Vacuum extraction apparatus for cleaning a surface

An apparatus (20) for cleaning a surface (22) includes a clean fluid tank (26) containing a cleaning fluid (46) and configured for delivery of the fluid (46) to the surface (22). The clean fluid tank (26) has a first outer surface (76). A waste fluid tank (30) is coupled with the clean fluid tank (26) and has a second outer surface (78). The second surface (78) abuts the first surface (76) to form a conduit (84) between the first and second surfaces (76, 78), the conduit (84) being in fluid communication with the waste fluid tank (30). Vacuum motors (94) and (108), in communication with the conduit (84), operate to vacuum waste fluid (164) and air (116) into the waste fluid tank (30). The air (116) is expelled from the waste fluid tank (30) via the conduit (84).

TECHNICAL FIELD OF THE INVENTION

The present invention relates to the field of cleaning equipment. More specifically, the present invention relates to vacuum extractors for cleaning carpet.

BACKGROUND OF THE INVENTION

Cleaning carpet and other surfaces enhances the appearance and extends the life of such surfaces by removing the soil embedded in the surface. Moreover, carpet cleaning removes allergens, such as mold, mildew, pollen, pet dander, dust mites, and bacteria. Indeed, regular cleaning keeps allergen levels low and thus contributes to an effective allergy avoidance program.

Vacuum extractors for cleaning surfaces, such as carpet, typically deposit a cleaning fluid upon the carpet or other surface to be cleaned. The deposited fluid, along with soil entrained in the fluid, is subsequently removed by high vacuum suction. This enables the carpet to be almost dry following cleaning, and to be completely dry before mold has time to grow. The soiled fluid, i.e., waste fluid, is then separated from the working air and is collected in a waste tank.

Due to the prevalence of carpeted surfaces in commercial establishments, institutions, and residences, there exists a thriving commercial carpet cleaning industry. In order to maximize the efficacy of the cleaning process, commercial vacuum extractors should be powerful to minimize the time in which the soil entrained cleaning fluid is present in the carpet. Commercial vacuum extractors should also be durable. That is, such a vacuum extractor should be manufactured from durable working parts so that the extractor has a long working life and requires little maintenance. Unfortunately, the cost of a high powered and durable machine can rise significantly if not designed cost effectively.

Individuals working in the carpet cleaning industry are subject to the undesirably loud noise produced by the vacuum motors of conventional vacuum extractors. In addition, some conventional vacuum extractors include fans mounted near internally housed pumps, vacuum motors, and pre-heaters. The fans function to expel air that has been heated by the internal mechanisms from the housing in which they are positioned. Unfortunately, the fans further contribute to the noise produced by conventional vacuum extractors. At best, this noise is annoying. More critically however, continued exposure to noise above 85 decibels (dB), such as that produced by conventional vacuum extractors, can lead to hearing damage and eventual hearing loss at certain frequencies.

Accordingly, what is needed is an apparatus for cleaning a surface that is cost effectively designed while being both high powered and durable. In addition, what is needed is a vacuum extractor in which the noise produced by the vacuum motors is muffled, particularly with high frequency components reduced.

SUMMARY OF THE INVENTION

Accordingly, it is an advantage of the present invention that an apparatus for cleaning a surface is provided.

It is another advantage of the present invention that an apparatus is provided for cleaning a surface by high powered vacuum extraction.

Another advantage of the present invention is that a vacuum extraction apparatus is provided that is durable and cost effectively designed.

Yet another advantage of the present invention is that a vacuum extraction apparatus is provided in which the noise produced by the vacuum motor is muffled.

The above and other advantages of the present invention are carried out in one form by an apparatus for cleaning a surface. The apparatus includes a first tank adapted to contain a fluid and configured for delivery of the fluid to the surface. The first tank includes a first outer surface. A second tank is coupled to the first tank and has a second outer surface. The second outer surface abuts the first outer surface to form a conduit between the first and second outer surfaces, the conduit being in fluid communication with the second tank. A motor is in communication with the conduit and is configured to vacuum the fluid combined with air from the surface for receipt into the second tank. The air is expelled from the second tank via the conduit.

