Portable, unattended heating device for stain treatment pad

A system for treating stains on a surface includes a portable, unattended heating device having a housing, a heating plate, and a controller operably coupled with the heating plate, wherein the controller is configured to actuate the heating plate. The system can further include a stain treatment pad wetted with a liquid treating chemistry, and the portable, unattended heating device is adapted to rest on and heat the stain treatment pad to treat a stain, including releasing, transferring and removing the stain from the surface to be cleaned.

BACKGROUND

Cleaning solutions can be used to treat and/or remove stains from soft surfaces, such as fabrics, carpets, rugs and upholstery. Traditional stain treatment typically requires a user to apply a cleaning solution to a surface to be cleaned, wait some predetermined amount of time and then return to remove the soiled and excess liquid. Application can often require the user to scrub the solution into the surface, and the removal step can involve blotting, wiping, rinsing, vacuuming, or some combination thereof. These steps can be labor intensive and expose the user's hands to the soiled and excess liquid. In addition, some of the solution may evaporate from the surface during these steps, diminishing the effectiveness of the solution. Even despite stain treatment, a stain can reappear after treatment if stain residue remains beneath a visible portion of the surface to be cleaned. For example, in some cases, stain residue can remain in carpet backing or padding. If the stain is not permanently and completely removed, it can wick upwardly and eventually reappear on the surface to be cleaned.

Some cleaning solutions are used in an at least partially automated cleaning operation using various surface cleaning apparatus. For example, extractors or deep cleaners are household devices for deep cleaning carpets and other fabric surfaces, such as upholstery. Most carpet extractors comprise a fluid delivery system and a fluid recovery system. These typically clean large areas, and also require an extended drying time for the cleaned area.

Steam devices such as steam mops and handheld steamers typically include at least one tank for storing water that is fluidly connected to a steam generator which heats the liquid to or above the boiling point of liquid to produce steam. The generated steam is directed towards the surface to be cleaned through a distributor nozzle or a manifold. Steam may be applied directly to the surface to be cleaned, or indirectly by use of a cleaning pad attached to the steam device. While these may offer a reduced drying time, many are only effective for light cleaning, sterilizing, or sanitizing, and are ineffective for stain removal.

BRIEF SUMMARY

In one aspect, the invention relates to a cleaning system including a portable, unattended heating device. The portable, unattended heating device includes a housing, a heating plate adapted to heat to a temperature less than the boiling point of water, and a main controller operably coupled with the heating plate, wherein the main controller is configured to actuate the heating plate to heat to a temperature less than the boiling point of water. The system can further include a stain treatment pad wetted with a liquid treating chemistry, and the portable, unattended heating device is adapted to rest on and heat the stain treatment pad to treat a stain on a surface to be cleaned.

DESCRIPTION OF EMBODIMENTS OF THE INVENTION

The invention generally relates to a treating stains on surfaces. In one aspect, the invention relates to treating stains on surfaces using an unattended cleaning device.

Embodiments of the of the present disclosure an unattended and portable heating device that is configured to heat a pre-wetted stain treatment pad to remove tough, set-in stains from carpet and rugs. The heating device, alternatively referred to herein as a pad heater, can comprise a heating plate for warming the stain treatment pad to add heat energy to the chemical reaction and effectuate the stain release, transfer and removal process. The pad heater and stain treatment pad can form a cleaning system used to treat stains on a surface to be cleaned. The cleaning system can include at least one stain treatment pad, or multiple stain treatment pads.

In use, the stain treatment pad is placed on a surface to be cleaned, such as over a stain or other area to be treated, and the pad heater is placed over the pad. The heating plate warms the pad to add heat energy to the chemical reaction between the surface and the treating chemistry of the pad to promote the stain release, transfer and removal process. During the stain release, transfer and removal process, the combination of the treating chemistry of the pad and the heat energy supplied by the pad heater detaches the stain, on a molecular level, from dye sites on the carpet fibers and from the carpet backing. The stain may be partially destroyed by the process, and any remaining stain can be transferred to the stain treatment pad via absorption and then removed together with the pad when the pad is lifted away from the surface to be cleaned. In some cases, the stain may be fully destroyed by the process. In either case, after the process, the stain is no longer visible on the floor surface to the naked eye of the user.

