Cleaning textile floor coverings

Abstract

A device for cleaning textile floor coverings contains a housing having wheels (11a, 11b and 11c) and a rotating body (12) for applying an aqueous cleaning agent having a content of volatile solvent which is active in cleaning, preferably an alcohol-containing cleaning agent, suction nozzles (15a) and a hot gas outlet unit (13), by means of which superheated or diluted steam can be applied to the floor covering moistened with the cleaning agent and at which dirt detached from the floor covering can be retained by means of a stretched textile pad. The intensive cleaning method thus carried out is more efficient in terms of working time, permits substantially faster re-acccessibility and thus usability, and is more environmentally friendly because it conserves more water and thus resources than previous methods.

Description

[0001] Cleaning of textile floor coverings

[0002] The invention relates to a method for cleaning textile floor coverings, an apparatus for carrying out this method, a composition for use in this method and the use of a composition in methods for cleaning textile floor coverings.

[0003] The invention can be used in the field of cleaning textile floor coverings, in particular on heavily used surfaces in buildings into which a lot of dirt is introduced but which have to meet increased cleanliness requirements, such as rooms and public areas in hotels or office buildings.

[0004] From RAL 991 / A3:2013, several methods for basic carpet cleaning are known today, and depending on the degree of soiling, combination methods are also available: shampooing, spray extraction (with and without additional brush use) and a "thermoelectric" method, which contains an enzyme cleaner as a cleaning fluid at a constant temperature and is applied using the conventional "pad method".

[0005] In the shampooing process, a relatively concentrated surfactant solution is applied to the carpet and worked evenly into the carpet material using brushes or similar devices, generating a strong foam. DE19511 193A1 describes a process that uses salts of certain di- or polycarboxylic acids instead of surfactants. After a certain exposure and drying time of at least a few minutes, the foam is vacuumed away along with the absorbed dirt, or the cleaner waits until the foam has dried on the carpet before vacuuming away the solid residue.

[0006] In the spray extraction process, however, the spraying and suctioning of a cleaning fluid containing surfactant, citrate, or phosphate takes place one after the other using the same device. For this purpose, the devices have a row of nozzles at the front in the working direction, which are used to blow a diluted surfactant, citrate, or phosphate solution into the textile material. Behind these nozzles is a wide suction nozzle or a row of suction nozzles, which largely remove the applied fluid from the carpet and transfer it to a waste water tank in the device. A brush device for incorporating the cleaning fluid can be provided between the application nozzles and the suction nozzles. One such device is the "Lavor Sprinter" model from the Italian manufacturer Lavorwash. With it, cleaning fluid is applied from a storage tank to the floor using a brush. The dirt-laden fluid is suctioned out and pumped into a waste water tank.

[0007] The third widely used basic cleaning method for carpets is the so-called "pad method." After a cleaning solution has been applied to the carpet in small quantities, it is distributed and worked into the carpet pile by rotating brushes, over which pieces of textile (pads) are pulled. The dirt dissolved in the cleaning solution is bound to the pads in this process. The machines are usually single-disk brush machines, which can also be used for shampooing without a pad covering. The textile covering is replaced with a fresh covering after a certain amount of dirt has been absorbed. This method is usually used in conjunction with surfactant-containing cleaning agents and is only described as a method for intermediate cleaning, as it does not allow for intensive cleaning. DE102005041598B3 describes a cleaning device whose energy is provided by a fuel cell.The cooled liquid from the fuel cell is sprayed onto a textile cover that is pulled over the surface to be cleaned to assist the cleaning process, particularly with the use of a special "FDT enzyme cleaner." This process is not suitable for mass production.

[0008] All of the cleaning methods described have in common that a greater or lesser portion of the cleaning solution is not removed from the carpet and therefore dries there. With the majority of particularly active surfactants or other cleaners, the surfactant, phosphate, or other cleaning agent residues remaining in the carpet can potentially cause the textile material to stick to the carpet or promote dirt deposits, which can accelerate re-soiling. There is also an individual risk of health reactions (allergies) to residual cleaning agent residues. The devices known for spray extraction consume large quantities of cleaning agent and water (approximately 7-10 liters of water per square meter) for intensive cleaning. The recommended waiting time until the carpet is ready to be walked on again is usually 12-24 hours.During this time, for example, hotel rooms are not available for re-occupancy.

[0009] In a special cleaning process developed by the Belgian company De Wit Royal Manufacturers for historic tapestries and carpet runners, the carpet to be cleaned is placed with its underside on a net. A detergent-based cleaning agent is sprayed onto the top of the carpet to create an aerosol, which is then drawn downward through the carpet by a vacuum applied to the underside of the net. After cleaning, any residue of the detergent-based cleaning agent is rinsed out in the same way by drawing through an aerosol of demineralized water.

[0010] It's also common practice to clean surfaces such as house walls or patio floors with so-called steam cleaners. The steam-saturated gas stream, often containing liquid droplets, is directed directly onto the surface, loosening dirt on the surface and sweeping it away into the steam-water mixture. However, due to its destructive power, this method is only suitable for very insensitive surfaces.

[0011] For cleaning hard floors such as tiles or wood floors, the Vileda Steam Plus is currently available on the market. This device directs steam through a microfiber cover (Vileda steam mop) onto the dry floor. The steam kills bacteria and viruses. The device rests on the floor under its own weight and is pushed across the floor. The manufacturer Vileda offers the option of (according to the manufacturer) "refreshing" dry carpets using steam using a plastic cover that acts as a frame to create gliding properties on textile floor coverings, known as "carpet gliders". The manufacturer primarily associates this with a "pile straightening", i.e. standing up of the carpet pile that has been pressed down through use.Intensive cleaning of dry textile surfaces, such as delicate textile floor coverings, was not seriously considered, as it must be assumed that hot steam damages the dry fibers. This device has no option to actively lower or raise the cleaning unit to the floor. Manufacturers of steam cleaners and steam vacuum cleaners, such as Beam, on the other hand, claim a cleaning effect solely through the use of steam on dry textile surfaces while simultaneously vacuuming away the dirt loosened by "dry steam," again without claiming to provide intensive cleaning. Instead, they primarily emphasize the effect of "refreshing and standing up carpet fibers," but remain silent on the effect of possible damage to the unmoistened carpet fibers caused by the heat of the expressly "hot dry steam."

[0012] To clarify RAL 991 / A3:2013, the "werterhalt.org" working group published a leaflet entitled "Cleaning Procedures for Textile Floor Coverings and Their Work Steps," the eighth edition of which was published in 2023. The working group primarily consists of carpet manufacturers. The leaflet describes all cleaning procedures currently in use, classifying them according to their purpose (e.g., intermediate or intensive cleaning), but without establishing a ranking among them. Accordingly, basic or intensive cleaning encompasses the full-surface cleaning of the textile floor covering, down to the entire depth of the wear layer. However, the procedures listed therein are expressly distinguished from steam cleaners, the use of which is now designated as "not permitted" for carpet cleaning (Chapter 8).This represents a more stringent assessment of the use of steam cleaners, as in earlier editions of the information leaflet, the use of steam cleaners was simply described as "unsuitable" under the same Chapter 8. The Fraunhofer Institute for Applied Polymer Research (IAP) is now also a member of the working group. This tightening of the regulations clearly takes into account the fact that manufacturers of steam cleaners and steam vacuum cleaners do not provide any information about the risks, such as scorching, of using steam, sometimes hot dry steam, for dry carpet fibers. With the present invention, such risks are eliminated, as steam is only used on moistened carpet fibers.

[0013] The object of the present invention was to provide a composition for an improved method for cleaning textile floor coverings, a method using this composition as a cleaning agent and an apparatus for carrying out this method.

[0014] This object is solved by the present invention.

[0015] Figure 1 shows schematically a cleaning device according to the invention in a simple embodiment with a rotating body (12) for applying and distributing a cleaning agent onto the textile floor and a hot gas outlet unit (13) with a textile cover for incorporation and dirt absorption, seen from below.

[0016] Figure 2 shows schematically a cleaning device according to the invention in an embodiment expanded compared to Figure 1 by a separate rotating body (14) for incorporating the cleaning agent, seen from below.

[0017] Figure 3 schematically shows a partially transparent side view of a cleaning device according to the invention shown in Figure 2. The essential components are shown schematically. Figure 4 schematically shows a cleaning device according to the invention in which units of two individual devices according to Figure 2 are connected in series. This design is particularly suitable for continuous cleaning in one direction.

[0018] One object of the invention is a device for cleaning textile floor coverings comprising

[0019] • a unit for applying an aqueous cleaning agent to the textile floor covering (application unit),

[0020] • a unit with a hot gas permeable pad (hot gas outlet unit) that can be moved over the textile floor covering, and

[0021] • a unit for generating steam to pass through the pad onto the textile floor covering (steam generation unit).

