or the steam vapor outlet 24. For example, the phase separator 20 may be integrally formed with another portion of the dual-phase distributor 18 as a one-piece part manufactured, for example, via molding or an additive manufacturing process, e.g. a 3-D printing process. Of course, various other methods and/or combinations of methods may also be utilized, including stamping, casting, etc.
[0055]In other embodiments, the phase separator 20 may be remote from a portion of the dual-phase distributor 18 including the heated liquid outlet 22 and/or the steam vapor outlet 24. For example, the phase separator 20 can be located at a distance from the heated liquid outlet 22 and/or the steam vapor outlet 24, and require conduits, ducts, tubing, hoses, etc. routed through the extraction cleaner 10 to fluidly couple the discharge ports 48, 50 to the outlets 22, 24.
[0056]The fluid source 14 can include at least one supply container 56 for storing a supply of cleaning fluid. In yet another configuration, the fluid delivery system 12 can have an additional supply container 58 for storing a liquid cleaning fluid. For example the first supply container 56 can store water and the second supply container 58 can store a cleaning agent such as detergent. The supply containers 56, 58 can, for example, be defined by a supply tank and/or a collapsible bladder. Alternatively, a single container can define multiple chambers for different cleaning fluids.
[0057]In embodiments where multiple supply containers 56, 58 are provided, the system 12 can have with a mixing system for controlling the composition of the cleaning fluid that is delivered to the surface. The composition of the cleaning fluid can be determined by the ratio of cleaning fluids mixed together by the mixing system. In one non-limiting example, the mixing system includes a mixing valve 60 fluidly coupled with an outlet of the second supply container 58, whereby when mixing valve 60 is open, the second cleaning fluid will mix with the first cleaning fluid flowing out of the first supply container 56. By controlling the time that the mixing valve 60 is open, the composition of the cleaning fluid that is delivered to the surface can be selected. Other mixing systems are possible, such as mixing systems with manifolds and controllable orifices.
[0058]In certain embodiments, the extraction cleaner 10 can include a liquid delivery system 62 to deliver liquid to the surface to be cleaned. With both the fluid delivery system 12 and the liquid delivery system 62, the extraction cleaner 10 can selectively deliver unheated liquid, heated liquid and/or steam to the surface to be cleaned.
[0059]Appropriate switches, buttons, actuators, and the like can be provided for user control of the systems 12, 62, including dispensing unheated liquid only, heated liquid and steam only, or a combination of unheated liquid, heated liquid, and steam simultaneously to the surface to be cleaned. For example, the release of cleaning fluid can be controlled by a trigger 52, where depressing the trigger 52 releases cleaning fluid from the dual-phase distributor 18 and the liquid dispenser 64. In some embodiments, release of cleaning fluid from the dual-phase distributor 18 and the liquid dispenser 64 upon depression of the trigger 52 can be mode-dependent. In yet another embodiment, a separate actuator (not shown) controls steam dispensing, while the trigger 52 controls liquid dispensing.
[0060]As shown in FIG. 1, in one embodiment, the liquid delivery system 62 includes at least one liquid dispenser 64 supplied with liquid cleaning fluid from a source of cleaning fluid. The liquid delivery system 62 can share the same fluid source 14 as the fluid delivery system 12, e.g. the supply container 56 or dual supply containers 56, 58. In another embodiment, the extraction cleaner 10 can include a separate supply container (not shown) for storing a cleaning fluid for the liquid delivery system 62.
[0061]Regardless of the source of the cleaning fluid, the liquid delivery system 62 can include other conduits, ducts, tubing, hoses, connectors, valves, etc. fluidly coupling the components of the liquid delivery system 62 together and providing a liquid supply path 66 from the source of cleaning fluid to a liquid dispenser 64. In embodiments where the fluid source 14 is shared, a manifold splitter 68 splits liquid between the steam supply path 26 and the liquid supply path 66. The manifold splitter 68 can include a first outlet in fluid communication with the steam supply path 26, including the heater 16 and the dual-phase distributor 18, and second outlet in fluid communication with a liquid supply path 66, including the liquid dispenser 64.
