Carpet extractor with dual nozzles for dual brushrolls

Information

  • Patent Grant
  • 6533871
  • Patent Number
    6,533,871
  • Date Filed
    Friday, January 12, 2001
    23 years ago
  • Date Issued
    Tuesday, March 18, 2003
    21 years ago
Abstract
A carpet extractor includes a base assembly 1 including a housing 10 which selectively receives a recovery tank 22 for collecting dirty cleaning fluid. A nozzle assembly 67 is mounted to the base housing and provides a fluid flowpath 182 for dirty cleaning fluid from the floor surface to the recovery tank. The nozzle assembly is pivotable from a first position, in which the fluid flowpath communicates with the recovery tank, to a second position, in which the nozzle assembly is spaced from the recovery tank to allow the recovery tank to be removed from the base housing. A second flowpath 138 is formed on the recovery tank between the tank and a nozzle plate 136. The flowpaths have openings 218, 140, respectively, at their lower ends, which are located either side of two longitudinally spaced brushrolls 60, 62. A flap valve 474 selectively closes both flowpaths during above floor cleaning.
Description




BACKGROUND OF THE INVENTION




The present invention relates to the carpet extractor arts. It finds particular application in conjunction with the cleaning of floors and above-floor surfaces, such as upholstery, stairs, and the like, using a cleaning solution.




Carpet extractors of the type which apply a cleaning solution to a floor surface and then recover dirty fluid from the surface are widely used for cleaning carpeted and wooden floors in both industrial and household settings. Generally, a recovery tank is provided on the extractor for storing the recovered fluid. The recovery tank is often bulky in order to store a sufficient quantity of the recovered fluid before emptying. A vacuum source, such as a vacuum pump, is mounted to a base frame of the extractor and applies a vacuum to a nozzle adjacent the floor surface. For ease of manipulating the extractor, the recovery tank may also be mounted to the base. The recovery tank and vacuum source are then generally vertically aligned. This provides a bulky base, which tends to impede access of the extractor to low, overhung spaces, such as beneath chairs, and the like. For cleaning such areas, a low-profile extractor base is desirable. Additionally, in conventional extractors, it is often difficult to remove the recovery tank while the cleaning fluid tank is positioned on the extractor.




The present invention provides a new and improved apparatus which overcomes the above-referenced problems and others, while providing better and more advantageous results.




SUMMARY OF THE INVENTION




In accordance with one aspect of the present invention, a carpet extractor of the type which applies a cleaning fluid to a floor surface and vacuums dirty cleaning fluid is provided. The carpet extractor includes a base housing. A recovery tank is selectively mounted on the base housing, for collecting the dirty cleaning fluid. A nozzle assembly is mounted to the base housing. The nozzle assembly provides a fluid flowpath for dirty cleaning fluid from the floor surface to the recovery tank. The nozzle assembly is movable from a first position, in which the fluid flowpath communicates with the recovery tank, to a second position, in which the fluid flowpath is spaced from the recovery tank to allow the recovery tank to be removed from the base housing.




In accordance with another aspect of the present invention, a carpet extractor of the type which applies a cleaning fluid to a floor surface and vacuums dirty cleaning fluid is provided. The carpet extractor includes a base housing. A recovery tank is selectively mounted on the base housing for collecting the dirty cleaning fluid. A nozzle assembly is mounted to the base housing. The nozzle assembly provides a first fluid flowpath for dirty cleaning fluid from the floor surface to the recovery tank. The nozzle assembly also provides a second fluid flowpath for dirty cleaning fluid from an associated above-floor cleaning tool. A valve selectively at least partially closes the first flowpath.




In accordance with another aspect of the present invention, a method for cleaning a floor surface is provided. The method includes mounting a recovery tank to a base housing and pivoting a nozzle assembly mounted to the base housing to a position in which a fluid flowpath defined within the nozzle assembly fluidly communicates with the recovery tank. The method further includes drawing a vacuum on the recovery tank to draw dirty cleaning fluid through the fluid flowpath and into the recovery tank.




The many benefits and advantages of the present invention will become apparent to those skilled in the art upon reading and understanding the following detailed specification.











BRIEF DESCRIPTION OF THE DRAWINGS




The invention takes form in certain parts and arrangements of parts, preferred embodiments of which will be described in detail in this specification and illustrated in the accompanying drawings which form a part hereof and wherein:





FIG. 1

is a perspective view of an upright carpet extractor according to the present invention;





FIG. 2

, is a side elevational view of a hand held accessory tool for above floor cleaning according to the present invention;





FIG. 3

is an exploded perspective view of the lower portion of the base assembly of the carpet extractor of

FIG. 1

;





FIG. 4

is a perspective view of a lower portion of the carpet extractor base of

FIG. 1

, showing a fan/motor assembly, a cleaning fluid pump and a brushroll motor;





FIG. 5

is an enlarged side sectional view of the extractor base, showing a recovery tank, the float assembly in an open position, and twin brushrolls;





FIG. 6

is an enlarged side sectional view of the extractor base, showing the recovery tank, the float assembly in a closed position and the twin brushrolls;





FIG. 7

is an enlarged, exploded perspective view of the recovery tank and fan/motor cover of

FIG. 1

,





FIG. 8

is an enlarged bottom plan view of the carpet extractor base assembly of

FIG. 1

;





FIG. 9

is an enlarged side sectional view of the recovery tank of

FIG. 1

with the nozzle assembly mounted thereon and a door open ready for above floor cleaning;





FIG. 10

is a greatly enlarged sectional view of an upper end of the recovery tank of

FIG. 9

with a pair of nozzle flowpaths open for carpet cleaning;





FIG. 11

is an enlarged side view of the base assembly of

FIG. 1

with the nozzle assembly pivoted away from the recovery tank to allow removal of the tank;





FIG. 12

is a an exploded perspective view of a directing handle and clean water and cleaning fluid tanks of

FIG. 1

;





FIG. 13

is a perspective view of the extractor of

FIG. 1

with the clean water tank exploded away;





FIG. 14

is a side elevational view of the extractor of

FIG. 1

with the clean water tank exploded away and pivoted as it would be during removal;





FIG. 15

is a schematic view of a cleaning solution distribution pump assembly of the carpet extraction of

FIG. 1

; and





FIG. 16

is a greatly enlarged sectional view of the upper end of the recovery tank as in

FIG. 10

, with the nozzle flowpaths closed by a flap valve for above floor cleaning.











DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS




Referring now to the drawings, wherein the showings are for purposes of illustrating preferred embodiments of the invention only and are not for purposes of limiting the same,

FIG. 1

shows an upright carpet extractor. The extractor includes a base assembly


1


including a base housing


10


. A directing handle assembly


12


is pivotally connected to the base housing


10


for manipulating the base assembly over a floor surface to be cleaned. A tank or reservoir


14


for holding a supply of a concentrated cleaning solution is removably supported on the handle assembly


12


. A second tank or reservoir


15


holds a supply of fresh water. Liquid from the two tanks is mixed and supplied as a dilute cleaning solution to a floor surface or to an optional hand-held accessory tool


16


(

FIG. 2

) for remote cleaning. As shown in

FIG. 1

, the concentrated cleaning fluid tank


14


is seated below the water tank


15


, although it will be appreciated that the positions of the two tanks may be reversed. Alternatively, the two tanks may be positioned side by side or replaced by a single tank, which holds a dilute cleaning solution.




With reference to

FIGS. 3-7

, the base housing


10


includes a lower portion


18


, which may be molded as a single piece from plastic or the like. The lower portion defines an upwardly opening socket


20


, adjacent a forward end, in which a recovery tank


22


is removably seated, and an upwardly opening motor/fan compartment


24


, adjacent a rear end thereof. A motor/fan cover


26


cooperates with the compartment


24


to provide an interior chamber


27


, which houses a vacuum source, such as a motor and fan assembly


28


, for drawing a vacuum on the recovery tank. Between the compartment


24


and the socket


20


is a further upwardly opening compartment


29


, which houses a cleaning solution delivery pump assembly


30


. The motor/fan cover is bolted or otherwise connected to the lower portion of the base housing to enclose the motor and fan assembly and the delivery pump.




With particular reference to

FIG. 3

, the recovery tank socket comprises a rear wall


32


, which extends upwardly to engage a lower end of a forward wall


34


of the motor/fan cover. Side walls


36


,


38


, a forward wall


40


, which curves forwardly, and a base


42


complete the socket. Laterally spaced wheels


54


are journaled into a rearward end


56


of the base housing


10


.




Two agitators, such as rotatable brushrolls


60


,


62


, for agitating the floor surface to be cleaned, are mounted adjacent a forward end


64


of the base housing


10


in a downwardly facing integral cavity


66


. The cavity may be defined by a lower surface of the lower housing portion


18


, or, as will be described in further detail hereinafter, by a nozzle assembly


67


. As shown in

FIG. 6

the two brushrolls are longitudinally spaced, slightly apart, and in parallel. The brushrolls are counterrotated in the directions shown in

FIG. 6

by a single motor-driven belt


68


, best shown in

FIG. 4

, although dual belts are also contemplated. It is also contemplated that a single rotated brushroll or one or more non-motor driven brushes may replace the two mechanically rotated brushrolls.




A motor


70


for driving the belt


68


(see

FIG. 4

) is supported by the lower portion


18


of the base housing in an upwardly facing pocket


72


on the socket base


42


, and is covered by a brushroll motor cover


74


, shown most clearly in

FIG. 7

, which forms a part of the motor/fan cover


26


. As can be seen, the socket base below the motor


70


curves downwards, below the level of the remainder of the generally planar base, and helps to space the brushrolls a correct distance from the floor surface to be cleaned. The belt


68


is carried by a motor shaft


76


and is vertically spaced by two idler pulleys


78


,


80


, which rotate under the influence of the belt. The belt passes from the idler pulleys and around drive wheels


82


,


84


extending from the brushrolls. The motor


70


, belt


68


, idler pulleys


78


,


80


, and brushroll drive wheels


82


,


84


are housed outside, and shielded from the brushroll cavity


66


by a wall


86


, which is an extension of the socket side wall


36


. The wall keeps these mechanical components away from the cleaning liquid within the brushroll cavity and provides for an extended life. The components are covered on their outer sides by a cover member


88


, which is removable to provide access for repairs and maintenance.




As shown in

FIG. 6

, a cleaning solution distributor, such as a, nozzle, or spray bar


90


having spaced openings for releasing the cleaning solution, is mounted within the brushroll cavity


66


, adjacent and parallel to the rearward brushroll


60


. The spray bar


90


directs cleaning solution onto the floor surface via the adjacent rear brushroll


60


. The spray bar is T-shaped, with a downwardly depending wall


92


, which deflects any over-spray onto the adjacent brushroll


60


.




Optionally, a second distributor


94


, mounted within the downwardly facing cavity


66


(or at least with fluid outlets therein) adjacent the forward brushroll


62


, is used to deliver the cleaning solution to the second brushroll.




As shown in

FIG. 6

, a roof


96


of the cavity may be shaped to direct any overflow cleaning solution (i.e., solution which does not fall directly onto either brushroll) downwards, into a gap


100


between the two brushrolls. Specifically, the cavity defines two adjacent tubular cavities


104


,


106


with a generally semicircular profile, which meet above the gap


100


in a downwardly projecting v-shaped cusp


108


. Thus, any cleaning solution which is projected upward into either tubular cavity tends to run downwards towards the v-shaped edge and on to one or other brushroll or into the gap. The rearward brushroll cavity


104


also provides the forward wall


40


for the recovery tank socket


20


and cooperates with the rear wall


32


, sidewalls


36


,


38


and the brushroll motor cover


74


to hold the recovery tank in position on the shelf without undue movement during carpet cleaning.




It will be appreciated that the gap


100


may be sufficiently narrow that bristles


110


of the two brushrolls overlap each other, or may be more widely spaced so that the cleaning solution could potentially drip from the v-shaped edge


108


directly on to the floor. However, in one embodiment, shown in

FIG. 6

, a bar


112


having a triangular-shaped cross section is positioned in the gap between the two brushrolls, adjacent the floor. Fluid dripping through the gap is deflected by the bar


112


onto the adjacent brushrolls. This fluid is then worked into the carpet by the brushrolls, providing an enhanced cleaning action, rather than simply dripping on to the carpet.