[0022] Textile floor coverings are defined according to EN 1307. They are essentially fibrous, flat coverings that are attached to or applied to floors. Due to their fibrous structure, they are softer than hard floors (stone, parquet, laminate, linoleum, tiles, or smooth PVC) and more comfortable to walk on. They are used primarily indoors. They are also rough and have gaps. In contrast to smooth floor coverings, textile floor coverings can absorb larger quantities of dirt without people walking over them noticing. Common textile floor coverings are carpets and rugs. The invention is particularly suitable for cleaning floor coverings with an area of ​​more than 1.5 m². 2According to the invention, textile floor coverings of various types and textures can be cleaned. Carpets made of synthetic fibers are preferred, either with an open pile or with looped fibers. Examples of synthetic carpets are velour carpets. Depending on the type of room in which the floor coverings are installed and the degree of wear, different fiber materials and fiber lengths are used. Based on tests conducted so far, the invention is particularly suitable for synthetic fiber carpets with a pile height of between 1 and 15 mm.

[0023] The device according to the invention is particularly well-suited for the quick yet intensive cleaning of larger areas, such as those found in public buildings. With a single device according to the invention with a working width of 20 cm, a carpet with an area of ​​1 m 2in two minutes. Accordingly, a device with a working width of 1 m can clean an area of ​​5 m 2 cleaned. An entrance area of ​​150 m 2 A hotel area could be thoroughly cleaned in about 60 minutes.

[0024] The cleaning of textile floor coverings serves to remove solid or liquid dirt that has accumulated over time in the floor covering, particularly in its interstices. Common dirt contains, for example, particles such as sand or dust, or liquids or dried liquids such as drink and food residues, including grease. The dirt can be loose in the floor covering or bound to the textile fibers. Cleaning takes place on and from the upper side of the textile floor covering, the pile side, by moving the device according to the invention over it. Therefore, the floor coverings can remain in their original place on the floor during cleaning. An aqueous cleaning agent is a liquid that contains water to which other substances are added, dissolved, emulsified, or suspended. It is preferably a liquid solution.The cleaning agent is used to remove dirt from the textile floor covering. To do this, the floor covering is moistened with the cleaning agent and worked into the floor covering for the most intensive cleaning possible. During a contact time, any dirt that is soluble in the cleaning fluid or physically or adsorptively bound is released from the floor covering and can then be removed.

[0025] Aqueous cleaning agents are described in the prior art. These essentially contain surfactants, acid salts such as phosphates and citrates, and / or enzymes. However, these have the disadvantage that they are non-volatile and remain in the floor covering in non-negligible quantities, even after the majority of the contaminated cleaning agent has been removed. In a particular aspect of the invention, the aqueous cleaning agent is a cleaning agent without non-volatile components or with a non-volatile content of less than 1% by weight. These non-volatile components can, for example, serve purposes unrelated to cleaning, such as odorization. Substances with an evaporation number (measured according to DIN 53170) of more than 500 are referred to as non-volatile components.The cleaning agents according to the invention preferably contain a cleaning-active content of volatile solvents, preferably volatile organic solvents. Volatile solvents are solvents with an evaporation number (measured according to DIN 53170) of less than 80, preferably less than 50, particularly preferably less than 33. Such volatile solvents are, in particular, water-soluble C1-C5 alcohols. The cleaning-active content of volatile solvent is, in particular, up to 50 wt.%. Particularly suitable cleaning agents are described in more detail below in connection with a process according to the invention.

[0026] In addition to the aforementioned units, application unit, steam generation unit and hot gas outlet unit, the device according to the invention comprises further units that are required for carrying out the cleaning of the textile floor covering and can have additional units that support the cleaning or enable or facilitate the use of the device. Such units are described in more detail below. A unit is understood to be a structural component of a device with a specific function. The device according to the invention preferably has a housing in which these units are accommodated and an operating part, for example a handle, with which the units can be activated and by which the device can be moved over the floor covering. The units are preferably movably mounted in the housing; in particular, one or more units in the housing can be moved vertically relative to others in order to be moved specifically towards or away from the floor covering, i.e.To be lowered onto or raised from the floor covering. The device also has rollers or wheels on which the device, with its units in the raised or lowered state, can be moved horizontally across and on the floor covering.

[0027] The purpose of the unit for dispensing the aqueous cleaning agent is to moisten the textile floor covering before treatment. Even moistening is desired. Suitable dispensing units therefore contain one or more nozzles that can be directed onto the floor covering and with which the cleaning agent is sprayed as evenly as possible. Such units are known from the prior art. The dispensing unit is positioned in the device according to the invention such that it can be guided over the floor covering to be cleaned. To ensure that the applied cleaning agent actually reaches the floor covering, the dispensing unit should be spatially separated from units for suction, for example by aprons extending down to the floor covering and surrounding the dispensing unit or the suction unit.Alternatively or additionally, the application unit in the form of one or more nozzles can be positioned outside the device housing, for example in front of or next to the housing.

[0028] The device according to the invention advantageously comprises a storage container for the cleaning agent. Its size and capacity are determined by the duration of operation of the device without refilling the cleaning agent and the amount consumed. If multiple cleaning agents are to be used, multiple storage containers can also be provided. If the cleaning agent consists of several components, these can also be stored in separate storage containers and mixed together shortly before use. This allows for the adjustment of an adjusted mixing ratio of the components. If the cleaning agent or its components are temperature-sensitive, or at high ambient temperatures, the storage container can be thermally insulated and / or cooled, particularly compared to units with elevated temperatures.

[0029] The application unit optionally also includes a wetting unit for mechanically distributing the cleaning agent throughout the floor covering. One or more coarser rotating or vibrating bodies, adapted to the nature of the floor covering, are suitable for this purpose. These bodies are designed to wet the soiled fibers with the cleaning agent deeply across the entire covered area and to loosen existing bonds, preferably mechanically, to conserve resources. These bodies can be rotatable about an axis parallel or perpendicular to the floor covering plane. Rotating bodies in the form of brushes are known from the prior art. Brush rollers with plastic bristles, such as those used in the "Lavor Sprinter" device from Lavorwash, are suitable for incorporation.Devices with brushes are less suitable for floor coverings with fibers that tend to produce more lint, such as new wool, as they clog up more quickly and the mechanical cleaning effect diminishes more quickly. In one aspect of the invention, the application unit is mounted in a height-adjustable housing so that it can be lifted off the floor covering, does not touch the floor covering, and thus offers no frictional resistance during other processing steps when the device is moved over the floor covering. Details of a suitable vertical movement unit are described below.

[0030] The device according to the invention optionally further comprises a working unit with one or more softer or bristle-free rotating or vibrating bodies for intensively processing the wetted surface of the floor covering and loosening the dirt. A roller covered with a microfiber cover featuring outwardly projecting textile threads is suitable for this purpose. In a simple form, the cover is made of the material of a car wash mitt. Removing the dirt from the fibers does not necessarily lead to the removal of the dirt, since the materials of the brushes or surfaces absorb practically no dirt when wet. The degree of moistening and the working time can vary depending on the type of carpet and the associated risk of lint loss during mechanical processing.In the best case, more intensive processing can compensate for lower moisture penetration, leading to improved resource conservation while allowing the floor to be accessed sooner. In one aspect of the invention, the incorporation unit is height-adjustable so that when not in use, it can be lifted off the floor covering, thus avoiding contact with the floor covering and creating no frictional resistance when the device is moved across the floor covering during other processing steps.

[0031] The discharge unit and the incorporation unit are always separate from each other. The incorporation unit and the hot gas outlet unit can be separate from each other or combined in a simple design. It is advantageous to house the units in a part of the device housing that is structurally separate from the other units in the housing, but connected to them.

[0032] In a simple embodiment, the cleaning agent is sprayed onto a rotating body (brush roller) and applied by this into the fibers of the floor covering, then distributed and worked into the floor by the combined incorporation and hot gas outlet unit (see below) through vibration, whereby the dirt is loosened.

[0033] If both an application unit and an incorporation unit are present, they can be activated together or separately using a control system, for example, turned on and off, or adjusted in height. In the case of two rotating bodies, these can be operated at different rotation speeds or directions to achieve different processing intensities.

[0034] In the device aspect of the invention, the device according to the invention has a gas outlet unit configuration, namely a hot gas outlet unit. Its essential component is a unit with a hot gas-permeable textile, preferably in the form of a so-called pad, that can be moved over the textile floor covering. This hot gas outlet unit has two functions: firstly, it applies hot gas through the pad onto and into the moistened and prepared floor covering, and secondly, it absorbs dirt onto the pad. Pads for absorbing dirt are known from the prior art. Secondly, the pad according to the invention is sufficiently permeable to hot gas. For this purpose, the pad has a plurality of pores through which the hot gas can penetrate the pad. It is preferably a textile fabric with fringes on the side of the pad facing the textile floor covering.Suitable textiles (including those from the state of the art) are commercially available, e.g. for the "steam mop" from the manufacturer Vileda, or can be determined by a specialist through simple tests. It is important that the amount of hot gas penetrating the pad is sufficient to ensure adequate steaming of the part of the floor covering beneath the pad. The variables that determine the permeability of the pad are, in particular, the pore size of the pad, the applied pressure, and the mechanical strength of the pad. Suitable hot gases for the purposes of the invention include superheated steam or mixtures of steam with other gases, for example air, hereinafter referred to as diluted steam or unsaturated steam.