The weight of the pad heater on the pad can also enhance stain treatment. The pad heater can depress the pad onto the surface to be cleaned, which increases contact between the surface and the entire pad, enhancing the delivery of treating chemistry to promote the stain release, transfer and removal process. For example, the weight of the pad heater on the pad can improve the initial deposition of the treating chemistry onto the surface to be cleaned, and can also help absorb stain residue from deeper within the surface to be cleaned; in the case of carpet, from deeper within the carpet and the carpet backing.

The pad heater is adapted to be portable, and can be easily carried or conveyed by hand. The hand-carriable pad heater can have a unitary body provided with a carry handle attached, and is small enough to be transported by one user (i.e. one person) to the area to be treated. One embodiment of the pad heater is shown inFIGS. 1-5. Another embodiment is shown inFIGS. 6-7.

The pad heater is adapted to be unattended, and can perform the majority of its operation without the attendance of a user. To treat a stain, a user places a stain treatment pad on the surface, places the pad heater on the pad, and starts a cleaning cycle using a user interface on the pad heater. The pad heater carries out the rest of heating operation on the pad to treat the stain without requiring further action by the user, and can be left along by the user to complete its operation. Sometime after the heating operation is complete, the user can pick up the pad heater and pad from the surface.

Some stains may require more than one treatment; in this case, multiple heating operations can be performed by the pad heater on the same pad, or new pads can be used for each heating operation.

One embodiment of the pad heater10is shown inFIGS. 1-5, and can include a heating plate12configured to apply heat to a stain treatment pad14, and a main controller comprising a control circuit16and a control panel18coupled with the control circuit16. The main controller is operably coupled with the heating plate12for selectively actuating the heating plate. Optionally, the pad heater10can include a retractable guard assembly20.

The pad heater10includes a housing22defining a unitary portable body that carries the components of the pad heater10, including, but not limited to, the aforementioned heating plate12, control circuit16, control panel18, and optional guard assembly20. The housing22includes a carry handle24, and is small enough to be transported by one user (i.e. one person) to the area to be treated.

The unitary portable body defined by the housing22can include one or more housing parts. In the illustrated embodiment, the housing22includes an upper housing cover26that is coupled with a lower housing base28. The control panel18and carry handle24can be provided on the housing cover26for convenient access by the user. The lower housing base28has a generally flat bottom surface30that is adapted to rest on a surface to be treated, and includes an opening32that is aligned with the heating plate12such that the heating plate12can engage the stain treatment pad14.

The heating plate12can have a flat heating surface34configured to directly engage the stain treatment pad14and transfer heat to the stain treatment pad14. Heat can be transferred to the heating surface34by any combination of conduction, convection, and/or radiation. In the illustrated embodiment, the heating plate12can comprise a heating element such as a heater tube36that conducts heat to the heating surface34. In yet another configuration, the heat source for the pad heater10can comprise a water-activated, self-heating exothermic cartridge forming the heating plate.

The heating plate12further includes a temperature controller38that receives signals from the main controller via the control panel18, and controls the heater tube36, or other heat source, to maintain a preset temperature, and a thermal cutoff40that interrupts electric current when heated to a specific temperature, such as a temperature above the preset temperature. For example, the temperature controller38can include thermostats in the heating plate12that can limit the temperature of the heating plate12to 210° F. (about 99° C.) or less. The thermal cutoff40can open at a higher temperature (ex: above 210° F.) and re-close when the temperature drops. The thermal cutoff40can be configured to automatically reset after the temperature drops, or may be manually resettable.