With reference now to

FIGS. 5

,


6


, and


7


, the recovery tank


22


includes a curved forward wall


120


, which follows the curvature on the socket forward wall, and a rear wall


122


, which is seated against the rear wall


32


of the socket. A base wall


124


of the recovery tank defines an indent


126


(FIG.


5


), which is shaped to receive the brushroll motor cover. The recovery tank defines an internal chamber


128


for collecting recovered cleaning solution and dirt.




An exterior


129


of the forward wall of the recovery tank defines a depressed zone


130


. When the recovery tank is positioned in the socket


20


, the depressed zone extends through a slot


132


in the socket base (see FIG.


8


), rearward of the brushroll cavity


66


, such that a perforated lip


134


at a lower end of the depressed zone is positioned adjacent the floor surface. A nozzle plate


136


cooperates with the depressed zone


130


to form a first suction nozzle flowpath


138


having an elongated inlet slot or nozzle


140


extending laterally across the width of the nozzle plate and an outlet


142


, formed in the nozzle plate


136


at an upper end


144


of the flowpath


138


(see FIG.


9


). The nozzle cover is adhered to the recovery tank


22


by gluing, sonic welding, or the like, along its peripheral side edges, which sealingly engage adjacent peripheral edges of the depressed zone. Alternatively, the nozzle plate may be removably affixed to the recovery tank by screws, bolts, or other suitable fasteners located adjacent upper and lower ends of the nozzle plate.




The nozzle plate


136


and the depressed zone


130


are formed from a transparent material, such as a conventional thermoplastic, which allows an operator to check that the flowpath


138


is suctioning dirt and cleaning solution effectively and to ensure that the brushrolls


60


,


62


are rotating.




Under the vacuum applied by the motor fan assembly


28


, the first suction nozzle flowpath


138


carries dirty cleaning solution, together with entrained air, away from the carpet rearward of the two brushrolls. Specifically, dirt and cleaning solution from the floor surface to be cleaned are drawn through the nozzle inlet slot


140


into the first suction nozzle flowpath


138


.




With reference now to

FIG. 10

, a recovery tank inlet slot


160


, formed in an upper portion


162


of recovery tank


22


, extends vertically into the recovery tank interior chamber


128


. The recovery tank slot has an opening or inlet


164


is defined in an upper end of the inlet slot


160


and an outlet


165


at its lower end. The opening


164


is in fluid communication with the nozzle flowpath outlet


142


. Arrow A shows the path which the dirty cleaning fluid and air follows as it travels along the first flowpath


138


to the recovery tank. A deflector wall


166


, within the recovery tank is curved forwardly away from the inlet slot. Cleaning solution and entrained air strikes the wall and the solution tends to flow downwardly, into the base of the recovery tank. Some of the solution may bounce forwardly off the deflector wall to strike a curved baffle


168


, defined by an interior surface of the recovery tank forward wall


120


, and from there flows downwardly into the base of the tank. The contact of the fluid with the deflector and baffle helps to separate the cleaning solution from the entrained air. The air is carried through a convoluted pathway through the recovery tank, as indicated by arrow B in FIG.


9


. The deflector wall


166


and baffle


168


thus act as an air-fluid separator, helping to separate the solution from the entrained air. The deflector wall


166


directs the recovered cleaning solution and working air through a roughly 90-degree angle, and the baffle then directs the flow downward into the recovery tank where the recovered solution and dirt are collected in the interior chamber


128


. The deflector wall


166


prevents liquid from traveling directly toward an air discharge outlet


170


of the recovery tank chamber. Since the air has to make several turns before reaching the outlet, any remaining liquid in the air stream tends to drop out.




With reference now to

FIG. 11

, the nozzle assembly


67


is pivotally mounted to the forward end


64


of the base housing


10


and defines a second suction nozzle flowpath


182


therethrough. Specifically, the nozzle assembly is pivotally mounted by rearward projecting flanges


184


, adjacent its lower end


186


, to pivot hooks


188


mounted to the exterior forward end


64


of the lower portion


18


of the base housing (see FIG.


8


). Prior to floor or above floor cleaning, the nozzle assembly


67


is pivoted to an engaged position, in which it is seated on the recovery tank (see FIGS.


5


and


6


). When it is desired to remove the recovery tank from the base for cleaning, the nozzle cover is pivoted in the direction of arrow C, away from the recovery tank, to a disengaged position, shown in FIG.


11


. In the disengaged position, the nozzle assembly lifts the base assembly


1


upwardly at the forward end


64


, so that the bristles are no longer pressing against the carpet surface. Specifically, a projection


190


on the nozzle assembly faces downwardly in the disengaged position, lifting the base housing


10


upward. In this position, the nozzle assembly


67


may be removed completely from the base assembly by pulling the lower end of the nozzle assembly generally downwardly and away from the base, best achieved by first tipping the base slightly using the directing handle


12


. This allows the nozzle assembly to be removed for cleaning.




As is also shown in

FIG. 11

, the roof


96


of the brushroll cavity


66


is defined by the nozzle assembly


67


and thus pivots away from the brushroll cavity with the nozzle assembly to provide ready access to the brushrolls for cleaning.




A tab or handle


192


, which extends upwardly adjacent an upper end


194


of the nozzle assembly


67


, is provided for manipulating the nozzle assembly. A projection


198


, which projects downwardly from the nozzle assembly, is seated in a recess


200


in the recovery tank, thus correctly positioning the upper end of the nozzle assembly on the recovery tank (see FIG.


5


).




A latching member


202


, pivotably mounted to the motor/fan cover


26


, pivots into engagement with a lip or catch


204


on the upper end


194


of the nozzle assembly. The latching member serves to lock the nozzle assembly


67


to the recovery tank


22


and thereby also locking the recovery tank to the base housing


10


. A resilient, V-shaped biasing member


206


, (

FIG. 7

) received rearward of the latch in a slot


208


, biases the latching member to a forward, engaging position. To release the latching member from engagement, the latching member is pivoted rearward, allowing the nozzle assembly to be pivoted forwardly, away from the recovery tank.