[0035] The hot gas flow through the pad in the tests conducted at a pressure between 7.7 bar and 8 bar was measured at 500 g / min to 600 g / min for maximum bursts, with a continuous hot gas output of 155 g / min to 180 g / min between the maximum bursts. The hot gas outlet unit, both in its combined version with the incorporation unit and independently, is height-adjustable within the housing so that it only comes into contact with the carpet when activated via the control unit for hot gas discharge and absorption of the loosened dirt, or previously for incorporation via vibration in the combined version.

[0036] Textiles with a large surface area for absorbing dirt are particularly suitable as pads. State-of-the-art materials for steam mops are also suitable for this purpose. Suitable pads are generally made of microfiber cloths with microfiber textile threads. These textile threads are flexible and differ from the plastic bristles of brush rollers in that they do not elastically return to their original shape after deformation. The length of these textile threads can be between 0.2 and 2 cm. They are typically between 1 and 5 mm thick. Commercially available mops have textile threads that are approximately 1 cm long. The density of the textile threads on the microfiber backing is approximately between 5 and 20 textile threads per cm. 2. The pad is attached close to the floor covering to be cleaned, preferably on the underside of the hot gas outlet unit and the device, so that the textile threads can point towards the textile floor covering. It is attached in such a way that the textile threads can be brought into contact with the floor covering. In a first embodiment, the pad is stretched onto a brush roller, the same as the one used to work in the cleaning agent. The movement of the brush roller in a lowered position on the floor covering, e.g. by rotating, simultaneously enables a mechanical loosening of the floor covering while the hot gas is applied. Preferably, however, it is attached to the device in such a way that the textile threads of the pad lie flat on the floor covering when the unit is operating in the lowered position. The pad can be attached in different ways to the underside of the unit, towards the floor covering.The hot gas outlet unit can be equipped with a motor to generate vibration and a vertical movement unit that allows the pad to be actively or passively lowered into the housing onto the floor covering. To ensure a sufficient service life, the pad should be heat-resistant within the temperature range of the hot gas passing through it for the duration of its use.

[0037] In a preferred embodiment of the hot gas outlet unit, the pad is mounted on a body that rests on the surface of the floor covering to be steamed during the initial stage of the steaming process. The body is preferably mounted for movement and is so heavy that, when exposed to hot gas, it lifts itself like a steam cushion due to the pressure exerted by the pad on the floor covering, allowing the hot gas outlet unit to be moved easily, as if weightless, across the textile floor covering by pushing and pulling. The body can also be a horizontally and vertically movable vibrating body.

[0038] In one aspect of the invention, the hot gas outlet unit is height adjustable so that it can be lifted off the floor covering and no longer touches the floor covering and thus does not provide any frictional resistance when the device is moved over the floor covering during other processing steps.

[0039] The pads are attached to the unit in such a way that they can be replaced on request or when their dirt absorption capacity is exhausted. This can be achieved using known measures, for example by elastic tensioning or by means of springs or clamps. In the simple version with a combined incorporation and hot gas outlet unit, unconditional adhesion of the pad to the unit must be guaranteed to enable vibration. In the other versions with separate units for hot gas outlet and incorporation, the pad that only serves to absorb dirt and is not used for vibration during incorporation can alternatively be attached in forms that do not have to meet the increased adhesion requirements during vibration. For example, it can also be wound on a supply roll from which it is moved further on the body, for example via rollers, so that fresh textile can be provided as needed.For example, the pad can be contained in a cassette in which the pad can be advanced automatically or manually to provide a fresh, uncontaminated portion of the pad, and which can be easily replaced when the entire pad's dirt absorption capacity is exhausted. Contactless pad advancement has the advantage that the cleaning process does not have to be interrupted to cool the pad, which has become hot from the previous steaming.

[0040] Microfiber pads, like those found on mops, are particularly suitable. These are made of very fine textile threads and can easily absorb dirt particles.

[0041] The hot gas outlet unit can have additional functions. For example, it can also be used to work the cleaning fluid into the pad if it has suitable components, such as rotating or vibrating elements (see above under "Working Unit"). These are then preferably located on the side of the textile / pad facing away from the floor covering and towards the steam chamber. To work the cleaning fluid into the pad, the rotating or vibrating elements can be set in motion before or during the hot gas exposure. This also moves the textile, ensuring that the cleaning agent is worked into the floor covering and that dirt is loosened from the floor covering. If the movement occurs while the hot gas is applied and the pad is in contact with the floor covering, the hot gas can be better distributed throughout the floor covering, absorbing and removing dirt and cleaning agent.The movement of the pad and the exposure to hot gas can also occur alternately and several times in succession.

[0042] Another essential component of the device according to the invention is a unit for generating steam (steam generator or steam generation unit). The generated steam serves either directly as hot gas or to generate hot gas. Steam generators are known for other purposes, such as steam cleaning of surfaces. Their output must be such that the generated steam is sufficient to apply hot gas to the pad and dry the floor covering as intended. Therefore, the required performance of the steam generation unit depends on the surface of the pad, its permeability to hot gas, the desired speed of movement over the floor covering, and the desired degree of drying of the floor covering. This can be determined using simple manual tests. For a pad area of ​​300 cm2 and a gas flow of around 200 g / min, an electric steam generator with an output of 2500 W has proven sufficient. This makes it possible to generate pressures of between 5 and 10 bar. Such steam generators are known, for example, from steam irons or steam cleaners. Steam generation preferably depends on the cleaning status and the movement of the device. Operators can start steam generation manually or it can be controlled independently by a microcomputer. For energy-saving use, the steam generation unit can be thermally insulated. The steam generation unit is preferably housed in the housing of the device and is electrically operated. It is connected via a steam pressure line and a controlled valve to the space in the pad facing away from the floor covering, so that when the valve is opened, the hot gas generated can escape through the pad onto the floor covering.

[0043] The device according to the invention preferably has a storage tank for water, which is heated in the steam generation unit and converted into steam. The size of the storage tank depends on the desired operating time of the device without refilling. The storage tank is connected to the steam generation unit via a controlled metering pump.

[0044] The steam generated in the steam generation unit can be made available to the hot gas outlet unit directly as superheated steam or, after mixing with other gases, preferably air, as diluted steam. When the steam is used directly, the device according to the invention preferably has a steam generation unit suitable for generating superheated steam. This must be capable of generating steam at a pressure of between 5 and 10 bar, for example 7.7 bar. The valve for opening the steam pressure line from the steam generator to the space behind the pad is controlled such that the superheated steam can escape from the steam generator in bursts and explosively and be applied to the floor covering through the pad. The control ensures that the valve is closed again as soon as the excess pressure has essentially been reduced.The valve opening time is therefore advantageously between 0.2 and 2 seconds, preferably between 0.5 and 1 second. The valve is kept closed until sufficient overpressure has built up again. The closing time therefore depends on the steam generator's steam generation capacity and is advantageously between 0.5 and 10, preferably between 1 and 5 seconds. As soon as sufficient overpressure is present, the next steam burst can be applied. These steps can be repeated until the desired cleaning effect is achieved. The control can also be linked to the device's movement so that each steam burst detects the new floor covering to be treated.

[0045] In the event that the hot gas is not saturated with water vapor (unsaturated water vapor), gas, preferably air, is mixed with the water vapor generated in the steam generation unit before it is applied to the floor covering. For this purpose, the device preferably has a mixing valve with which air is mixed with the water vapor generated in the steam generator. There are several options for achieving the required temperature in the unsaturated hot gas. Either the supplied air is heated so that the desired final temperature is achieved through mixing with the generated steam, or the hot gas is subsequently brought to the temperature, for example using an electrically controlled heater. The latter option allows for more precise adjustment of the hot gas temperature, which is important, for example, for sensitive floor coverings that cannot tolerate gas at temperatures of 100°C.In the embodiment of the invention with diluted steam as hot gas, the control is preferably set so that a continuous flow of hot gas is provided.

[0046] Mixed configurations are possible between the embodiment with superheated steam and the embodiment with unsaturated steam as hot gas, for example, with unsaturated, superheated steam as hot gas, or by controlling both configurations sequentially. Furthermore, it is possible to implement both configurations with a continuous or pulsed hot gas flow.

[0047] The hot gas is fed into the space behind the pad, from where it is conveyed through the pad. The hot gas is preferably under pressure, which is generated by the steam generation unit. The drying speed of the floor covering can be adjusted by the saturation level, pressure, impact frequency, quantity and temperature of the hot gas. The lower the saturation level when the hot gas is applied, the more liquid, e.g. water, can pass from the floor covering into the gas and be carried away when exposed to the gas, and the faster the drying process. The greater the pressure, the more dirt and cleaning fluid the hot gas stream can absorb from the floor covering. This in turn has a positive effect on the possible processing speed during cleaning and the suitability of the floor covering for further use. By increasing the gas temperature, the drying process can also be accelerated.