The pad temperature and temperature of the surface being cleaned will be lower than the temperature of the heating plate12due to heat loss. In some tests of the pad heater10on carpet, the temperature at the carpet was as low as 158° F. (70° C.) when the heating plate12was heated to 210° F. These temperatures are much lower than for a conventional steam mop or steam iron, which are both configured to heat water to its boiling point (100° C./212° F.) to generate steam, and generally apply that steam directly to a surface to be cleaned. Conversely, the heating plate12does not generate steam and does not heat the surface to as high a temperature.

Limiting the heating plate12to 210° F. (about 99° C.) or less and the carpet temperature to around 158° F. (70° C.) may be preferred in some applications since higher temperatures can cause dye in carpet fibers to be removed or transferred to the pad, along with the stain—resulting in a localized area of fading or lightening on the carpet.

The heating plate12can be secured within the housing22, such as by being secured with the base28. The heating surface34is aligned with the opening32in the housing base28and that heating surface34is flush with the flat bottom surface30of the base28. An insulator42can be positioned between the base28and the heating plate12to prevent the passage of heat outside the heating plate12.

In one embodiment, the heating plate12comprises a square aluminum plate having sides approximately 4½ inches long and a thickness of about ¼ inch. Alternative sizes and shapes for the heating plate12are also possible. For example, the size and shape can be dependent on the stain treating pad14, with the heating plate12being dimensioned according to the dimensions of the pad14. The surface area of the heating plate12may be slightly larger than or slightly smaller than the surface area of the pad14. Alternate heating plate materials can comprise steel, stainless steel, or ceramic, for example.

The pad heater10can be powered by a power source. For example, the heating plate12can be powered by electricity, via a power cord44. The power cord44can be attached to the housing22by a strain relief46. A cord wrap48can be provided on the housing22for storing the power cord44when the pad heater10is not plugged in. Alternatively, the power source for the pad heater10can be a rechargeable battery for powering the heating plate12, and may be cordless.

Referring toFIG. 3, the control circuit16can comprise a timer circuit or time delay relay circuit, for example which can incorporate various components such as a printed circuit board (PCB) comprising transistors, capacitor(s), diodes, LEDs, and/or integrated circuits. The PCB50can be integrated with the control panel18, and the PCB50can include an on/off power switch52, and at least one indicator54, such as one or more LEDs, to show when the pad heater10and/or heating plate12is operating and when the cleaning cycle is complete. A push button56or other actuator on the control panel18is used to initiate operation of the timer circuit and the cleaning cycle, and will close the power switch52when actuated. The PCB50is configured to cycle through at least one cleaning cycle when the push button56is pressed to close the power switch52. The control panel18can further include at least one opening or window58for viewing the at least one indicator54. The control panel18and PCB50can be seated in a controller mount60on the housing cover26.

Referring toFIGS. 2, 4 and 5, the optional retractable, spring biased guard assembly20automatically shields the user (and anything else) from the heating plate12when the pad heater10is lifted away from a surface to be cleaned. A tether62having a grip64, or other user-engageable actuator, is coupled with a retractable cover or guard66that is normally biased to cover the heating plate12by a biasing mechanism, as shown inFIG. 4. Pulling the tether grip64away from the housing22retracts the guard66and exposes the heating plate12, as shown inFIG. 5. If the pad heater10is picked up by the handle24or otherwise moved from the normal operation position, where the heating plate12is against a surface as shown inFIG. 5, the guard66will automatically cover the heating plate12.

The tether62can be coupled to the rotatable guard66by a pin68or other suitable attachment and can follow a guard guide70provided within the housing22. The guard guide70can project upwardly from one side of the base28and curve toward the center of the housing22. A tether opening72for the tether62can be provided in the housing cover26, on a side opposite that of the guard guide70. The tether62extends between a first end attached to the guard66by the pin68, into the housing22and around the guard guide70, and out of the housing22at the tether opening72to a second end attached to the grip64.