When it is desired to remove the recovery tank


22


from the base


1


for emptying or the like, the latching member


202


is released by the operator and the tab


192


on the upper end of the nozzle assembly


67


is grasped by the operator. The nozzle assembly is then pivoted in the direction of arrow C away from the recovery tank. The recovery tank can then be removed from the base.




With reference to

FIGS. 5

,


6


,


7


and


9


-


11


, the nozzle assembly


67


, like the forward end of the recovery tank


22


and nozzle plate


136


, is preferably formed from a transparent plastic or the like. The nozzle assembly may be integrally molded, or may comprise upper and lower members


210


,


211


which are sealed along peripheral edges


214


,


216


(

FIG. 7

) to define the second flowpath


182


therebetween. A laterally extending slotted lip or nozzle opening


218


adjacent a lower end of the nozzle assembly is positioned close to the floor surface. Dirty cleaning solution and entrained air sucked from the floor forward of the front brushroll enters the second flowpath through the nozzle opening


218


and travels up the flowpath


182


, as indicated by arrow D in FIG.


9


.




The second flowpath


182


is also in fluid communication with the recovery tank inlet slot


160


, as shown in FIG.


10


. Specifically, the lower member


211


of the nozzle assembly defines first and second openings


220


,


222


. The first opening


220


is positioned directly over the upper opening


142


in the nozzle plate


136


and provides a fluid pathway between the first flowpath


138


and the second flow path


182


. The second opening


222


is positioned directly over the recovery tank inlet slot


160


. A first stream of dirty cleaning solution and entrained air from the first flow path


138


enters the second flow path


182


through the first opening


220


. The first stream merges with the second stream of air and dirty solution in the second flow path and travels as a single stream through the second opening


222


into the recovery tank inlet slot


160


.




As shown in

FIG. 10

, seals, such as gaskets


226


,


228


,


230


, are provided in suitably positioned cavities


232


,


234


,


236


in the upper surface of the nozzle plate around the first and second openings


220


,


222


to provide a relatively airtight seal between the nozzle plate and the lower member


211


of the nozzle assembly.




An accessory receiving opening


240


in the upper member


210


of the nozzle assembly is closed during floor cleaning by a pivotable door or cover


242


so that all the air and recovered solution entering the upper end


243


of the second nozzle flowpath is directed into the recovery tank chamber


128


. The opening


240


is suitably shaped (e.g., with a bayonet-type fitting) to receive a hose connector


244


for the vacuum hose


246


of the above floor tool, as will be described in further detail hereinafter. A gasket


248


around the opening


240


helps to provide an airtight seal between the door and the nozzle assembly.




As best shown in

FIG. 9

, a cleaning solution discharge opening


250


in a side wall of the recovery tank is used for emptying the interior chamber


128


of collected cleaning solution and dirt. The opening


250


is covered by a cap (not shown) during operation of the extractor.




The air discharge outlet


170


is defined in an upper rearward portion of the recovery tank


22


. When the recovery tank is seated in the socket


20


, the air discharge outlet is in fluid communication with the motor/fan for transporting the dewatered air out of the recovery tank. Optionally, this opening may also be used for emptying the collected dirty cleaning solution and dirt from the tank in place of or in addition to the opening


250


. The upper portion of the recovery tank interior chamber comprises an air separation chamber


258


, which is above the level of the inlet slot


160


to the recovery tank. The air separation chamber has a rearward facing outlet


260


. The outlet is connected with a downwardly extending outlet slot


262


, which projects rearwardly from the recovery tank. The air discharge outlet


170


is positioned at the lower end of the outlet slot


262


. The outlet


170


is seated over a corresponding upper inlet or opening


264


in a vertically extending inlet slot


266


, adjacent the forward wall


34


of the motor/fan housing cover, which communicates with the interior motor/fan chamber


27


. Working air is sucked upward through the recovery tank


22


by the motor and fan assembly into the air separation chamber and is directed downward, through an almost 180-degree turn, into the outlet slot


262


. The air follows the path shown by arrow E into the fan


268


and exits the motor/fan chamber


27


though an opening


270


in a lower wall


272


of the extractor base housing (FIGS.


6


and


8


).




The positioning of the recovery tank


22


and motor and fan assembly


28


provides a low profile extractor base assembly


1


, while maintaining a sizeable capacity for the recovery tank. This allows the base assembly to be wheeled under chairs, beds, and other household furniture or obstructions.




With continued reference to

FIGS. 5

,


6


, and


9


, a float assembly


276


is pivotally mounted within the recovery tank


22


. The float


276


chokes off the flow of working air through the recovery tank chamber


128


when the reclaimed solution in the recovery tank reaches a predetermined level (see FIG.


6


). Specifically, the float includes a flap


278


which closes off a lower entrance


280


to the air separation chamber


258


when the liquid in the recovery tank reaches the predetermined level. The flap


278


is pivotally connected at its forward end to the recovery tank at a pivot point


282


so that it rotates towards the closed position in the direction shown by arrow F as the fluid level rises (see FIG.


5


). An inverted float cup


284


is connected to a support member


286


, which projects downwardly from about the midpoint of the flap


278


. As the liquid level in the recovery tank rises, air is trapped in the float cup and buoys the float cup, and hence the flap, upward. As a result, the flap shuts off the entrance to the air separation chamber rapidly, i.e., moves from an open to the closed position over a narrow change in fluid level, typically of the order of about 1-1.5 cm.




An anti-slosh wall


290


projects vertically upward from the base


124


of the recovery tank and reduces sloshing of the liquid in the tank as the extractor is moved back and forth over the carpet. This helps to stop the float from closing prematurely by maintaining the solution in the tank at a relatively even level. The liquid passes slowly from one side of the wall


290


to the other through restricted openings on either side of the wall (not shown). The float cup


284


rests against the wall when the flap is in the open position (FIG.


5


).




As shown in

FIGS. 5 and 9

, a filter


294


is removably mounted across the air separation chamber outlet. Specifically, the filter is received in a slot


296


formed in the upper wall


162


of the recovery tank, between the air separation chamber


258


and the recovery tank outlet slot


262


. The filter filters particles of dirt from the working air.




With reference now to

FIG. 7

, the filter


294


comprises a sheet


300


of a porous material, such as plastic or foam, which is readily washable or replaceable to prevent the filter from becoming clogged with dirt. For rigidity, the filter sheet is held within a plastic frame


302


. Prior to entering the recovery tank outlet slot


262


, therefore, the working air passes through the filter


300


as shown by arrow B.