[0062]The liquid delivery system 62 can include a flow controller for controlling the flow of fluid from the source 14 to the liquid dispenser 64. In one configuration, the flow controller can comprise a pump 70 which pressurizes the path 66 and controls the delivery of liquid cleaning fluid to the liquid dispenser 64. In one example, the pump 70 can be a centrifugal pump. In another example, the pump 70 can be a solenoid pump.
[0063]A first conduit 72 leads from the source 14 to an inlet 74 of the pump 70. A second conduit 76 leads from an outlet 78 of the pump 70 to an inlet 80 of the liquid dispenser 64 to supply liquid cleaning fluid under pressure. The conduits 72, 76 can include one or more ducts, tubing, hoses, etc. fluidly coupling the components together.
[0064]In some embodiments, the pump 70 can have multiple speeds and/or flow rates so that a flow rate of cleaning fluid out of the liquid dispenser 64 can be varied. The extraction cleaner10 can have an input control (not shown) that controls the speed and/or flow rate of the pump 70.
[0065]The liquid dispenser 64 can include at least one liquid outlet 82 for dispensing liquid cleaning fluid to the surface to be cleaned. The at least one outlet 82 can be positioned to deliver liquid cleaning fluid directly to the surface to be cleaned, or indirectly by delivering liquid cleaning fluid onto an agitator (not shown). In one non-limiting example, the at least one outlet 82 delivers liquid cleaning fluid between two horizontally-rotating brushrolls.
[0066]The liquid dispenser 64 can comprise any structure, such as a nozzle, a spray tip, or a manifold, and can comprise one or multiple outlets 82. In one non-limiting example, the liquid dispenser 64 is a spray manifold having multiple outlets 82.
[0067]In certain embodiments, the liquid provided to the liquid dispenser 64 does not pass through the heater 16 and/or is otherwise unheated, and is at the same temperature as the fluid source 14. In other embodiments, the liquid provided to the liquid dispenser 64 passes through a heater (not shown) or is otherwise heated to a temperature that is less than the temperature of the heated liquid dispensed by the heated liquid outlet 22. Such a heater can be located downstream of the fluid source 14 and upstream of the pump 70. In yet another example, the cleaning fluid can be heated using exhaust air from a motor-cooling pathway for a motor/fan assembly.
[0068]In one configuration, the liquid dispenser 64 can dispense liquid cleaning fluid at a rate of 1600 to 2100 ml/min, alternatively about 1740 ml/min. The extraction cleaner 10 can also have a low flow cleaning mode, where the liquid dispenser 64 can dispense liquid cleaning fluid at a rate of 145 to 185 ml/min.
[0069]In one configuration, the dual-phase distributor 18 can dispense cleaning fluid at a rate of 52 to 90 ml/min, alternatively 75 to 80 ml/min. A portion of this is dispensed through the steam vapor outlet 24 as steam vapor, and the remainder is dispensed through the heated liquid outlet 22 as heated droplets. For example, the heated liquid outlet 22 can dispense steam vapor at a rate of 41 to 72 ml/min, alternatively about 60 to 64 ml/min, and the steam vapor outlet 24 can dispense steam vapor at a rate of 10 to 18 ml/min, alternatively at least 12 ml/min, alternatively about 15 ml/min. Alternatively, the dual-phase distributor 18 can dispense cleaning fluid at a rate of about 60 ml/min, with the heated liquid outlet 22 dispensing heated droplets at a rate of about 40-45 ml/min and the steam vapor outlet 24 dispensing steam vapor at a rate of about 15-25 ml/min steam.
[0070]In certain embodiments, the extraction cleaner 10 can include a recovery system 84 to remove liquid and/or dirt from the surface to be cleaned and storing the spent cleaning fluid and dirt. The recovery system 84 can include a suction nozzle 86, a suction source 88 in fluid communication with the suction nozzle 86 for generating a working air stream, and a recovery container 90 for separating and collecting fluid and dirt from the working airstream for later disposal.