The guard66can be rotatably mounted to the housing22of the pad heater10. In the illustrated embodiment, the rotatable coupling between the guard66and housing22includes rotational shafts74provided on the guard66that are received in cradles76provided on the base28. Guard mounts78are attached to the cradles76over the rotational shafts74to affix the guard66to the base28for rotational movement about an axis defined by the shafts74.

The biasing mechanism can be one or more torsion springs80mounted between the rotational shafts74of the guard66and the base28. As illustrated, torsion springs80are provided for each rotational shaft74. Alternatively, the biasing mechanism can be a constant force spring coupled between the guard66and the housing22.

The guard66can include a support portion82on which the pad heater10can rest, as shown inFIG. 3. The support portion can include a substantially flat base84that can reduce tipping of the pad heater10. An opening86in the base28is sized so that the entire guard66, including the support portion82, can retract through the opening86and into an interior88of the housing22, as shown inFIG. 5.

Another embodiment of the pad heater10is shown inFIGS. 6-7, and can include at least some or all of the features described above for the embodiment shown inFIGS. 1-5. The second embodiment of the pad heater10includes outboard feet90on the lower portion of the housing22, rather than a support portion on the guard66, which may improve balance and reduce tipping of the pad heater10. When the retractable guard66is closed, as shown inFIG. 6, the pad heater10can securely rest in a tipped orientation on two of the feet90and the guard66. When the retractable guard66is open, as shown inFIG. 7, the pad heater10can securely rest on all of the feet90.

It is noted that the embodiments of the pad heater10shown herein are tankless, and do not include an on-board supply of cleaning fluid or fluid delivery system. This can reduce the weight, size, and cost of the pad heater10in comparison to other conventional cleaning apparatus directed at stain treatment, making the portable pad heater10light-weight, compact, portable and less expensive.

The stain treatment pad14for use with any embodiments of the pad heater10disclosed herein can include a moisture-absorbent pad that can take up or receive, by chemical or molecular action, moisture and stain particles from the surface to be cleaned. The pad14is schematically represented inFIG. 5, and can comprise a substrate material92pre-wetted with a cleaning composition or treating chemistry94. The substrate material92can comprise single or multiple layers and a variety of materials, such as cellulose, cellulose fiber, cellulose fluff, superabsorbent polymer (SAP), micro-fiber, terry cloth, non-woven fiber sheets and combinations thereof. Additionally, optional top and/or bottom layers of the substrate material92can comprise polyethylene, polypropylene, polyester, or combinations thereof and can be micro-perforated for distributing and absorbing fluids to and from the absorbent substrate. The stain treatment pad14for use with any embodiments of the pad heater10disclosed herein can be individually sealed prior to use, such as in a foil package.

The pad14can be pre-wetted by a manufacturing process whereby dry pads of substrate material92are inserted into unsealed foil packages having an upper open end. A predetermined volume of liquid is added to the open package to saturate the dry pad. After the liquid filling operation, the foil package is sealed by a conventional heat seal process.

In one embodiment, the pad14can be pre-wetted with a mixture of water, hydrogen peroxide, and sodium lauryl sulfate (SLS). In other embodiment of the pad, SLS can be replaced by a substitute comprising other anionic surfactants or subsets thereof, such as sodium “R” sulfate salts, where R=C8-C18, or alternatively, replacing the sodium ion with ammonium, magnesium, or triethanolamine (TEA), i.e. ammonium lauryl sulfate (ALS), magnesium lauryl sulfate, or TEA-lauryl sulfate. A fragrance can be included in any embodiment of the cleaning composition described herein.

Some examples of suitable stain treatment pads for use with the various embodiments of the pad heater10disclosed herein can be used are disclosed in U.S. Patent Application Publication No. 2013/0318725, published Dec. 5, 2013, which is incorporated herein by reference in its entirety.

In another embodiment, the pad heater10can be used with the BISSELL Stomp'n Go® Pad for Carpet Stain Removal (Model 96Q9 W).