With particular reference to

FIG. 6

, the base housing defines an exhaust chamber


306


at the base of the motor/fan chamber


27


. The working air leaves the motor/fan chamber


27


through the exhaust chamber in the direction of the floor surface through the exit slot


270


defined in the base plate


272


.




Louvers


310


(shown in FIG.


3


), formed in the base housing


10


provide an air inlet for drawing in cooling air for cooling the fan motor


312


. A cooling fan


314


, connected to a rear of the motor


312


, may be rotated by the motor to circulate air around the fan motor to keep it cool. Optionally, the cooling air is also used to cool a heater


316


(FIG.


6


), which is used to heat the cleaning solution on its way from the pump


30


to the manifold


90


. In this embodiment, the heater


316


is mounted in a chamber


318


located beneath the motor/fan assembly


28


. The cooling air passes into the chamber and is exhausted via louvers


320


in the base plate


272


(FIG.


8


).




With particular reference to

FIG. 7

, the recovery tank


22


includes a U-shaped carrying handle


324


, which is movable between a storage position (shown in FIG.


7


), in which the recovery tank handle lies flat beneath the nozzle assembly, and a carrying position, in which the recovery tank can be carried away from the base housing for emptying. In the storage position, the handle lies flat adjacent the top


162


of the recovery tank to maintain the sleek, low profile of the base assembly


1


.




The lower and upper handle portions may be used to store tools when not in use. For example, one or more receptacles


359


(see

FIG. 1

) may be provided on the handle for receiving tools.




The wishbone shape of the handle allows for a rigid construction, while minimizing the use of materials. Specifically, the legs


338


,


340


,


342


,


344


are generally semi-cylindrical and open toward the rear. The rear openings may be covered or partially covered by a removable plate


362


to encase electrical wiring and fluid supply tubes. Extra rigidity may be provided by horizontal support members (not shown), vertically spaced down each of the legs. A vacuum hose support


366


is mounted to the rear of the central member


334


or elsewhere on the handle. The vacuum hose


246


for the accessory tool is wound around the support


366


when not in use.




The fresh water supply tank


15


is indented, adjacent a lower end, to define two hook-shaped indented regions


370


,


372


, one on either side of the tank. Two corresponding projections


374


extend inwardly from upper portions


378


,


380


of the legs


342


,


344


and have a cross-shaped cross section. The projections


374


are received within the indented regions


370


,


372


of the fresh water tank. The fresh water tank pivots forwardly around the two projections in the direction of arrow H for removal from the handle assembly (FIG.


14


). It will be appreciated that alternative pivotal corresponding mounting members could be formed on the tank


15


and leg members. For example, projections similar to projections


374


could be formed on the tank with corresponding projection receiving members on the handle legs.




As can be seen from

FIG. 1

, the tank


15


, depending on its size, may project forward and/or rearward of the two leg members, allowing the weight of the tank to be centered between the leg members or in another suitable operating position.




During cleaning a barrier member or latch


382


, mounted to the lower handle portion


332


(or to the upper handle portion


330


) adjacent an upper end of the cleaning solution tank


15


, engages a catch


384


or depression, or otherwise secures the forward face of the tank


15


against falling forwardly off the handle assembly. As shown in

FIG. 12

, the catch is optionally formed in a separate curved retaining wall


385


which slots on to the front of the clean water tank.




A curved retaining member


386


on plate


360


extends rearward from the upper handle portion to support a rear face of the tank


15


.




When it is desired to remove the clean water tank


15


for refilling, the latch


382


is pivoted to a disengaged position. The water tank is then pivoted forwardly to a position in which it can be lifted upwardly and away from the extractor. The water tank is refilled with water (or emptied) via a fill opening


388


near an upper end of the tank, which is then closed with a cap


390


. The water may be tap water, either hot or cold. Optionally, chemical additives may be added to the water, such as a concentrated anti-soiling agent, which is applied to the carpet after cleaning. It is also contemplated that additional soap or precleaning agents may be added to the clean water tank, on occasion, for more concentrated cleaning of heavily soiled areas of carpet.




With particular reference to

FIG. 14

, a water outlet


394


, at the base of the water supply tank


15


, supplies clean water from the tank. A check valve


396


closes off the outlet


394


during transport of the tank


15


. A reservoir valve actuator


398


mounted to the shelf opens the check valve


396


when the tank is seated on the handle assembly, allowing clean water to enter a water supply line


400


.




As shown in

FIG. 12

, the cleaning fluid tank


14


is seated on the shelf


346


and can be removed from the handle


12


, after first removing the clean water tank, for periodic refilling with concentrated cleaning fluid, such as a soap solution. For this purpose, a fill opening


402


is provided in the top of the tank, which is then closed with a cap


404


. Alternatively, the concentrated cleaning fluid tank


14


may be refilled in situ, after the clean water tank has been removed. The concentrated cleaning fluid tank


14


is smaller than the fresh water tank


15


and is preferably refilled about once for every five or six refills of the clean water tank. The respective sizes of the two tanks is partially dependent on the desired concentration of the dilute cleaning solution and the ratio of concentrated cleaning solution to clean water which is used to achieve this. For example, if the ratio of concentrated cleaning solution to water is from about 1:128 to 4:128, a suitably sized concentrated cleaning fluid tank is about 0.6 liters and about 3.8 liters for the clean water tank.




A pickup tube


406


is received in an upper opening


408


of the tank


14


, through which the cleaning solution is withdrawn from the tank. The concentrated fluid tank


14


is thus free of openings on its sides or base through which cleaning fluid could leak on to the carpet.




As shown in

FIG. 14

, the directing handle assembly


12


is pivotally connected to the base housing


10


for movement between an upright position and a working position. Specifically, the first and second splayed leg members include trunnions


409


, adjacent their lower ends, which are pivotally mounted to the base housing


10


(FIG.


12


). As is evident from

FIG. 1

, the recovery tank


22


is removable from the base assembly


1


even in the upright position of the directing handle assembly


12


, facilitating emptying of the recovery tank


22


. In other words, the recovery tank can be lifted vertically by its carrying handle and clears the cleaning fluid tank


14


, clean water tank


15


, and the directing handle assembly


12


. Similarly, the clean water tank


15


and the cleaning fluid tank


14


may be removed when the recovery tank is mounted on the base housing


10


, even when the directing handle is in the upright position.