[0048] The device according to the invention can also optionally include a dry vacuum unit, which can be used before the cleaning agent has been applied. This allows for pre-cleaning of floor coverings that are heavily soiled with dry and mechanically loose dirt, thus saving energy and cleaning agent. Suitable units are known from the prior art for so-called vacuum cleaners.

[0049] The device according to the invention further advantageously, or also for reasons of occupational safety, comprises an extraction unit with which hot gas and cleaning fluid can be extracted along with the dirt removed from the floor covering. This is particularly preferred for cleaning agents containing alcohol, when the alcohols should not be released into the environment. This unit is preferably located near the hot gas outlet unit and is structurally separated from the unit for dispensing the cleaning agent, for example by aprons or a control system, so that when the device moves over the floor covering, primarily the dirt-laden hot gas is extracted. For this purpose, extraction nozzles are preferably attached to the side of the device or on the side facing away from the dispensing unit.

[0050] For cleaning floor coverings requiring care, the device according to the invention can optionally further include a unit for applying care or impregnating substances. This can be done, for example, by applying suitable compositions to the floor covering. When using alcohol-based cleaning agents, the use of a lanolin-containing care product to replace the wool grease removed during cleaning has proven advantageous.

[0051] In a particularly environmentally friendly embodiment, the device according to the invention further comprises a condensing unit for the extracted hot gas with a collecting container for the condensate. The hot gas is cooled therein in a known manner. The condensate can then be properly disposed of or reused. Optionally, the condensing unit can also contain means for the prior removal of the entrained dirt, for example, a filter or a centrifuge. The purpose of the condensing unit is to prevent the environment from being contaminated with the ingredients of the cleaning agent and the dirt contained therein, which has been removed from the floor covering, as well as the introduced water vapor. In this embodiment, the device can also be operated in public areas without any noticeable environmental impact.

[0052] The release of alcohol from the floor covering into the environment can be further reduced by cooling the storage container for the alcohol and / or the alcohol-based cleaning agent. This reduces the vapor pressure of the alcohol from the moment the cleaning agent is applied to the moment the hot gas is applied. The greater the cooling, the more the vapor pressure is reduced. Cooling to a temperature between 0°C and 15°C, preferably between 2°C and 5°C, is sufficient for this purpose. The device according to the invention can therefore have a cooling unit for the cleaning agent or its components.

[0053] The device according to the invention can advantageously be operated electrically. Electric motors can be used to operate the included units, but also to propel the device along the floor covering. The housing of the device is conveniently mounted on wheels or rollers, allowing it to be easily moved horizontally across the floor covering.

[0054] The device according to the invention is moved over the floor covering to clean it, so that the units are moved together over the floor covering, and cleaning takes place exclusively from the pile side of the textile floor covering. The amount of cleaning agent applied can thus be used to adjust the depth of penetration of the floor covering. Preferably, the application unit, if desired, the wetting unit and the incorporation unit, followed by the hot gas outlet unit and, if desired, the suction unit, are moved over the part of the floor covering to be treated. If cleaning is not yet complete, the device can be moved over the floor covering again. In the simplest case, the process is repeated in the same order.It is also possible to return the machine over the previously cleaned floor covering without activating the units, and then pass over the previously cleaned area again in the previous sequence with the units activated. It is also possible to deactivate the application unit during the second pass and only activate the hot gas discharge unit and, if desired, the other units. This allows for particularly thorough removal of dirt and residual cleaning agent.

[0055] The speed of the movement is adapted to the type of floor covering, the desired degree of cleaning, the amount of cleaning agent to be used per unit area and the intensity of the processing.

[0056] For smaller areas, the device can have the shape of a classic handheld vacuum cleaner (e.g. Vorwerk or Hoover), for medium-sized areas the shape and size of a standard floor vacuum cleaner or floor cleaner with a handle, and for larger areas devices with a seat for the operator are possible.

[0057] The sequence of the individual work steps of the method according to the invention is advantageously regulated by a control unit. The control can be manual, semi-automatic, or automatic. Such control systems are known in principle and can be programmed accordingly based on the described work steps. Preferably, the control is designed so that, for a specific partial area of ​​the floor covering, the step of applying the cleaning agent is initialized before the steaming step. To control the hot gas outlet through the pad, both the steam generation unit and the valve for discharging the hot gas into the hot gas outlet unit must be initialized. Temperature and pressure measuring devices, which transmit the measured values ​​to the control unit, are advantageous for this purpose.

[0058] Furthermore, it is advantageous if the device has a display unit on which the parameters essential for the operation of the device according to the invention can be displayed. These include the operational readiness, the steam pressure, the fill level of the storage containers, the fill level of the waste containers, and the operating time of the pad.

[0059] In the tested versions, which generate particularly little resistance when moving across the floor covering, only the currently activated unit is lowered onto the floor covering. This lowering occurs particularly for the units that are intended to come into contact with the floor covering. These are the incorporation unit and the hot gas outlet unit. The raising and lowering can occur dependently or independently of the device's direction of movement. The raising and lowering of the units is accomplished by a vertical movement unit.

[0060] The invention therefore also relates to an apparatus for cleaning a textile floor covering, comprising a. one or more units selected from i. a unit for applying an aqueous cleaning agent to the textile floor covering (application unit), ii. a unit for incorporating an aqueous cleaning agent into the textile floor covering (incorporation unit), b. a hot gas outlet unit with a hot gas-permeable pad that can be moved over the textile floor covering, and c. a unit for raising and lowering the units from a. and b. onto the floor covering (vertical movement unit).

[0061] The operation of the units is facilitated by the activation of appropriate actuators. Control can be carried out via the control unit, which is conveniently operated via buttons or a control panel.

[0062] The size of the device according to the invention depends on the function and number of usable units, as well as the size of the area to be cleaned. For example, a simple handheld vacuum cleaner-like device for cleaning smaller hotel rooms can have a width of 20 to 50 cm and a length of 40 to 60 cm; a simple floor-mounted device for cleaning larger rooms can have a width of 40 to 60 cm and a length of 50 to 80 cm; while large or ride-on devices for cleaning large areas can have a width of 50 to 100 cm and a length of 60 to 150 cm.

[0063] In the following, suitable devices according to the invention for cleaning a carpet are explained by way of example with reference to the drawings, which also include optional units.

[0064] The devices described below, in the Mini, Midi and Maxi variants, have the following in common (reference numerals with reference to FIGS. 1-4): A box-shaped device standing on wheels / castors (11), in each of the three different variants, has at least one flat hot gas outlet unit (13) for unsaturated steam that can be lowered and retracted vertically and is supplied by a steam generation unit (3) via a hose line. Via this, a constant gas flow of approximately 155 g / min with a pulse-like, adjustable maximum burst of approximately 500 g / min of steam at a pressure of around 7.7 bar is discharged downwards onto the carpet by means of a steam outlet valve (4) at the required frequency. The textile is stretched across the outlet surface to collect and absorb the previously loosened dirt.This textile is replaced as part of a large textile roll by means of a lockable roller technology, as needed by further rotating the textile roll after dirt saturation with an unused part of the textile roll.

[0065] The emitted hot gas preferably does not leave the box-shaped unit, but is drawn into the hollowed-out base (15) via an extraction device (18) immediately after penetrating the textile and contacting the damp carpet through outlets (15a) in the base of the device. It is condensed, and the condensate is fed into the cleaning fluid tank (1) for reuse. An apron (15b) around the base of the device additionally provides a seal between the box-shaped unit and the carpet.

[0066] Common to all three device variants described below is the provision of two liquid tanks equipped with hoses and pumps. One of these contains the aqueous-alcoholic solution (1), the other (2) pure water for steam generation. Hoses carry the aqueous-alcoholic solution to several outlet nozzles (6 and 7), which exit one side of the wall of the box-shaped unit in the working direction, but are simultaneously directed into the interior of the box-shaped unit, where they moisten a rotating body (12) designed to deeply moisten the carpet.

[0067] The second tank (2), intended for steam generation, is connected to the steam generation unit (3), which is connected to a steam outlet valve (4). Furthermore, all device variants feature a pump for each of the two tanks and their respective hose systems for transporting the liquids to the required location.

[0068] Also common to all variants is a control unit (17) which controls and activates all other units, as well as at least one electric motor (9) which drives the rotating or vibrating bodies for applying (12) and incorporating (14) the cleaning fluid into the carpet.

[0069] Also common to all variants are actuators (8) that are connected to the control unit and enable the individual raising and lowering of the rotating or vibrating bodies as well as the hot gas outlet unit.