In another embodiment, a dry or unwetted pad of substrate material92can be wetted with treating chemistry94by the user just prior to use of the pad heater10. For example, an unwetted pad can be placed over a stain, and a treating chemistry can be sprayed or otherwise applied to the pad prior to placing the pad heater over the stain. The treating chemistry can also be applied to the pad prior to placing it on the stain.

With reference toFIG. 8, a cleaning cycle100of any embodiments of the pad heater10disclosed herein may be selected using the control panel18on the pad heater10and can include the following timing sequence: an initial dwell period102(ex: 5 minutes) in which the pre-wetted pad14dwells on the surface to be cleaned and the heating plate12is “off” or de-actuated; a heating period104(ex: 1 minute) in which the heating plate12is “on” or actuated, and heat energy is added to the pad14; and a final dwell period106(ex: 5 minutes) in which the heating plate12is “off” but contains a decreasing amount of residual heat. The total cycle time is the initial dwell period102plus the heating period104plus the final dwell period106(ex: 11 minutes).

Upon initiating the cycle100, the timer circuit opens, which disconnects power to the heating plate12for a pre-determined dwell period at102while the pre-wetted pad14dwells on the surface to be cleaned and saturates the stain with treating chemistry. During this period, the heating plate12is “off” and the pad heater10indicates a cleaning cycle is in process, for example by illuminating one of the LED indicators54on the control panel18. Also during this period, the weight of the pad heater on the pad can increase the amount of treating chemistry deposited from the pad14onto the surface to be cleaned.

After the initial dwell period102, the timer circuit closes and connects power to a heating element within the heating plate12, for example the heater tube36. The heating plate12is energized for the pre-determined heating period at104to raise the temperature of the heating plate12to a predetermined value. Heat energy is added to the stain treatment pad14via the heating plate12at a 210° F. or less thermostat setting.

After the heating period104, the timer circuit opens and disconnects power to the heating plate12. Power to the heating plate12remains disconnected for a final, pre-determined dwell period at106while residual heat from the heating plate12interacts with the treating chemistry in the pad14and on the surface to be cleaned to solubilize and transfer the stain from the surface being cleaned (e.g. carpet fibers) to the pad14. During this period, the pad heater10indicates a cleaning cycle is still in process, for example by illuminating one of the LED indicators54on the control panel18.

At the end of the cleaning cycle100, an indicator on the control panel18can show that the cycle is “complete.” For example, after the final dwell period106, the timer circuit can supply power to one of the LED indicators54on the control panel18that illuminates to alert a user that the cleaning cycle100is complete.

It is noted that the stain release, transfer and removal process may occur during any period or periods of the cleaning cycle100. For example, stain release and transfer may begin during the initial dwell period102, or not until the heating period104. Also during the cleaning cycle100, the weight of the pad heater on the pad can help absorb stain residue from deeper within the surface to be cleaned; in the case of carpet, from deeper within the carpet and the carpet backing.

It is also noted that the exemplary times indicated in parenthesis in combination with the indicated temperature has been shown to maximize cleaning without damaging carpet dyes, which is especially important on aged carpet which is more prone to fading when treated with comparatively higher temperatures for a longer period of time.

The disclosed intervals—the initial 5 minute dwell period, followed by 1 minute of energizing the heat plate, followed by a final 5 minute dwell period—can be adjusted and optimized depending on characteristics of the surface to be cleaned and details of the particular stain. Multiple cleaning cycles may be provided, and the user may be able to select between different cycles based on the stain to be treated and/or the stain treatment pad to be used.

A method of treating a stain on a floor surface using any embodiments of the pad heater10and stain treatment pad14disclosed herein can include the steps shown inFIGS. 9A-9J. The specific sequence of steps discussed is for illustrative purposes only and does not limit the method unless otherwise noted, as it is understood that the steps may proceed in a different logical order, additional or intervening steps may be included, or described steps may be divided into multiple steps, without detracting from the invention.