With reference now to

FIG. 15

, fluid pathways


410


and


412


(which include the supply line


400


and dip tube


406


, respectively) connect the clean water tank and concentrated cleaning fluid tank outlets


394


,


408


, respectively, with the pump assembly


30


in the base housing. The pump assembly


30


provides pressurized dilute cleaning solution for the manifold


90


or accessory tool


16


. The pump assembly includes a housing


416


with a vibrating piston pump


420


mounted therein. Such pumps may be obtained from Siebe Corp (Invensys) of Lamora, Italy. The pump is operated by a master switch


422


(FIG.


13


), mounted on the directing handle, which also operates the motor/fan assembly


28


. Preferably, the pump


420


is run continuously, whenever the extractor is in operation, to maintain dilute cleaning solution under pressure, ready for use when needed. The first fluid pathway


410


carries the fresh water to the pump. The direction of flow in the fluid pathway


410


is maintained by first and second one way check valves


424


,


426


.




The pump includes a piston


428


, driven by a motor


429


. The piston


428


is mounted for reciprocating movement in a vertically extending piston bore


430


connected with a portion


432


of the first fluid pathway


410


between the two check valves. As the piston moves upward, the first check valve


424


opens and water is drawn into the portion


432


of the first pathway. When the piston moves downward, the first check valve closes and the second valve


426


opens, allowing the pressurized fluid to exit the inter-valve portion


432


.




The second fluid pathway


412


(for the concentrated cleaning fluid) is connected with the first fluid pathway


410


upstream of the first check valve


424


. When it is desired to add concentrated cleaning fluid to the water to form a dilute cleaning solution, an electrically operated valve, such as a solenoid valve


434


, in the second fluid line is opened by operation of a switch


436


on the directing handle. The valve


434


may alternatively be a variable valve which adjusts the flow of cleaning fluid therethrough over a range of flow rates. Or, an additional variable flow restrictor may be located in the fluid line


412


, either upstream or downstream of the valve


434


.




When the valve


434


is open, the concentrated cleaning fluid is sucked by the pump into a portion


438


of the second fluid pathway


412


, between the solenoid valve


434


and a T-connection


440


with the first fluid pathway


410


. It will be appreciated that the extractor can be run without the use of concentrated cleaning fluid by closing the valve


434


. This allows, for example, rinsing of a floor surface with clean water to remove remaining dilute cleaning solution therefrom.




As shown in

FIG. 4

, the solenoid valve and pump assembly are readily accessed for repairs and maintenance by removing the motor/fan cover


26


.




In a preferred embodiment, the pump


420


is used to begin mixing the concentrated cleaning fluid with the water in the section


438


. A fluid line


442


connects the upper end of the piston tube


430


and the section


438


of the second pathway


412


. When the piston


428


moves upward, concentrated cleaning fluid is pushed towards the T-connection and enters the water line


410


. As the piston moves downward, more cleaning fluid is drawn into the section


438


. However, the solenoid valve restricts the rate of flow of the concentrated cleaning fluid into the section


438


creating a suction, which causes water to flow into the section


438


from the water line and mix with the incoming cleaning fluid. This action helps to mix the concentrated cleaning fluid and water to provide a relatively homogeneous mixture for the dilute cleaning solution as it exits the second check valve.




It is to be appreciated that other pumping or mixing systems may be used to mix and/or pump the cleaning solution. For example, the cleaning fluid and water may be mixed first in a mixing valve and then fed as a dilute solution to a pump. Or, the pump may be eliminated and a gravity feed system used to carry the concentrated cleaning fluid and water to a mixing valve and thereafter to the manifold


90


. In such a case, a separate pump may be used for the spray attachment and may be operated only as needed to pressurize the solution.




The dilute cleaning solution (or water, if no concentrated cleaning fluid is being used) passes from the second check valve


426


to a T-shaped connector


450


. A first outlet from the T-shaped connector


450


is connected with a first fluid line


452


, which carries the cleaning solution to the manifold


90


. A second outlet from the T-shaped connector


450


is connected with a second fluid line


454


, which carries the cleaning solution to the optional attachment tool


16


. When it is desired to spray cleaning solution on to the carpet or other floor surface being cleaned, a solenoid valve


456


in the fluid line


452


is opened by operating a switch or trigger


458


on the directing handle


12


(FIG.


13


). A further switch


460


on the handle operates the brushroll motor. Thus the major operating components may all be electrically controlled from the directing handle, either by electrical wires carried through the handle, or by radio telemetry.




The pump assembly


30


maintains the dilute cleaning solution under pressure so that the dilute cleaning solution, pumped by the pump, is sprayed out of the apertures in the manifold


90


and on to the brushroll(s) whenever the solenoid valve


456


is open.




A similar solenoid valve may be used for the hand held accessory tool


16


. More preferably, a solution supply hose


462


for the accessory is fitted with a valve actuator


464


(FIG.


2


), which opens a check valve


466


in the second line


454


when connected thereto.




Optionally, a heater


316


, as previously described, heats the water in the fluid line


452


. The heater may be an in-line heater, heating block, heat exchanger, or any other convenient heating system.




With reference to

FIG. 2

, the solution supply hose


462


of the accessory tool


16


delivers cleaning solution to a remote distributor


468


. When it is desired to convert the extractor from the floor cleaning to a remote cleaning mode for cleaning upholstery, stairs, and the like, the brushroll motor


70


is deenergized by tripping the switch


460


. The solution supply hose


462


for the accessory is connected with the check valve


466


. The cover


242


is pivoted away from the opening


240


in the nozzle assembly


67


and the connector


244


of the vacuum hose for the accessory tool is connected to the bayonet fitting on the nozzle assembly.