[0070] In all variants, the box-shaped unit features an additional, albeit smaller, third fluid storage tank (5) including a pump. A dedicated hose system leads from this to a third outlet nozzle (10), which, depending on the device variant, leads to the rotary or vibrating incorporation elements (14). The purpose of this third tank (5) is to store and dispense agents for regreasing or impregnating the carpet after the cleaning steps have been completed. These agents must be worked into the carpet before it is completely dry. The method of incorporation follows that for the carpet cleaning agent.

[0071] Mini variant (FIG. 1)

[0072] In addition to a rotating body for liquid application and distribution, this variant does not have its own rotating body for incorporating the cleaning agent (14) and, due to its compact design and improved maneuverability, requires only three wheels / rollers (11), two wheels at the rear and one roller at the front in the working direction. The incorporation task is performed here by vibration of the suitable and stretched textile on the hot gas outlet unit (13), which forms a fixed unit with it. For the various work steps, which begin with the application of the cleaning agent, the rotating body (12) and the hot gas outlet unit (13) are each lowered onto the carpet or lifted off it. For this purpose, both units are connected by suspension with controllable actuators (8).

[0073] Fundamentally, there is a functional separation between the brush application and cleaning agent application on the one hand, and the dirt pickup via the hot gas application and the textile on the other. This separation is implemented differently in the various device variants. In the Mini variant, the working direction determines whether the brush application with manually controlled (optionally via automatic programming) application of the cleaning agent or the use of hot gas for dirt removal.

[0074] In the first step, the rotating body (12) is lowered onto the carpet and simultaneously wetted with cleaning fluid, while the hot gas outlet unit (13) with the textile cover is raised so that there is no longer any contact with the carpet. In this device variant, the control of the actuators (8) changes with the working direction: if the Mini variant, which is comparable in size to a handheld vacuum cleaner, is pushed forward, the rotating body (12) is lowered onto the carpet. It is recommended that rotation begins with the initial lowering, but only ends when the cleaning agent application and distribution phase with brush use is completed. It is harmless if the hot gas application phase begins by pulling back in the working direction during this phase, as long as the brush is raised during the hot gas application.Constantly switching between turning the rotation on and off is not necessary. When the brush is lowered and before use, both nozzles (6 and 7) ensure sufficient moistening of the carpet when manually controlled. Pulling back the Mini version triggers a command to change the working unit to the two actuators (8), causing the rotating body (12) to rise and the hot gas outlet unit (13) to lower onto the carpet. Depending on the work progress, the dual function of the hot gas outlet unit (13) allows the system to switch between the two functions of vibration for incorporation and steaming for dirt collection using an additional manual control.

[0075] Variant Midi (FIG. 2 and FIG. 3)

[0076] The box-shaped unit has the hot gas outlet unit (13) with the stretched textile centered and a rotating body next to each of them (in front and behind, in the working direction). All three working units are connected to actuators (8) that enable the units to be lowered and raised individually. In this variant, too, the activation of the respective working unit alternates with the working direction as described under the Mini variant. The independent functionality of the two rotating bodies for dispensing and distributing the cleaning agent on the one hand and for incorporating the agent on the other hand must be guaranteed. This can only be initiated individually by manual commands from the user depending on the work situation. The user must be able to choose between further moistening of the carpet and localized, more thorough removal of dirt by incorporation.The rotating body that is not required at any given time must therefore be able to be raised individually in phases by the user's command.

[0077] As described in the Mini version, the Midi version also features a fundamental functional separation between the application / distribution of the cleaning agent and the use of hot gas. In addition to the working direction, changing the application should also be possible via manual command, in order to accommodate individual work situations with increased needs for humidification or incorporation by changing the working direction, without necessarily requiring the use of hot gas.

[0078] The hot gas is applied after completion of the first two work steps with the respective rotating bodies in such a way that both rotating bodies are raised beforehand and only the hot gas outlet unit (13) is used. The Midi variant is characterized by the fact that a larger area is wetted in the first work step, onto which an equally dimensioned incorporation takes place, with the working direction being determined by a guide bar (16) that can be pivoted by approximately 140 degrees. In this way, the working direction can be determined with two options: If desired, pivoting the guide bar triggers the command to change between the two basic functions, rotation or hot gas application, thus avoiding the need to pull the entire device, which will have a considerable weight in the Midi variant, towards you in the opposite direction of the previous working direction to collect dirt.This also avoids the need to rotate the Midi variant 180 degrees around its own axis in the desired direction if, depending on the particular work situation, it is desired to work in longer paths and there is insufficient space to turn the entire device (e.g. hotel corridors). In this case, pivoting the guide bar also gives a command to change the direction of rotation of the brushes, again avoiding the need to work by pulling the device. Fig. 3 also shows a cassette in which the pad is moved from a roll for fresh pad (19a) to a roll for dirty pad (19b).

[0079] Variant Maxi (FIG. 4)

[0080] The box-shaped unit has two working units, each consisting of a hot gas outlet unit (13), an output unit (12) with a rotating body, and an incorporation unit (14) with another rotating body, one behind the other. The sequence in the working direction is determined by the work steps already described: output unit (12), incorporation unit (14), textile-covered hot gas outlet unit (13). In the Maxi variant, as a large device, work is carried out in both directions by pushing, similar to the Midi variant, with a function change device (manual or with automatic program) to avoid turning the device. In ride-on devices, the function change device is omitted, and work is carried out in only one direction and controlled manually. The activation of the respective working unit for the scheduled work step takes place exclusively according to the programmed device software and depending on the work path covered.

[0081] Another object of the invention is a method for cleaning a textile floor covering comprising

[0082] • Applying an aqueous cleaning agent to the textile floor covering, and

[0083] • Moving a gas-permeable pad over the textile floor covering moistened with the cleaning agent, characterized in that the aqueous cleaning agent has a cleaning-active content of one or more volatile solvents.

[0084] Volatile solvents are components of the aqueous cleaning agent that can be expelled from the floor covering with the help of hot gas. A volatile solvent is therefore one with an evaporation number (measured according to DIN 53170) of less than 80, preferably less than 50, in particular less than 33. For practical reasons, the evaporation number should be greater than 1. Such volatile solvents are, in particular, organic solvents. The volatile solvents are advantageously liquids that are soluble in water. The cleaning-active content of volatile solvent or the cleaning-active content of a mixture of volatile solvents is preferably up to 50 wt.%. This content is also limited by the fact that the volatile solvent or the mixture should be soluble in water at this content in order to achieve even application.A cleaning-active content is defined as the concentration at which dirt or dirt particles can be released from the textile floor covering, especially organic compounds such as fats, in the cleaning agent due to the solvent content.

[0085] In the following, percentages for components are understood to mean percentages by weight (wt%), unless otherwise stated.

[0086] The cleaning agent used in the process according to the invention is characterized as a liquid in that it contains mainly volatile components and at most small amounts of components that remain in the floor covering after the majority of the contaminated cleaning agent has been removed. The cleaning agent may contain non-volatile additives in small amounts for purposes unrelated to cleaning, for example for odorization, or if it is desired that these can or should remain in the floor covering after cleaning. Examples of these are fragrances, such as perfumes, or textile care products, such as refatting agents or other fiber protectants. The content of the non-volatile additives is usually less than 1%, preferably approximately zero%. Substances with an evaporation number (measured according to DIN 53170) of more than 500 are referred to as non-volatile additives.In this aspect of the invention, the content of non-volatile additives in the aqueous cleaning agent is less than 1 wt%, preferably approximately zero wt%.

[0087] The cleaning agent preferably contains no toxic components in its formulation. Water is preferred as the main ingredient of the cleaning agent because it can dissolve many common contaminants, such as salts. Cleaning agents that can dissolve and absorb liquids or dried-on liquids, such as dried-on beverage residue, have also proven advantageous.

[0088] These requirements are particularly met by cleaning agents that contain one or more organic alcohols with a chain length of between 1 and 5 carbon atoms as volatile organic solvents. These are referred to below as C1-C5 alcohols. C2-C3 alcohols, such as ethanol, n-propanol, and isopropanol, are particularly suitable. Due to their largely non-toxic nature and high volatility, especially in combination with water, their solubility in water, and their dissolving power for organic substances, isopropanol and ethanol are excellent volatile solvents. The cleaning agent may also contain other volatile, non-cleaning components.

[0089] The C1-C5 alcohol content can range from 5 to 45% and depends on both the type of soiling and the purpose of the cleaning (intensive or intermediate cleaning). The C1-C5 alcohol content should preferably not exceed 39% by weight. For common soiling, a content of between 15 and 39% has proven suitable. The alcohol content can also be selected depending on the degree of soiling. For example, in a variant of the process for mere intermediate or maintenance cleaning, the alcohol content can be lower, for example, 5-15%, for surfaces where water-soluble soils predominate (such as hotel entrance halls in winter due to road salt buildup). Surfaces that are more likely to be soiled with food or beverage residues (such as in restaurants) require a higher alcohol content, for example, 25-39%, and should be treated with intensive cleaning.For particularly good intensive cleaning, the alcohol content is usually about one third of the liquid.