[0071]A separator 92 can be formed in a portion of the recovery container 90 for separating fluid and entrained dirt from the working airstream. The suction source 88, such as a motor/fan assembly, is provided in fluid communication with the recovery container 90.
[0072]The suction nozzle 86 can be provided on a base or cleaning head adapted to move over the surface to be cleaned. An agitator 94 can be provided adjacent to the suction nozzle 86 for agitating the surface to be cleaned so that the dirt is more easily ingested into the suction nozzle 86. Some examples of agitators include, but are not limited to, a horizontally-rotating brushroll, dual horizontally-rotating brushrolls, one or more vertically-rotating brushrolls, or a stationary brush. In one non-limiting example, the agitator 94 is two horizontally-rotating brushrolls, and the liquid dispenser 64 delivers liquid cleaning fluid between two horizontally-rotating brushrolls.
[0073]The extraction cleaner 10 can also be provided with above-the-floor cleaning features. An above-the floor cleaning tool (not shown) with its own fluid dispenser and suction inlet can be selectively fluidly coupled to at least one of the delivery systems 12, 62 and to the recovery system 84.
[0074]Electrical components of the extraction cleaner 10, including the heater 16, pumps 28, 70, and suction source 88, are electrically coupled to a power source 96, such as a battery or by a power cord plugged into a household electrical outlet. Appropriate switches, buttons, actuators, and the like can be provided for user control of the heater 16, pumps 28, 70, and suction source 88, thereby controlling the systems 12, 62, 84 of the extraction cleaner 10.
[0075]The application of heated liquid and steam vapor by the dual-phase distributor 18 applies wet heat to the surface to be cleaned. The addition of wet heat introduces elevated energy levels (e.g., heat) to help mobilize various types of dirt and low levels of solvent (e.g., water) to improve dirt transportation away from the surface. Using high temperature liquid, is particularly efficient at removing embedded soils and stains on soft surfaces like carpet. Dirt is freed from the fibers of the soft surface with a combination of chemical and mechanical (e.g. via the agitator 94) interactions, allowing the creation of bonds between the dirt and cleaning fluid. The encapsulated dirt can then be removed from the fibers using suction via the nozzle 86.
[0076]In certain embodiments, the vapor phase of the heated fluid dispensed by the steam vapor outlet 24 is dispensed as visible steam, e.g., a visible vapor that can be observed by the naked eye. Dispensing visible steam offers a visual confirmation to the user that steam is being generated and dispensed by the extraction cleaner 10. Further, since the dual-phase distributor 18 also dispenses heated liquid, the visible steam also offers a visual confirmation to the user that heated liquid is being generated and dispensed by the extraction cleaner 10.
[0077]As least the steam vapor outlet 24 of the dual-phase distributor 18 can be located in front of the suction nozzle 86. With this spatial arrangement, steam vapor is disposed in front of the suction nozzle 86, which can provide visual confirmation that the extraction cleaner 10 is operating. In one embodiment the steam vapor outlet 24 can dispense steam vapor at a rate of 12 to 20 ml/min with the suction source 88 off, and produce visible steam, e.g., a visible vapor that can be observed by the naked eye.
[0078]In some embodiments, the heated liquid outlet 22 and/or the liquid dispenser 64 can be located behind the suction nozzle 86, with the steam vapor outlet 24 located in front of the suction nozzle 86. Since steam vapor does not overly wet the surface to be cleaned, dispensing steam vapor in front of the nozzle 86 provides a visual confirmation that the extraction cleaner 10 is operating without applying a significant volume of fluid to an area of the surface (e.g., near a wall, base board, or furniture) that the suction nozzle 86 cannot reach. Heated and/or unheated liquid is dispensed behind the suction nozzle 86, and can therefore by suctioned up by the nozzle 86.