The vacuum is then directed towards the vacuum hose


246


to draw a vacuum on an inlet nozzle


470


on the accessory tool


16


. For this purpose, a toggle switch


472


(

FIG. 1

) on the recovery tank is pivoted to change the flow from the floor nozzle inlets


140


,


218


to the accessory tool nozzle


470


. The toggle switch


472


moves a flap valve


474


, which simultaneously closes off the first and second flow paths


138


,


182


(

FIGS. 10 and 16

) to a great extent. The flap valve


474


is pivotally mounted to the upper member


210


of the nozzle assembly such that it is positioned within the second suction nozzle flowpath


182


between the first and second openings


220


,


222


in the lower member. The flap valve pivots from the open position shown in

FIG. 10

(floor cleaning) to the closed position shown in

FIGS. 9 and 16

(above-floor cleaning). In the closed position, the flap valve engages a sealing member


476


, which projects into the second suction nozzle flowpath


182


, thereby shutting off, or substantially shutting off both the first suction nozzle flowpath and the second suction nozzle flowpath.




As shown in

FIGS. 5

,


10


, and


16


, the flap valve


474


has a small aperture


478


therethrough, which applies a portion of the vacuum to the first and second suction nozzle flowpaths


138


,


182


when the flap valve


474


is in the closed position. This low suction, approximately 20% of normal suction, serves to reduce the chance for drips of the dirty cleaning fluid to travel back down the suction nozzle flowpaths to the respective nozzle inlets


140


,


218


when the extractor has first been used for floor cleaning. Also, any drips from the spray bar


90


can also be removed from the floor surface on which the extractor is located. The aperture is sized, however, such that the majority of the suction is applied to the above floor tool


16


when the flap valve is in the closed position.




A trigger


480


, at the remote end of the tool hose


442


, is actuated, as required, to allow the cleaning solution, under pressure, to be sprayed through the remote distributor


468


, as shown in FIG.


2


. The vacuum hose


246


is connected at its remote end to the nozzle


470


of the accessory tool


16


. The nozzle may have any desired shape for accessing comers of upholstery, stairs, and the like. Also, a brush (not shown) may be provided adjacent the nozzle, if desired. Dirt and cleaning solution are drawn through the nozzle


470


of the accessory tool


16


by the suction fan and thereafter drawn into the recovery tank


22


through the upper end of the second suction nozzle flowpath


182


.




As shown in

FIG. 16

, the opening


240


for the accessory vacuum hose is longitudinally spaced from the recovery tank inlet slot


160


. Dirty cleaning fluid and entrained air entering the recovery tank follows the path shown by arrow J. A sloping baffle wall


484


, defined by the lower member


211


of the nozzle assembly, beneath the opening


240


, intercepts the incoming fluid and begins the separation of cleaning solution from the entrained air. The fluid is deflected upwardly by the baffle wall


484


and is then drawn into the recovery tank inlet slot


160


. From there, the incoming fluid follows essentially the same path through the recovery tank and the dewatered air travels into the fan chamber as previously described.




It will be appreciated that since the vacuum hose


246


for the accessory tool is connected to the nozzle assembly


67


, rather than to the recovery tank


22


directly, the recovery tank can be removed from the base


10


without first disconnecting the accessory vacuum hose. The nozzle assembly is simply pivoted out of the way, carrying the vacuum hose with it.




The invention has been described with reference to the preferred embodiments. Obviously, modifications and alterations will occur to others upon a reading and understanding of this specification. It is intended to include all such modifications and alterations insofar as they come within the scope of the appended claims or the equivalents thereof.