The above and other advantages of the present invention are carried out in another form by an apparatus for cleaning a surface. The apparatus includes a first tank adapted to contain a fluid and a fluid delivery port in fluid communication with said first tank. The fluid deliver port is configured for attachment of a sprayer hose for delivering the fluid from the first tank to the surface. A heater is interposed between the first tank and the fluid delivery port. The apparatus further includes a second tank and a motor in communication with the second tank, the motor being configured to vacuum the fluid from the surface for receipt into the second tank. The motor receives power from an external source, and the apparatus includes means for occasionally switching the power from the motor to the heater to energize the heater.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring toFIGS. 1-3,FIG. 1shows a perspective view of a vacuum extraction apparatus20for cleaning a surface22(FIG. 14) in accordance with a preferred embodiment of the present invention.FIG. 2shows a side view of vacuum extraction apparatus20, andFIG. 3shows a side view of apparatus20in an open position. Apparatus20is configured as a suit-case type carpet cleaner/extractor, and may be utilized in commercial carpet cleaning applications. Vacuum extraction apparatus20includes a base24, a first tank26pivotally coupled to base24via a pivot hinge28, and a second tank30coupled with first tank26. A tool compartment32may be coupled to a rear surface34of first tank26.

Base24includes caster-type front wheels36and large rear wheels38for ease of maneuverability. Internal mechanisms (discussed below) are housed in base24. A first electrical cord40and a second electrical cord42extend into base24to power the internal mechanisms. Base24further includes a fluid delivery port44from which a cleaning fluid, represented by an arrow46, is provided to a cleaning wand (discussed below).

First tank26is adapted to contain cleaning fluid46. Thus, for clarity of understanding, first tank26is referred to hereinafter as clean fluid tank26. Cleaning fluid46may be water or a suitable cleaning solution. Second tank30includes a fluid inlet48to which a vacuum hose of the cleaning wand couples. Second tank30receives a mixture of soiled cleaning fluid and air, represented by an arrow50, at fluid inlet48. Thus, for clarity of understanding, second tank30is referred to hereinafter as waste fluid tank30. Waste fluid tank30may subsequently be emptied via a dump valve52.

In a preferred embodiment, base24, clean fluid tank26, waste fluid tank30, and tool compartment32are formed from a durable plastic material, such as polyethylene. A preferred manufacturing method for base24, clean fluid tank26, and waste fluid tank30is rotational molding. Rotational molding, also known as rotational casting, is a method for molding hollow plastic objects by placing finely divided particles in a hollow mold that is rotated about two axes, exposing it to heat and then to cold. A rotational molding technique and polyethylene are preferred due to their cost effectiveness. However, those skilled in the art will recognize that other manufacturing methodologies, such as blow molding, may be employed, and other materials may alternatively be selected.

Referring toFIG. 4in connection withFIGS. 1-3,FIG. 4shows a rear perspective view of clean fluid tank26. Clean fluid tank26is a generally rounded and substantially closed container having an opening54which is used to fill clean fluid tank26with cleaning fluid46. A control panel56is further positioned on clean fluid tank26. Control panel56includes the appropriate switches for operating the internal mechanisms (discussed below) located in base24. Exemplary switches of control panel56may include a fluid delivery pump switch, vacuum motor switches, and the like, known to those skilled in the art. Clean fluid tank26further includes molded handles58that may be utilized by the operator to maneuver apparatus20. A receptacle60is molded into rear surface34of clean fluid tank26. Receptacle60is adapted to receive a matching protrusion section of tool compartment32.

Referring toFIGS. 5-6,FIG. 5shows a rear perspective view of tool compartment32attachable to clean fluid tank26(FIG. 4), andFIG. 6shows a front perspective view of tool compartment32. As shown inFIG. 5, tool compartment32includes a molded protrusion section62. Protrusion section62seats in receptacle60(FIG. 4) of clean fluid tank26(FIG. 4). Tool compartment32includes an opening63into a cavity64. Tools, gloves, spot cleaner, and the like may be stored in cavity64. In addition, tool compartment32includes a grooved lower section66. As best seen inFIG. 2, first and second electrical cords40and42, respectively, may be wrapped over handles58and around grooved lower section66. Although the internal mechanisms (discussed below) are powered utilizing two power cords, i.e., first and second electrical cords40and42, respectively, it should be understood that the present invention may be alternatively powered utilizing one electrical cord, or more than two electrical cords. Any of the one or more electrical cords may be wrapped over handles58and around grooved lower section66.