[0079]FIG. 2 shows the extraction cleaner 10 as an upright extraction cleaner having a housing that includes an upright assembly 100 that is pivotally connected to a base 102 for directing the base 102 across the surface to be cleaned. The extraction cleaner 10 can comprise the various systems and components schematically described for FIG. 1, including the dual-phase fluid delivery system 12, the liquid delivery system 62, and the recovery system 84. The various systems and components schematically described for FIG. 1 can be supported by either or both the base 102 and the upright assembly 100.
[0080]For purposes of description related to the figures, the terms “upper,”“lower,”“right,”“left,”“rear,”“front,”“vertical,”“horizontal,”“inner,”“outer,” and derivatives thereof shall relate to the disclosure as oriented in FIG. 2 from the perspective of a user behind the extraction cleaner 10, which defines the rear of the extraction cleaner 10. However, it is to be understood that the disclosure may assume various alternative orientations, except where expressly specified to the contrary.
[0081]The upright assembly 100 can comprise any type of elongated handle, wand, body, or combination thereof suitable for the purposes described herein, including for a user to maneuver the cleaner 10 over a floor surface to be cleaned. In one embodiment, the upright assembly 100 includes a main support section or frame 104 supporting components of the systems 12, 62, 84, including, but not limited to, the recovery container 90 and the supply container 56. The upright assembly 100 also has an elongated handle 106 extending upwardly from the frame 104 that is provided with a hand grip 108 at one end that can be used for maneuvering the extraction cleaner 10 over a surface to be cleaned. A motor housing 110 is formed at a lower end of the frame 104 and contains the suction source 88 positioned therein in fluid communication with the recovery container 90. Other components of the upright assembly 100 may include, but are not limited to, the heater 16, pumps 28, 70, power source 96, and the like, or any combination thereof.
[0082]The base 102 can comprise any type of base, foot, or cleaning head suitable for the purposes described herein, including being moved over a floor surface to be cleaned. In one embodiment, the base 102 includes a base housing 112 supporting components of the systems 12, 62, 84, including, but not limited to the dual-phase distributor 18, the liquid dispenser 64, the suction nozzle 86, and the agitator 94. Wheels 114 can at least partially support the base housing 112 for movement over the surface to be cleaned. Other components of the base 102 may include, but are not limited to, the heater 16, pumps 28, 70, a motor for driving the agitator 94, a hose, a squeegee, and the like, or any combination thereof.
[0083]A moveable joint assembly 116 can connects the base 102 to the upright assembly 100 for movement of the assembly 100 about at least one axis. In the embodiment shown herein, the upright assembly 100 can pivot up and down about at least one axis relative to the base 102. The joint assembly 116 can alternatively comprise a universal joint, such that the upright assembly 100 can swivel about its longitudinal axis in addition to pivoting relative to the base 102. The upright assembly 100 can pivot, via the joint assembly 116, between an upright or storage position, an example of which is shown in FIG. 2, and a reclined or use position (not shown), in which the upright assembly 100 is pivoted rearwardly to form an acute angle with the surface to be cleaned.
[0084]Wiring and/or conduits can optionally supply electricity, air, liquid and/or steam between the upright assembly 100 and the base 102, or vice versa, and can extend through the joint assembly 116. As such, in some embodiments, a portion of the systems 12, 62, 84 can extend through the joint assembly 116. For example, the steam supply path 26 and the liquid supply path 66 can extend through the joint assembly 116.
[0085]FIG. 3 is a bottom view of a front portion of the base 102, generally showing an underside 118 of the base 102. The agitator 94 of the illustrated embodiment includes dual horizontally-rotating brushrolls, including a forward brushroll 120 and a rearward brushroll 122, and which are located in a brush chamber 124 on the base 102.
[0086]In one embodiment, the brushrolls 120, 122 comprise dowels 126 supporting at least one agitation element. The agitation element can comprise a plurality of bristles 128 extending from the dowel 126. Bristles 128 can be tufted or unitary bristle strips and constructed of nylon, or any other suitable synthetic or natural fiber. In another embodiment, the agitation element can comprise microfiber material provided in addition to or instead of the bristles 128.