Claims
  • 1. A carpet extractor which applies a cleaning fluid to a floor surface and vacuums dirty cleaning fluid, the carpet extractor comprising:a base housing; a recovery tank, selectively mounted on the base housing, for collecting the dirty cleaning fluid; and a nozzle assembly, mounted to the base housing, which provides a fluid flowpath for dirty cleaning fluid from the floor surface to the recovery tank, the nozzle assembly being movable from a first position, in which the nozzle assembly overlies at least a portion of the recovery tank and the fluid flowpath communicates with the recovery tank, to a second position, in which the fluid flowpath is spaced from the recovery tank to allow the recovery tank to be removed from the base housing.
  • 2. The carpet extractor of claim 1, further including:a second fluid flowpath for dirty cleaning fluid from the floor surface to the recovery tank.
  • 3. The carpet extractor of claim 1, wherein the recovery tank includes a slot which selectively receives a filter for filtering air of residual dirt before the air exits the recovery tank.
  • 4. The carpet extractor of claim 1, further including a vacuum source, mounted on the base housing, which draws a vacuum on the recovery tank.
  • 5. The carpet extractor of claim 2, further including a latch, mounted to the base housing, the latch engaging the nozzle assembly in the first position.
  • 6. A carpet extractor carpet extractor which applies a cleaning fluid to a floor surface and vacuums dirty cleaning fluid, the carpet extractor comprising:a base housing; a recovery tank, selectively mounted on the base housing, for collecting the dirty cleaning fluid; and a nozzle assembly, pivotally connected to a forward end of the base housing, which provides a fluid flowpath for dirty cleaning fluid from the floor surface to the recovery tank, the nozzle assembly being pivotable between a first position, in which the fluid flowpath communicates with the recovery tank, and a second position, in which the fluid flowpath is spaced from the recovery tank to allow the recovery tank to be removed from the base housing.
  • 7. The carpet extractor of claim 6, wherein the nozzle assembly includes flanges which engage hooks on the base housing, the flanges pivoting around the hooks.
  • 8. The carpet extractor of claim 7, wherein the flanges and hooks are disengageable to allow the nozzle assembly to be completely separated from the base housing.
  • 9. A carpet extractor which applies a cleaning fluid to a floor surface and vacuums dirty cleaning fluid, the carpet extractor comprising:a base housing; a recovery tank, mounted on the base housing, for collecting the dirty cleaning fluid; a nozzle assembly, mounted to the base housing, which provides a fluid flowpath for dirty cleaning fluid from the floor surface to the recovery tank, the nozzle assembly being movable from a first position, in which the fluid flowpath communicates with the recovery tank, to a second position, in which the fluid flowpath is spaced from the recovery tank to allow the recovery tank to be removed from the base housing; and a second fluid flowpath for dirty cleaning fluid from the floor surface to the recovery tank, the second fluid flowpath being defined between an outer surface of the recovery tank and a nozzle plate, the nozzle plate being connected to the recovery tank.
  • 10. A carpet extractor which applies a cleaning fluid to a floor surface and vacuums dirty cleaning fluid, the carpet extractor comprising:a base housing; a recovery tank, selectively mounted on the base housing, for collecting the dirty cleaning fluid; and a nozzle assembly, mounted to the base housing, which provides a fluid flowpath for dirty cleaning fluid from the floor surface to the recovery tank, the nozzle assembly being movable from a first position, in which the fluid flowpath communicates with the recovery tank, to a second position, in which the fluid flowpath is spaced from the recovery tank to allow the recovery tank to be removed from the base housing, the first fluid flowpath and second fluid flowpath meeting adjacent an inlet to the recovery tank so that the dirty cleaning fluid in the first flowpath and the dirty fluid in the second flowpath enter the recovery tank as a single stream.
  • 11. The carpet extractor of claim 10, further including:a valve which selectively at least partially closes both the first flowpath and the second flowpath when the carpet extractor is to be used for above floor cleaning; and an above floor cleaning tool having a vacuum hose which is selectively fluidly connectable with the recovery tank.
  • 12. The carpet extractor of claim 11, wherein the valve is a flap valve which only partially closes the first flowpath and the second flowpath, the flap valve including an aperture through which dirty cleaning fluid may be drawn through the first and second flowpaths even when the valve is closed.
  • 13. A carpet extractor which applies a cleaning fluid to a floor surface and vacuums dirty cleaning fluid, the carpet extractor comprising:a base housing; a recovery tank, selectively mounted on the base housing, for collecting the dirty cleaning fluid; a nozzle assembly, mounted to the base housing, which provides a fluid flowpath for dirty cleaning fluid from the floor surface to the recovery tank, the nozzle assembly being movable from a first position, in which the fluid flowpath communicates with the recovery tank, to a second position, in which the fluid flowpath is spaced from the recovery tank to allow the recovery tank to be removed from the base housing; an above floor cleaning tool having a vacuum hose for carrying dirty cleaning fluid from a surface being cleaned with the tool; and wherein the nozzle assembly defines an accessory opening for receiving a fitting on the vacuum hose, the accessory opening communicating with the recovery tank.
  • 14. The carpet extractor of claim 13, wherein the accessory opening is longitudinally spaced from an inlet which fluidly connects the flowpath with the recovery tank, the nozzle assembly providing a baffle wall between the accessory opening and the inlet which serves to deflect the incoming dirty fluid.
  • 15. A carpet extractor which applies a cleaning fluid to a floor surface and vacuums dirty cleaning fluid, the carpet extractor comprising:a base housing; a recovery tank, selectively mounted on the base housing, for collecting the dirty cleaning fluid; a nozzle assembly, mounted to the base housing, which provides a fluid flowpath for dirty cleaning fluid from the floor surface to the recovery tank, the nozzle assembly being movable from a first position, in which the fluid flowpath communicates with the recovery tank, to a second position, in which the fluid flowpath is spaced from the recovery tank to allow the recovery tank to be removed from the base housing; a latch, mounted to the base housing, the latch engaging the nozzle assembly in the first position, the engagement of the latch with the nozzle assembly locking the recovery tank to the base housing.
  • 16. A carpet extractor which applies a cleaning fluid to a floor surface and vacuums dirty cleaning fluid, the carpet extractor comprising:a base housing; a recovery tank, mounted on the base housing, for collecting the dirty cleaning fluid; a nozzle assembly, mounted to the base housing, which provides a fluid flowpath for dirty cleaning fluid from the floor surface to the recovery tank, the nozzle assembly being movable from a first position, in which the fluid flowpath communicates with the recovery tank, to a second position, in which the fluid flowpath is spaced from the recovery tank to allow the recovery tank to be removed from the base housing; a second fluid flowpath for dirty cleaning fluid from the floor surface to the recovery tank; and first and second longitudinally spaced agitators for agitating the floor surface during cleaning, the first and second flowpaths defining nozzle openings one adjacent each agitator.
  • 17. A carpet extractor which applies a cleaning fluid to a floor surface and vacuums dirty cleaning fluid, the carpet extractor comprising:a base housing; a recovery tank, selectively mounted on the base housing, for collecting the dirty cleaning fluid; a means for drawing suction on the recovery tank; a nozzle assembly, mounted to the base housing, which provides a first fluid flowpath for dirty cleaning fluid from the floor surface to the recovery tank, the nozzle assembly also providing a second fluid flowpath for dirty cleaning fluid from an associated above floor cleaning tool which is selectively connectable therewith; and a valve with an opening which selectively only partially closes the first fluid flowpath, such that the majority of the suction is applied to the above floor cleaning tool.
  • 18. The carpet extractor of claim 17, further including a lid which selectively closes the second fluid flowpath.
  • 19. A carpet extractor which applies a cleaning fluid to a floor surface and vacuums dirty cleaning fluid, the carpet extractor comprising:a base housing; a recovery tank, selectively mounted on the base housing, for collecting the dirty cleaning fluid the recovery tank defining a first flowpath for dirty cleaning fluid from the floor surface to the recovery tank; a means for drawing a vacuum on the recovery tank; a nozzle assembly, mounted to the base housing, which provides a second fluid flowpath for dirty cleaning fluid from the floor surface to the recovery tank; and a valve which selectively at least partially closes the first fluid flowpath.
  • 20. A method for cleaning a floor surface comprising:mounting a recovery tank to a base housing; pivoting a nozzle assembly mounted to the base housing in a first direction from a first position, in which a fluid flowpath defined within the nozzle assembly does not fluidly communicate with the recovery tank, to a second position, in which the fluid flowpath fluidly communicates with the recovery tank; and drawing a vacuum on the recovery tank to draw dirty cleaning fluid through the fluid flowpath and into the recovery tank, thereby cleaning the floor surface.
  • 21. The method of claim 20, further including:after the step of drawing a vacuum, at least partially closing the fluid flowpath; and fluidly connecting a vacuum hose of an above floor accessory tool with the recovery tank.
  • 22. The method of claim 20, further including:pivoting the nozzle assembly in an opposite direction to the first direction such that a projection which extends from a lower end of the nozzle assembly engages with the floor surface, the engagement causing the base housing to pivot away from the floor surface, thereby raising brushrolls mounted to the base housing away from the floor surface.
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