Referring toFIG. 7in connection withFIGS. 1-3,FIG. 7shows a front perspective view of waste fluid tank30. Waste fluid tank30is a generally rounded and substantially closed container which may include an opening68which can be used to clean out waste fluid tank30or to pour out any residual fluid remaining in waste fluid tank30. A screw-on lid70located in opening68encloses the interior of waste fluid tank30from the surrounding environment. Fluid inlet48is a generally cylindrical tube that extends from the front upper surface of waste fluid tank30. Fluid inlet48is adapted to be engaged with a vacuum hose (not shown).

Waste fluid tank30further includes externally molded rib members72generally encircling the waste fluid tank30. Since waste fluid tank30is sealed from the surrounding environment, it is subject to significant vacuum from the vacuum motors (discussed below) of apparatus20(FIG. 1). The shape of waste fluid tank30and the inclusion of rib members72provide strength to waste fluid tank30so as to avoid tank collapse when subjected to this vacuum.

The external appearance of waste fluid tank30is also characterized by a molded handle74located near the top front surface of waste fluid tank30. This molded handle74may be utilized as a tie-down location for transporting apparatus20or may otherwise be utilized to facilitate lifting of waste fluid tank30.

Referring toFIGS. 8-10,FIG. 8shows a perspective view of clean fluid tank26revealing a first outer surface76, andFIG. 9shows a perspective view of waste fluid tank30revealing a second outer surface78for abutment with first outer surface76.FIG. 10shows a partial cross-sectional view of the abutment of clean fluid and waste fluid tanks26and30, respectively. The term “outer surface” refers to exposed surfaces of clean fluid and waste fluid tanks26and30when waste fluid tank30is not coupled with clean fluid tank26. However, once tank30is coupled with tank26, first and second outer surfaces76and78, respectively, are no longer exposed.

In an exemplary embodiment, clean fluid tank26has a first channel80formed on first outer surface76. Waste fluid tank30has a second channel82correspondingly formed on second outer surface78. Second channel82mates with first channel80to form a conduit84when waste fluid tank30abuts clean fluid tank26. That is, corresponding tongue and groove members surrounding first and second channels80and82, respectively, seat together to form a fully enclosed conduit84.

A gasket86may optionally be positioned between first and second outer surfaces76and78, about a periphery of first and second channels80and82, to fully seal conduit84from the surrounding environment. However, those skilled in the art will recognize that other means may be employed for sealing conduit84from the surrounding environment, such as a caulking material, adhesive, and/or other such sealants.

Although each of first and second outer surfaces76and78, respectively, of clean fluid tank26and waste fluid tank30have a corresponding one of first and second channels80and82, it should be understood that the channels can take on a variety of shapes to form conduit84. For example, a channel may be formed in only one of first and second outer surfaces76and78, respectively, while the mating one of first and second outer surfaces76and78may be generally smooth, or flat. In addition, the cross-sectional appearance of the channel portion need not be half-circular but may instead be a square channel, a tapered channel, or the like appropriate to the specific shape of the tanks and the location-of the internal mechanisms (discussed below) of vacuum extraction apparatus20.

Conduit84includes a first end88and a second end90. First end88of conduit84is in communication with an interior of waste fluid tank30via a tank outlet92. A first vacuum motor94is coupled to a first underside96of clean fluid tank26. In addition, when apparatus20is assembled, approximately half of first vacuum motor94resides underneath waste fluid tank30. A suction inlet98of first vacuum motor94is in communication with second end90of conduit84.

An air outlet100of first vacuum motor94is in communication with a second conduit102of waste fluid tank30. In an exemplary embodiment, second conduit102is a generally elbow shaped tunnel integrally molded into waste fluid tank30. That is, second conduit102has an inlet104located in second outer surface78, and an outlet (not visible) located on a second underside106of waste fluid tank30. Although second conduit102is shown as being integrally molded into waste fluid tank30, it should be understood that the formation of second conduit102can be shared between clean and waste fluid tanks26and30, respectively, with the object being to keep second conduit102as short as possible.

A second vacuum motor108is coupled to second underside106of waste fluid tank30. Second vacuum motor108has a suction inlet (not visible) in communication with the outlet of second conduit102. An air outlet110of second vacuum motor108is in communication with an exhaust conduit112, and exhaust conduit112includes a muffler114. In a preferred embodiment, muffler114is a non-restrictive muffler for enhanced exhaust flow.