[0090] In a tested application involving the cleaning of carpets in a household, a cleaning fluid with an alcohol content of 33% isopropanol or 33% ethanol in water proved highly effective. Ethanol is preferred due to its ready availability and largely biodegradable nature.

[0091] The release of alcohol vapors is already minimized by design measures and functions, not least through cooling and thus delaying evaporation. The use of ethanol, in particular, contributes significantly to minimizing odor nuisance, which can be more noticeable for isopropanol. Danger points of potential evaporation can be reliably avoided by using the process as intended.

[0092] The use of the cleaning agent according to the invention in processes for cleaning textile floor coverings is also made possible by the fact that, after a short exposure time, it can be quickly expelled from the textile floor covering moistened with the cleaning agent by hot gas. This is not possible with conventional cleaning agents. The (non-volatile) surfactants and enzymes usually used in carpet cleaning agents can be completely dispensed with. This has the major advantage that they do not remain in the carpet and can stick to it or do not have to be washed out of the carpet again. This makes it possible to work with smaller quantities of liquid according to the invention. Surfactants and enzymes are also more expensive than low-chain alcohols, which can be produced industrially on a large scale and inexpensively.

[0093] The method according to the invention comprises essential steps for cleaning success, which, however, can be supplemented by further steps depending on the floor covering to be cleaned.

[0094] In a key step, the cleaning agent is applied to the textile floor covering to be cleaned. This serves to moisten the floor covering so that the cleaning agent can absorb the dirt to be removed. In this respect, the method according to the invention does not differ significantly from known methods, except that a different cleaning agent is applied. The amount of cleaning agent applied can be varied depending on the type of floor covering (high-pile / low-pile, dense / loose) or the desired cleaning intensity (deep-penetrating / superficial, intensive / deep cleaning, heavily soiled, lightly soiled).By using the cleaning agent according to the invention, the amount of cleaning agent required for the same floor covering can generally be reduced compared to the known methods, in preliminary tests by up to 90%, in individual cases, depending on the degree of soiling, the nature of the carpet and the use of the method for intermediate or intensive cleaning, even up to 95%.

[0095] Application can be carried out in a known manner, for example by spraying the cleaning agent onto the floor covering from one or more nozzles arranged so that the entire working width of the floor covering is moistened as far as possible. The cleaning agent can then penetrate the floor covering through the capillarity of the pile. The amount applied can be determined by the operator or linked by the control system to the type of floor covering and / or the speed of the forward movement. Another suitable and known method of application is processing the floor covering using moistened rotating bodies, via which the cleaning fluid is introduced into the floor covering. In the case of brush rollers, the bristles of the rotating body cause the textile fibers of the floor covering to untangle and straighten as the brush rotates, enabling the cleaning agent to penetrate better between the textile fibers of the floor covering.In this case, the rotating body can be lowered onto the floor covering. These options can also be combined.

[0096] The other essential step is the movement of a gas-permeable pad over the textile floor covering, which is moistened with the cleaning agent and, if desired, into which the cleaning agent is incorporated. For this purpose, the pad can be lowered toward the floor covering.

[0097] This step has at least two functions: On the one hand, the pad can apply gas to the moistened floor covering, and on the other hand, dirt from the floor covering can be absorbed by the pad.

[0098] The first function is achieved by introducing gas, as described above for the device according to the invention, into the space behind the pad and guiding it through the openings / pores of the pad onto the floor covering. This causes the gas to penetrate the floor covering, flow through it, and then leave it again due to the incoming gas flow. As it penetrates the floor covering, the gas absorbs any dirt-laden cleaning fluid and solids and carries them away. Depending on whether the gas is hot or cold gas, various possible embodiments of the method according to the invention arise, with the embodiment using hot gas being described as preferred.

[0099] The above descriptions apply to the device according to the invention for the version with hot gas that was experimentally tested and described in the examples. According to the invention, the application of hot gas can be realized in two variants. In the first variant, (undiluted) superheated steam is used as the hot gas, while in the second variant, hot gas unsaturated with water (diluted steam) is used. Both variants have in common that steam is generated in a steam generator. For this purpose, water is heated in the pressure-tight steam generation unit until an excess pressure of steam is reached. According to initial tests, this pressure is between 2 and 12 bar. The generated steam therefore has a temperature that is at or above the boiling point of water of approximately 100°C (at atmospheric pressure at the corresponding level).The water used to generate steam is preferably pure water, as steam leaves no traces on objects (and thus on the flooring) during evaporation and drying. However, small amounts of volatile ingredients, such as alcohols, fragrances, or disinfectants, do not impair this function. The use of deionized water is preferred for steam generation.

[0100] In the first variant, superheated steam is generated at a pressure of between 5 and 10 bar, for example 7.7 bar. This is applied, preferably in pulses, through the pad directly onto the floor covering. For this purpose, the valve is expediently used to open the steam pressure line from the steam generator to the space behind the pad, whereby the superheated steam escapes explosively from the steam generator and is applied to the floor covering through the pad. The valve is closed again as soon as the excess pressure has largely been reduced. The valve opening time is therefore expediently between 0.2 and 2 seconds, preferably between 0.5 and 1 second. The valve is kept closed until sufficient excess pressure has built up in the steam generator again. The closure time therefore depends on the steam generation capacity of the steam generator and is expediently between 0.5 and 10, preferably between 1 and 5 seconds.Once sufficient overpressure is established, the next steam burst can be applied. These steps can be repeated until the desired cleaning result is achieved. The device can be moved over the floor covering so that each steam burst covers the floor covering to be treated. Without wishing to be bound by this explanation, it is assumed that the cleaning fluid in the floor covering is heated by the expansion of the superheated steam, mixes with the steam, and is carried away with it.

[0101] In a second variant of the invention, the hot gas passed through the pad is not completely saturated with water vapor, i.e., more than 10% but less than 95%. The preferred degree of saturation (proportion of water vapor in the gas) is between 20 and 90%, particularly preferably between 25 and 70%. The hot gas preferably has a temperature of between 85 and 105°C, preferably between 90 and 100°C.

[0102] Without wishing to be bound by this explanation, it is assumed that hot gas, previously unsaturated with steam, is saturated with volatile components of the cleaning fluid, such as alcohol and water, and also displaces dirt particles, possibly contained in the cleaning fluid, from the floor covering. Under suitable conditions, this process can largely remove the cleaning fluid from the floor covering, and dirt can be bound to the pad or, if necessary, absorbed by the suction unit.

[0103] Mixed forms of these variants are possible, for example a hot gas made of diluted superheated steam.

[0104] Another benefit of applying the hot gas through the pad is that it allows the pad to glide more easily over the floor covering than with conventional pad machines. The higher the set pressure, the more easily the device according to the invention can glide over the floor covering on a steam cushion. However, the pressure should only be high enough for the pad to still absorb dirt loosened from the floor covering. The required pressure can also be optimized by providing aprons around the hot gas application unit.

[0105] The second function of the pad's movement across the floor covering is to absorb dirt into the pad. Due to the pad's structure, dirt particles and droplets stirred up or liquefied by the hot gas become trapped in the pad, particularly on the pad's textile threads, and adhere to them. If the dirt droplets are not yet completely dry, they can be further dried by the incoming unsaturated hot gas, thus allowing the dissolved dirt particles to adhere even more effectively to the pad.

[0106] The pad's second function can be further enhanced by bringing it into direct mechanical contact with the floor covering. For this purpose, the pad can be mounted on a rotating or vibrating body, which is moved while the hot gas is applied. Textile threads on the pad can then pass through the textile fibers of the floor covering. This can also facilitate better penetration of the hot gas into the floor covering.

[0107] Further steps may be added as optional or advantageous steps of the method according to the invention.

[0108] For example, the step of applying the cleaning agent can be preceded by a dry cleaning step, such as a suction step, with which in particular loose solids are removed from the textile floor covering before the cleaning agent is applied, so that cleaning agent can be saved, the service life of the pad can be extended or the cleaning process can be accelerated.

[0109] The intensity and depth of wetting can be improved by applying the cleaning agent to the floor covering with textile-covered, moistened rotating bodies, such as brush rollers or vibrating bodies. This is preferably achieved by using a rotating brush with coarser bristles, adapted to the nature of the textile floor covering. This brush has the task of deeply wetting the soiled fibers with the alcohol-based cleaning agent, distributing it over the entire surface so that the textile fibers are evenly moistened, and loosening existing bonds, preferably mechanically, to conserve resources. This step is best performed between the application of the cleaning agent via spray nozzles and its incorporation with a softer brush.If particularly intensive processing is desired, for example with very heavily soiled floor coverings or very stubborn dirt, the application step can be followed by a step of mechanical (intensive) incorporation using a second, softer brush or vibrating surface, which can also consist of a textile-covered rotating or flat vibrating body. This is preferably a roller body covered with a pad, the surface of which is equipped with microfiber threads. Due to the intensive contact of the body with the textile floor covering, for example the rotation of the roller body on the floor covering, whereby the threads of the pad press together and comb through the textile fibers of the floor covering, dirt is better removed from deep within the textile floor covering. Details of the properties are described above for the device according to the invention.However, the cleaning agent can also be incorporated during the application of the cleaning agent, for example when using rotating bodies that are subjected to cleaning agent.