To treat a stain108, (a) the user opens a package containing a pre-wetted stain treatment pad14, and (b) places the pad14directly on the stain108. The user (c) plugs in the power cord44of the pad heater10, (d) pulls the tether62to retract the guard66and expose the heating plate12, and (e) places the pad heater10on the pad14, with the heating plate12in direct contact with the top of the pad14, while still pulling the tether62taut. With the pad heater10on the pad14, the user (f) releases the tether62and (g) selects a cleaning cycle via the control panel18, which starts a heating operation. The pad heater10carries out the rest of heating operation on the pad14to treat the stain without requiring further action by the user (h). The heating plate12warms the pad14to add heat energy to the chemical reaction between the surface and the treating chemistry of the pad14to promote the stain release, transfer and removal process. After the heating operation is complete, the user can (i) pick up the pad heater10and pad14from the surface. The wet pad14may stick to the bottom of the pad heater10due to surface tension. The user may pull the tether62taut while lifting the pad heater10off the surface to avoid the guard66closing over the used pad14. The pad14can (j) be peeled off the heating plate12and disposed of, or saved for another cleaning cycle.

There are several advantages of the present disclosure arising from the various features of the apparatuses, systems, and methods described herein. For example, the embodiments of the invention described herein provides an unattended and portable heating device that is configured to heat a pre-wetted stain treatment pad to remove tough, set-in stains from carpet and rugs. Using a prior art steam mop which operates at 212° F. (100° C.) or more or a clothing steam iron which operates at 356-428° F. (180-220° C.) would not work as well as the apparatuses, systems, and methods described herein, because the temperatures at which these devices operate are too hot, which can actually release factory dyes from carpet and fade or “bleach” carpet.

Another advantage of the present disclosure is that some embodiments the apparatuses, systems, and methods described herein provides an unattended and portable heating device with a retractable guard feature that automatically shields the user and anything else from the heating plate when the device is lifted away from a surface to be cleaned.

The described system and method has further been found to be especially effective on removing stains containing various synthetic dyes such as FD&C Red #40, Blue #1, and Yellow #6, which are commonly used in foods and beverages stains. These dye-based stains are especially difficult to remove from older, worn carpets because over time, stain resistant coatings such as Scotchgard™ or Teflon™, which are typically applied to carpet fibers after the factory dyeing process, can wear away rendering the carpet fibers vulnerable to receiving other dyes and becoming permanently stained. The absence of a protective coating exposes dye sites on carpet fibers, which are charged areas on the fibers that attract oppositely charged dyes. For example, positively charged dye sites on a carpet fiber can attract negatively charged (anionic) dyes, such as acid dyes. Carpet protector coatings block stains because they are negatively charged resins that function like colorless dyes by occupying the positively charged dye sites on a carpet fiber, and thereby block anionic dyes from attaching to dye sites. When protective coatings wear away, exposed dye sites on the carpet fibers can readily absorb dyes from food, drinks and waste similar to the manner in which carpets are originally dyed. It is very difficult to preferentially remove the unwanted dye while leaving behind the original dye in the fibers.

The system and method disclosed herein is designed to safely clean these difficult stains without damaging or lightening the original dyed color of the carpet fibers. It is within the scope of the invention to treat stains containing various other synthetic and/or natural food dyes in addition to those specifically listed above.

To the extent not already described, the different features and structures of the embodiments may be used in combination with each other as desired, or may be used separately. That one pad heater is illustrated herein as having all of the features shown does not mean that all of these features must be used in combination, but rather is done so here for brevity of description. Thus, the various features of the different embodiments may be mixed and matched in various configurations as desired to form new embodiments, whether or not the new embodiments are expressly described.

While the invention has been specifically described in connection with certain specific embodiments thereof, it is to be understood that this is by way of illustration and not of limitation. Reasonable variation and modification are possible with the scope of the foregoing disclosure and drawings without departing from the spirit of the invention which, is defined in the appended claims. Hence, specific dimensions and other physical characteristics relating to the embodiments disclosed herein are not to be considered as limiting, unless the claims expressly state otherwise.