First and second vacuum motors94and108, respectively, operate in series to provide suction to expel air, represented by arrows116, that is carried in mixture50(FIG. 1) from waste fluid tank30. More specifically, when first and second vacuum motors94and108are activated, air116is drawn by the suction of first and second vacuum motors94and108through tank outlet92and into conduit84. Air116thus enters suction inlet98of first vacuum motor94and is exhausted from air outlet100of first vacuum motor88. Air116is then carried through second conduit102to the suction inlet of second vacuum motor108and is expelled from air outlet110of second vacuum motor108through exhaust conduit112and muffler114. Air116is eventually exhausted from muffler114.

Muffler114advantageously serves to quiet the noise from first and second vacuum motors94and108by approximately 3 decibels (dB). By reducing the sound pressure level by 3 dB, the noise “dose” will be cut in half. Accordingly, a decrease of 3 dB significantly reduces the noise level experienced by the operator of apparatus20(FIG. 1) relative to prior vacuum extraction devices thereby reducing the potential for temporary and/or permanent hearing loss.

First outer surface76of clean fluid tank26further includes a first raceway portion115in the form of a molded indentation generally running from the top of first outer surface76to the bottom edge of first outer surface76. Similarly, second outer surface78of waste fluid tank30further includes a second raceway portion117also generally running from the top of second outer surface78to the bottom edge of second outer surface78. When second outer surface78of waste fluid tank30abuts first outer surface76, first and second raceway portions115and117, respectively, combine to form a raceway118. A wiring harness120is positioned in raceway118during assembly of apparatus20(FIG. 1). Wiring harness120electrically couples control panel56with first and second vacuum motors94and108, as well as the other internal mechanisms (discussed below) positioned in base24(FIG. 1).

The formation of conduit84and raceway118between first and second tanks and the integrally formed second conduit102decreases manufacturing and assembly costs relative to prior art devices due to a reduction in the number of discrete components. This reduction in the number of discrete components further results in a related advantage of lower maintenance costs, since there are less parts that have potential for failure.

FIG. 11shows a side sectional view of base24of vacuum extraction apparatus20(FIG. 1) illustrating the internal mechanisms thereof. Base24is substantially hollow, having a cavity122for housing the internal mechanisms of apparatus20. When waste fluid tank30is coupled with clean fluid tank26, and clean fluid tank26is seated on base24(as shown inFIGS. 1-2), first and second vacuum motors94and108reside inside of base24. However, only second vacuum motor108is shown inFIG. 11for clarity of illustration. First and second vacuum motors94and108, mounted on respective first and second undersides96(FIG. 8) and 106(FIG. 9) of clean fluid and waste fluid tanks26and30, may be canted to reduce the depth in which motors94and108extend into cavity122of base24. This saves space in cavity122so that sufficient volume is available for the other mechanisms positioned in base24. In addition, it is desirable that second conduit102be kept as short as possible to achieve better suction between first and second vacuum motors94and108, respectively. The canting of first and second vacuum motors94and108places air outlet100of first vacuum motor94closer to the suction inlet (not shown) of second vacuum motor108so that the length of second conduit102can be minimized.

Apparatus20(FIG. 1) further includes a fluid pump124located within cavity122, and an optional in-line heater126. Fluid pump124includes a pump inlet128in fluid communication with clean fluid tank26via a first feeder line130. A pump outlet132is in fluid communication with in-line heater126via a second feeder line134, and in-line heater126is in fluid communication with fluid delivery port44via a third feeder line136. Accordingly, cleaning fluid46is directed from clean fluid tank26through fluid pump124and in-line heater126, and exits apparatus20(FIG. 1) at fluid delivery port44.

The temperature of cleaning fluid46, the strength of the vacuum produced by first and second vacuum motors94and108operating in series, and the rate of delivery and discharge pressure of cleaning fluid46all contribute to the efficacy of the cleaning procedure performed by apparatus20. Thus, apparatus20may be configured during manufacture of apparatus20to best suit the needs of the user. For example, apparatus20may be adapted to include only one vacuum motor, or more than two vacuum motors operating in series. Moreover, these vacuum motors may be single, dual, or three stage vacuum motors. By way of another example, fluid pump124may be configured to produce one of a number of discharge pressures, for example, 100, 300, 500, and 1200 psi. The optional in-line heater126can be included in apparatus20to rapidly heat the pumped cleaning fluid46before fluid46continues through fluid delivery port44.