[0110] By subjecting the floor covering to hot gas, considerable quantities of hot gas can be generated and released into the environment, depending on the intensity. To prevent the generated hot gas, including any dirt and cleaning agent still contained therein even after the dirt has been deposited on the pad, from escaping into the environment, the hot gas escaping from the floor covering can be extracted. For this purpose, an extraction step can be provided through extraction openings (in an extraction unit as described above) arranged in such a way that, if possible, the hot gas enriched with dirt coming from the floor covering can be extracted rather than the fresh hot gas. This can be achieved by sucking in the contaminated hot gas through extraction nozzles mounted around the unit for applying fresh hot gas and directing it into a chamber inside the device.There, the hot gas is condensed by cooling and / or the substances it contains are separated, for example, by filtration or centrifugation. If the condensable components are successfully separated from the gaseous and solid components, the condensate can be recycled and reused, for example, in the cleaning agent or the hot gas.

[0111] It is known that some floor coverings require maintenance treatment after or during cleaning. These treatments are known to those skilled in the art and can also be combined with the method according to the invention. Thus, additional care steps, such as incorporating lanolin into floor coverings containing new wool or applying waterproofing agents using the softer brush roller, can be performed.

[0112] After the device according to the invention has been moved with the pad over the area of ​​the floor covering to be treated, the floor covering only has a small amount of residual moisture, which essentially consists of condensed water vapor. Due to the heating of the floor covering by the hot gas, this residual moisture also evaporates quickly.

[0113] With the method according to the invention, a variety of advantages can be achieved individually or in combination with one another. The floor covering can be walked on without restrictions much sooner than with known methods based on spray extraction. This generally allows a hotel room to be reoccupied on the same day. The necessary wetting of the floor covering with cleaning fluid can be significantly reduced compared to known methods based on spray extraction for basic or intensive cleaning of textile floor coverings. The method according to the invention is therefore particularly suitable for basic cleaning. The cleaning performance of the method according to the invention is superior to cleaning with surfactants, enzymes and phosphates due to the properties of volatile solvents in conjunction with the outstanding dissolving power of, for example, alcohol (especially isopropanol).The use of steam to separate dirt from the applied cleaning fluid, which removes the cleaning agent used in this process through a physico-chemical process, leaving no residue and being environmentally friendly, avoids wastewater that would otherwise be generated when washing out surfactants and enzymes. This also saves a considerable amount of the valuable resource water. Furthermore, the unsaturated steam, with its ability to absorb moisture, ensures accelerated drying of the damp carpet, making it more accessible again sooner. Due to the rapid work sequence and the absence of cleaning fluid residue, the carpet cleaning process according to the invention eliminates the need for additional steps to rinse out the cleaning agent used. The invention therefore significantly reduces labor requirements and, if desired, also results in a significantly reduced overall working time compared to spray extraction.

[0114] Applying steam only to the damp textile floor prevents damage to the fibers because they can withstand thermal heat better when moist than dry textiles.

[0115] The possible embodiment of the inventive method using cold gas can be applied to textile surfaces which, due to their specific requirements, do not allow for greater moisture penetration. Unless stated otherwise below, the method using cold gas uses the same conditions as the method using hot gas. One change is that the pad is permeable to cold gas. However, the same materials are generally suitable as for hot-gas-permeable pads. The cold gas used is a gas with a significantly lower temperature than the hot gas described above. The same gases can be used as described for the hot gas. The temperature can be between 25 and 50°C, but is preferably 30-35°C. The hot gas outlet unit is replaced by a cold gas outlet unit capable of conveying cold gas into the space behind the pad and through the pad onto the floor covering.A steam generation unit is therefore usually not required or is set to generate low-temperature steam. A further change is that the process described above is carried out under negative pressure created by a suction unit. The various work steps take place one after the other, not with the entire device moving, but with the device stationary in a lowered position onto the partial area of ​​the textile floor covering covered by the device. A suction unit creates negative pressure on this area between the floor covering and the device during or after operation of the application and gas outlet units. Once the majority of the cleaning agent has been sucked away, the negative pressure is released again using the control system, the units involved are raised again, and the device is moved to the next partial area to be treated.

[0116] This version of the inventive method using cold gas is particularly characterized by the further increased economy in the use of cleaning agents while maintaining the same quality of cleaning performance. This is achieved by applying a smaller amount of aqueous cleaning agent with a consistently higher concentration of the volatile solvent to the textile floor covering prior to incorporation. This saturates the carpet fibers but leaves the carpet backing largely unwetted. The negative pressure ensures that all steps after the dirt has been removed from the fibers, including the application of cold gas, can take place at a significantly lower temperature.The low temperature of the gas allows an unsaturated, moist fiber to be intensively cleaned without any risk of harmful scorching, because the cold gas leaving the gas outlet unit is also able to transport the dirt released from the fiber into the collection pad.

[0117] Since the dissolving power of the alcohol with respect to the contaminated fiber is independent of temperature and the use of cooling devices for the alcohol-containing tanks is also provided in the previous device variants in order to keep alcoholic vapors to a minimum, a reduction in the temperature of the vapor does not prevent a reduction in the cleaning performance.

[0118] This low-temperature variant of the process with low moisture penetration of the floor covering makes this embodiment of the process according to the invention applicable to water-sensitive textile floor coverings, particularly for sensitive carpets, such as those with older, worn or brittle pile or also for older carpets with foam backing, where there is a risk of detachment from the screed due to moisture penetration.

[0119] A device suitable for the described cold gas version shares the external dimensions with the third device variant "Maxi", but differs from it in that not two, but only one working unit is required, which is, however, used across the entire width of the device in the appropriate sequence and on the entire surface of the floor covering covered by the device.

[0120] Given that the device operates at a standstill, it is necessary to have the option of arranging and controlling the actuators used in the respective work steps using suitable technical solutions so that the work steps (application and distribution of the cleaning fluid, unbundling and straightening of the fiber, incorporation for mechanical dirt removal as well as vapor deposition and dirt absorption in the pad) can be carried out sequentially over the entire area covered by the device.

[0121] Unwanted release of cleaning agent components, such as alcohol vapors, from the moistened floor covering is prevented by the rapid succession of the vaporization step to the moistening and incorporation of the cleaning agent into the floor covering. The steps according to the invention enable immediate absorption of the contaminated cleaning agent after moistening and incorporation, thus enabling rapid operation by moving the device over the floor covering to be cleaned.

[0122] Another advantage of the invention is the reduction of wastewater contaminated with surfactants, phosphates and enzymes, which are expensive, difficult to biodegrade and responsible for the increasing nutrient richness (eutrophication) in the waters.

[0123] The invention further relates to the use of an aqueous solution of volatile cleaning-active organic solvents, e.g., containing one or more C1-C5 alcohols, wherein the C1-C5 alcohol content of the solution should not exceed 39 wt.%, for moistening and cleaning textile floor coverings. Preferred aqueous solutions are described above.

[0124] The invention further provides an aqueous solution of volatile cleaning-active solvents, e.g., containing one or more C1-C5 alcohols, in which case the C1-C5 alcohol content of the solution should not exceed 39 wt.%, for cleaning a textile floor covering. In a preferred use, the aqueous composition contains alcohol and is cooled as described above. Preferred aqueous solutions are described above.

[0125] Another object of the invention is a method for cleaning textile floor coverings using a device with at least two units for processing the floor covering, wherein the units are moved upwards and downwards by vertical movement units during the cleaning process.

[0126] The method according to the invention is particularly effective in that the units used for cleaning are only activated precisely when they are needed. The targeted lowering and raising of the units is not necessary with the known devices and is also not described. In the case of the incorporation unit, this includes lowering the rotating or vibrating bodies onto the floor covering only during the incorporation step or only onto the part of the floor covering into which the incorporation is to take place. If they remained lowered while not needed, they would generate high frictional resistance. The same applies to the hot gas outlet unit, which would exhibit high frictional resistance, particularly in the case of pads with a large surface area, if it were not raised outside of its activation phase. It can therefore be lowered onto the floor covering when activated.

[0127] This lowering and raising of the units is performed by vertical motion units. The vertical movement (upward or downward) is preferably accomplished by activating / deactivating actuators with electromagnets and is triggered manually with a switch or automatically by a control system.

[0128] A further object of the invention is the use of a rotating or vibrating body, the surface of which is provided with a pad with textile threads, for cleaning a textile floor covering moistened with an alcohol-containing aqueous cleaning agent.