[0087]The suction nozzle 86 can include a narrow suction pathway defined between spaced nozzle walls or covers, with an opening forming the nozzle inlet 130 at a lower end thereof. The nozzle inlet 130 is disposed forwardly of the agitator 94. It is noted that nozzle inlet 130 can be single opening extending substantially the entire width of the base 102, or a plurality of smaller openings separated by ribs as shown in FIG. 3, the ribs serving the reinforce the suction nozzle 86.
[0088]The liquid dispenser 64 includes a spray manifold 132 having multiple outlets 82 that deliver liquid cleaning fluid between the brushrolls 120, 122. The spray manifold 132 can have a plurality of spray tips 134 which project downwardly in the area between the brushrolls 120, 122, each spray tip 134 having one outlet 82. In some configurations, the outlets 82 may dispense liquid cleaning fluid onto a portion of the brushrolls 120, 122, in addition to or instead of dispensing liquid cleaning fluid onto the surface to be cleaned underneath the base 102. In another embodiment, a single horizontally-rotating brushroll is provided, and the spray manifold 132 can be disposed in front of, behind, or over the top of the brushroll.
[0089]To distribute heated liquid, the dual-phase distributor 18 can include a heated liquid dispenser 136 comprising multiple heated liquid outlets 22 that deliver heated liquid onto the surface to be cleaned underneath the base 102. The heated liquid dispenser 136 is provided within the interior of the base housing 112, such as within the brush chamber 124, and is disposed in front of the brushrolls 120, 122 and behind the suction nozzle 86. As such, when moving the base 102 in a forward cleaning stoke, heated liquid is dispensed to the surface to be cleaned before the surface is agitated by the brushrolls 120, 122. In another embodiment of the extraction cleaner 10, a single horizontally-rotating brushroll is provided, and the heated liquid dispenser 136 can be disposed in front of the single brushroll.
[0090]The heated liquid dispenser 136 includes a manifold 138 having multiple outlets 22 spaced along its length. The manifold 138 can be transversely-elongated to encourage heated liquid to spread across the length of the heated liquid dispenser 136 to distribute heated liquid evenly to each outlet 22. For example, the manifold 138 may be elongated laterally to span more than 50% of a width of the base 102, alternatively more than 75% of a width of the base 102. In one embodiment, the manifold 138 can be elongated in a direction parallel to a rotational axis X, Y of one or both of the brushrolls 120, 122.
[0091]The manifold 138 can have a plurality of spray tips 140 which project downwardly, each spray tip 140 defining one heated liquid outlet 22. In some configurations, the tips 140, or at least the outlets 22 of the tips 140, are disposed in the brush chamber 124. When viewed from the bottom as shown in FIG. 3, the tips 140 are disposed in a row located in front of the front brushroll 120. As such, on a forward stroke of the base 102, heated liquid is dispensed to the surface to be cleaned before the surface is agitated by the brushrolls 120, 122.
[0092]Alternatively to having a plurality of outlets 22 and/or tips 140, the heated liquid dispenser 136 can have a single, narrow slit-like opening, a plurality of slits or openings of other shapes, including a plurality of openings of uniform or varying size.
[0093]The outlet diameter of the heated liquid outlets 22 may be smaller than the outlet diameter of the unheated liquid outlets 82. In one embodiment, the outlet diameter of the heated liquid outlets 22 is approximately 0.5 mm and the outlet diameter of the liquid outlets 82 may be approximately 0.8 to 1.0 mm. It is noted that the outlet diameter of the outlets 22, 82 may be constant or may vary across the dispensers 64, 136.
[0094]To distribute steam vapor, the dual-phase distributor 18 can include a steam dispenser 142 having a steam manifold 144 positioned at a front of the base 102 and comprising the steam vapor outlet 24 that dispenses steam vapor in front of the suction nozzle 86. In this location, the steam adds wet heat to surface to be cleaned, which can soak into the surface to be cleaned to pre-wet and soften stains and soils. Also, in cases where the dual-phase distributor 18 dispenses visible steam, the visible steam is outputted within a line of sight of the user, thereby offering a visual confirmation