In a preferred embodiment, inlet140is larger than an outer diameter of exhaust conduit and exhaust conduit112fits loosely within walled passage138, thus leaving space146surrounding conduit112. As such as air116is exhausted from exhaust conduit112, heated air, represented by an arrow148, within cavity122is drawn into walled passage, where it mixes with air116and is exhausted from apparatus20. Accordingly, no fan is needed to dissipate heat from cavity122of base24, further reducing the noise produced by apparatus20.

FIG. 13shows a block diagram of the internal mechanisms located in base24(FIG. 11). First electrical cord40is electrically coupled to an electrical input146of fluid pump124for providing power from an external source, i.e., conventional wall power, to fluid pump124. Second electrical cord42is electrically coupled to an electrical input148of a switch element150. Power (preferably on a separate circuit from that which first electrical cord40is drawing power) is typically provided to first and second vacuum motors94and108, respectively, when switch element148is set in a first switch position152.

The operating protocol for a vacuum extraction apparatus calls for fluid pump124to be activated to spray cleaning fluid46onto surface22(FIG. 14). Fluid pump124is de-activated, and first and second vacuum motors94and108are then activated to vacuum the deposited cleaning fluid46, along with soil entrained in fluid46. As such, either pump124or vacuum motors94and108may be energized at any given instant, but not all at the same instant.

Switch element150switches to a second switch position154when first and second vacuum motors94and108are de-energized and pump124is energized. Second switch position154enables the power normally provided to first and second vacuum motors94and108to be diverted to in-line heater126, thus energizing heater126. Heater126may be provided with a dedicated power cord. When power is diverted from first and second vacuum motors94and108to heater126and is combined with the power provided from the dedicated power cord (for example, up to 15 Amps per cord), heater126can provide greater heating of fluid46for short intervals. Accordingly, the higher temperature fluid46can increase the cleaning efficacy of fluid46. In one embodiment, switch element150may be a flow switch that switches to second switch position154when sufficient fluid flow is sensed in second feeder line134. In another embodiment, switch element150may sense activation of fluid pump124to switch to second switch position154. In yet another embodiment, switch element150may be manually controlled by an operator via control panel56(FIG. 1).

FIG. 14shows a perspective view of vacuum extraction apparatus20with an attached hose assembly156. Hose assembly156includes a cleaning fluid delivery hose158and a vacuum hose160. A cleaning wand162is coupled to the ends of each of hoses158and160. When fluid pump124(FIG. 11) is activated cleaning fluid46is delivered to surface22via cleaning fluid delivery hose158at cleaning wand162. Conversely, when first and second vacuum motors94and108are activated mixture50of soiled fluid and air is drawn into cleaning wand162and vacuum hose160.

Vacuum extraction apparatus20is shown partially cut away to reveal separation of the working air116from collected waste fluid164. A baffle166is positioned at fluid inlet48of waste fluid tank30. As mixture50is drawn into waste fluid tank30, it is forced into a somewhat narrow passage between baffle166and an interior wall of waste fluid tank30. This configuration of baffle166facilitates the separation of air116from waste fluid164. Air116is subsequently drawn through a conventional screened float shut-off valve168and into conduit84(FIGS. 8-9), and waste fluid164drops into waste fluid tank30. Of course, as known to those skilled in the art, the ball within valve168floats and seals tank outlet92(FIG. 9) when waste fluid tank30is full of waste fluid164.

In summary, the present invention teaches of a vacuum extraction apparatus for cleaning a surface. The dual motors operating in series enable high powered vacuum extraction. The apparatus is durable and cost effectively manufactured through the minimization of discrete components. The number of discrete components is minimized by forming channels in mating surfaces of the clean fluid and waste fluid tanks that once assembled, form a conduit for the passage of air drawn into the waste tank by vacuum. Further advantages are achieved by the inclusion of a muffling device at an output of the vacuum motors and a venting configuration that eliminates the need for a noisy heat dissipating fan.

Although the preferred embodiments of the invention have been illustrated and described in detail, it will be readily apparent to those skilled in the art that various modifications may be made therein without departing from the spirit of the invention or from the scope of the appended claims. For example, the positions of the clean fluid and waste fluid tanks may be switched so that the waste fluid tank is located at the rear of the apparatus and is pivotally coupled to the base, and the cleaning fluid tank is located at the front of the apparatus and is coupled with the waste tank. In addition, the conduits formed by the abutment of the two tanks and/or integrally formed in one of the tanks can take a variety of forms and shapes commensurate with the specific shape of the tanks and the location of the vacuum motor or motors.