[0129] List of reference symbols

[0130] 1 storage container including pump for the cleaning agent

[0131] 2 storage tanks including pump for water to generate steam

[0132] 3 steam generators

[0133] 4 Steam outlet valve

[0134] 5 storage containers including pump for refatting impregnation agent

[0135] 6 Outer outlet nozzle for cleaning agent

[0136] 7 Inner outlet nozzle for cleaning agent actuator (8a, 8b, 8c)

[0137] electric motor

[0138] Outlet nozzle for refatting impregnation agent

[0139] WheelZRoller (11a, 11b, 11c, 11d)

[0140] Unit with rotating body for applying the cleaning agent

[0141] Hot gas outlet unit

[0142] Unit with rotating body for incorporating the cleaning agent

[0143] Device base a Extraction openings b Aprons

[0144] Guide bracket

[0145] Control unit

[0146] Extractor / Condenser a Pad supply roll in cassette, fresh, unwinding b Pad supply roll in cassette, dirty, rewinding

[0147] Example 1 - Simple prototype

[0148] A commercially available brush scrubber with different brush rollers for hard floors and carpets, "Model LAVOR SPRINTER" from Lavorwash, was modified as follows: Unless otherwise stated, all components of the SPRINTER were retained. Nozzles for applying the cleaning agent were attached to the front sides of the SPRINTER's mobile unit. These were connected to the lower collection container for the extracted dirty water, which had been converted into a storage container for the cleaning agent, via an additional pump. Furthermore, a surrounding frame was attached to the mobile unit at a height of approximately 3 cm. This frame was tiltably attached near the wheels of the mobile unit. At the front of the mobile unit, the frame was connected to the mobile unit via an electromagnet, which can be used to raise the front part of the mobile unit by approximately 1 cm above the frame.Two wheels are attached to the front of the frame to move the frame along the floor. This means that when the unit is raised (the brush roller is not in contact with the floor), it runs on four wheels.

[0149] The front cleaning agent nozzles were connected to the lower storage container of the SPRINTER via hoses. 0.75 l of a cleaning agent mixture consisting of 250 ml of ethanol and 500 ml of water was poured into the upper cleaning agent storage container with an outlet onto the brush roller. The SPRINTER's original blower motor for extracting the dirty cleaning agent from the carpet was removed. A water pump with a suction opening in the lower area of ​​the container was installed in the SPRINTER container that was originally used as a waste water collection container. The pump was electrically connected in parallel to the SPRINTER's application pump. A hose was laid from the discharge opening of the water pump to the additional nozzles for applying the cleaning agent that were mounted in front of the device. 1.5 l of the cleaning agent mixture (500 ml of ethanol and 1 l of water) was poured into the waste water container.

[0150] A VILEDA Steam PLUS steam mop pad was stretched over the entire soleplate of a Tefal Pro Express Ultimate GV9567 steam iron using the silk spacer accessory, which was sawn down to the frame. This spacer serves to secure the pad over the iron's steam outlet, ensuring it is firmly connected to the soleplate. The pad's distance from the soleplate and the steam outlet holes ensures the lateral mixing of air with the steam. The switch for ejecting the hot steam on the iron was relocated to the SPRINTER handle. The iron was attached to the rear of the SPRINTER using a 40x40 cm frame so that the pad rested on the carpet.The frame was mounted on the SPRINTER's mobile unit via a hinge and a Bowden cable operated by a second electromagnet so that it could be raised far enough for the pad to no longer rest on the carpet.

[0151] The steam generator of the "tefal Pro Express Ultimate GV9567" was also stored in a basket above the Sprinter's mobile section and connected to the Sprinter's power supply. The steam generator is pressure-tightly connected to the steam iron via a steam hose.

[0152] Example 2 - Cleaning process with ethanol-containing cleaning agent

[0153] The device manufactured according to Example 1 was placed on a velour carpet with a pile height of approximately 4 mm and connected to the power supply. The front part of the SPRINTER was lowered in the TI position so that the brush roller rested on the floor, while simultaneously the frame with the steam iron was lifted from the floor by the second electromagnet. While moving forward, cleaning agent was sprayed from the upper reservoir onto the brush roller and from the lower reservoir onto the carpet via the front additional nozzles in front of the device. The device was moved back and forth several times to roughly moisten the carpet.

[0154] For the second step, the brush roller was put into operation and the device was again pushed back and forth several times over the moistened area, whereby the cleaning agent was evenly distributed by the brush on and into the carpet pile.

[0155] For the third step, the brush roller was replaced with a second rotating body. It was made by shortening the approximately 1.5 cm long bristles of a brush roller by approximately 5 mm and then wrapping the resulting brush roller with a pad made from a microfiber wash mitt, as is commonly used for car washing. The pad has textile threads that extend towards the floor covering, similar to the pad on the VILEDA steam cleaner. The brush roller was started with the front part lowered and the rear part raised (frame with steam iron) and moved over the carpet. The cleaning agent was worked into the carpet pile via the textile threads. This step was carried out at the same movement speed for approximately four times as long as the second step. The pile of the carpet was then completely and evenly moistened with cleaning agent.In addition, the fibers had risen evenly in both the more and less frequently used areas. The floor had a distinct odor of ethanol.

[0156] For the fourth step, the front part of the device was raised using the front electromagnet so that the rotating body for the application was no longer resting on the floor covering, and the rear part was lowered using the second electromagnet so that the pad of the gas outlet unit was resting on the floor covering. The steam generation was then started using the switch on the device. After a few seconds, the required steam pressure had built up. The trigger for the iron's steam outlet valve, which was located in the handle of the SPRINTER, was then operated and hot gas was directed through the pad onto the floor covering for approximately 10 seconds. The device was moved across the floor at a speed of approximately 5 cm / s. This process was repeated for approximately as long as the application had taken. After this step, the carpet was only slightly damp and had at most a slight smell of alcohol. After approx.After 6 hours, the carpet was completely dry and walkable again. For the extremely intensive cleaning of a 6.2 sq m carpet area, 2.25 l of cleaning agent and approximately 1 l of pure water were used (possible reuse was not taken into account). The carpet pile was very evenly aligned after drying. Upon removing the pad, the discoloration revealed that the dirt from the carpet had accumulated from the tips of the pad's textile threads all the way to the inside. The dirt could be easily removed by washing the pad in the washing machine at 60°C, and the pad could be reused.

[0157] Example 3 - Cleaning with isopropanol-containing cleaning agent

[0158] Example 2 was repeated using isopropanol instead of ethanol. The result was the same.

Claims

AMENDED CLAIMS received by the International Bureau on 12 September 2025 (12.09.2025) 1. A method for cleaning a textile floor covering comprising a. applying an aqueous cleaning agent to the textile floor covering, and b. incorporating the cleaning agent and mechanically treating the textile floor covering, and c. moving a hot gas-permeable pad over the textile floor covering moistened with the cleaning agent while steaming the textile floor covering with hot gas through the pad, characterized in that the aqueous cleaning agent has a cleaning-active content of one or more C1-C5 alcohols of between 15 and 39 wt%.

2. Method according to claim 1 for cleaning a textile floor covering with a device having at least two units for processing the floor covering in a housing, wherein the units are moved upwards and downwards in the housing by vertical movement units during the cleaning process.

3. Use of an aqueous solution for carrying out the method according to claim 1, comprising a cleaning-active content of one or more C1-C5 alcohols of between 15 and 39 wt.% for moistening and cleaning a textile floor covering.

4. Use of a rotating or vibrating body, the surface of which is provided with a pad containing textile threads, for cleaning a textile floor covering moistened with an aqueous solution containing between 15 and 39 wt% of one or more C1-C5 alcohols, using hot gas to carry out the method according to claim 1.

5. Device for cleaning a textile floor covering with a housing comprising: a. a dispensing unit (12) for dispensing an aqueous cleaning agent onto the textile floor covering; b. a separate, height-adjustable incorporation unit (14) within the housing for mechanically treating the textile floor covering; c. a steam generation unit (3) for generating superheated or unsaturated steam; d. a height-adjustable hot gas outlet unit (13) within the housing with a hot gas-permeable pad movable over the textile floor covering for conveying the steam through the pad onto the textile floor covering; and e. a vertical movement unit for lowering and raising the units.

6. Device according to claim 5, characterized in that it has a suction unit (18) with suction openings (15a) in the device base (15) for suctioning liquids and vapors, and skirts (15b) surrounding the entire device. 31 AMENDED SHEET (ARTICLE 19) 7. Device according to one of claims 5 and 6, characterized in that it further comprises a control unit (17) for controlling the dispensing of the cleaning agent and the generation of steam.

8. Device according to claim 6, characterized in that it has two dispensing units (12), two incorporation units (14) and two hot gas outlet units (13).

9. Device according to claim 5, characterized in that the pad is stretched in an exchangeable cassette in a way that allows it to be unrolled on a supply roll for fresh pad and rolled up on a supply roll for soiled pad. 32 AMENDED SHEET (ARTICLE 19)

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