SUPPLYING LIQUID TO AT LEAST ONE AREA OF A SURFACE TO BE CLEANED

Abstract

In the context of vacuum cleaning, a suction head is provided, which includes a housing that is couplable to an air suction source of a vacuum cleaner, and two brushes in a substantially parallel arrangement in the housing. The brushes are rotatable about a rotation axis and configured to interact with a surface to be cleaned. The suction head is further equipped with a wetting arrangement that enables a direct supply of liquid from at least one liquid supplying position to at least one area of the surface to be cleaned, where the at least one liquid supplying position is in an area between the brushes and at a level of the rotation axes of the brushes or closer to surface level.

Claims

1. A suction head configured to be applied in a vacuum cleaner and to perform a cleaning action on a surface to be cleaned, the suction head comprising: a housing that includes a coupling area configured to enable coupling of the housing to an air suction source of the vacuum cleaner, two brushes in a substantially parallel arrangement in the housing, wherein each of the two brushes is rotatable about a rotation axis and is configured to interact with the surface to be cleaned, and a wetting arrangement that is arranged and configured to enable a direct supply of liquid from at least one liquid supplying position to at least one area of the surface to be cleaned, wherein the at least one liquid supplying position is in an area between the two brushes and at a level of the rotation axes of the two brushes or closer to surface level.

2. The suction head according to claim 1, wherein the at least one liquid supplying position is at a bottom surface portion of the suction head, and wherein the atleast liquid supplying position is arranged and configured to face the surface to be cleaned at a distance of at least 2 mm and at most 6 mm to the surface.

3. The suction head according to claim 1, wherein the wetting arrangement is arranged and configured to enable the direct supply of liquid from at least two liquid supplying positions distributed over the suction head in a direction (l) in which the rotation axes of the two brushes extend.

4. The suction head according to claim 1, further comprising an elongated intermediate component that is located in the area between the two brushes and that optionally comprises two portions configured to cover portions of the two brushes.

5. The suction head according to claim 4, wherein the elongated intermediate component, at the position of a top side thereof, is suspended from a portion of the housing.

6. The suction head according to claim 4, wherein the at least one liquid supplying position is at a bottom surface portion of the elongated intermediate component, and wherein the bottom surface portion of the elongated intermediate component is arranged and configured to face the surface to be cleaned.

7. The suction head according to claim 6, wherein the wetting arrangement comprises a conduit system configured to transport the direct supply of liquid and to let out the direct supply of liquid at the at least one liquid supplying position.

8. The suction head according to claim 7, wherein the conduit system comprises at least one conduit extending through the elongated intermediate component.

9. The suction head according to claim 7, wherein the conduit system comprises at least one main conduit and at least one branch conduit, and wherein the at least one branch conduit is coupled to the at least one main conduit and extends from the at least one main conduit towards the at least one liquid supplying position.

10. The suction head according to claim 9, comprising a restriction element in fluid communication with the at least one main conduit and the at least one branch conduit, wherein the restriction element is provided with a restriction opening configured to allow the direct supply of liquid to pass in a direction from the at least one main conduit towards the at least one branch conduit, and wherein the restriction element or an assembly of components in which the restriction element is included is removably arranged in the suction head.

11. The suction head according to claim 1, comprising at least one wheel that is rotatably arranged on the suction head, wherein the at least one wheel is configured to be in contact with the surface to be cleaned, and wherein the wetting arrangement is further arranged and configured to enable the direct supply of liquid to the at least one wheel.

12. The suction head according to claim 11, wherein the wetting arrangement is arranged and configured to enable the direct supply of liquid to the at least one wheel at the position of a tread of the at least one wheel, from outside of the at least one wheel.

13. The suction head according to claim 11, wherein the at least one wheel is arranged so that the two rotating brushes are enabled to interact with the wheel during operation of the suction head.

14. The suction head according to claim 11, wherein the at least one wheel is located in the area between the two brushes.

15. Cordless A cordless vacuum cleaner, comprising the suction head of claim 1.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The invention will now be explained in greater detail with reference to the figures, in which equal or similar parts are indicated by the same reference signs, and in which:

[0022] FIG. 1 diagrammatically shows components of a wet vacuum cleaner according to an embodiment of the invention and a portion of a floor having a surface to be cleaned,

[0023] FIG. 2 diagrammatically shows a view of a longitudinal section of a suction head according to an embodiment of the invention, taken at a position between two brushes which are included in the suction head,

[0024] FIG. 3 shows an enlarged detail of FIG. 2,

[0025] FIG. 4 diagrammatically shows a perspective top view of a portion of the suction head,

[0026] FIGS. 5 and 6 diagrammatically show views of a cross-section of the suction head, taken at different longitudinal positions on the suction head,

[0027] FIG. 7 shows an enlarged detail of FIG. 6, and

[0028] FIG. 8 illustrates an optional set-up of a conduit system of a wetting arrangement that is included in the suction head.

DETAILED DESCRIPTION OF THE EMBODIMENTS

[0029] FIG. 1 illustrates the design of a wet vacuum cleaner 100 according to an embodiment of the invention. The particular vacuum cleaner represented in FIG. 1 and described in the following is just one example of many types of vacuum cleaners which are feasible in the framework of the invention. In this respect, it is noted that the invention does not only relate to wet vacuum cleaners, but also to other types of vacuum cleaners such as wet/dry vacuum cleaners having a dry cleaning function besides a wet cleaning function.

[0030] The wet vacuum cleaner 100 is configured to be used for the purpose of subjecting a surface 10 such as a floor surface to a wet cleaning action. FIG. 1 shows the vacuum cleaner 100 in a normal, operational orientation relative to the surface 10 to be cleaned. The use in the present text of a term having an orientation aspect is to be understood in relation to this normal, operational orientation of the vacuum cleaner 100 relative to the surface 10 to be cleaned, wherein it is assumed that the surface 10 is at a bottom position and the vacuum cleaner 100 is placed on the surface 10.

[0031] At a side that is supposed to face the surface 10 during operation of the vacuum cleaner 100, the vacuum cleaner 100 comprises a suction head 101 accommodating two brushes 20 which are configured to interact with the surface 10 during operation of the vacuum cleaner 100. In the following, it is assumed that each of the brushes 20 is provided in the form of a roller that is rotatable about a rotation axis 21 that is defined by a central longitudinal axis of the roller, and that each of the brushes 20 comprises a core element 22 and flexible microfiber elements 23 arranged on the core element 22, which does not alter the fact that other embodiments of the brushes 20 are possible as well. The brushes 20 may be identical, but this is not necessary in the context of the invention. As indicated in FIG. 1 by means of curved arrows depicted at the position of the brushes 20, the brushes 20 are arranged so as to be rotatable in opposite directions with respect to each other about their respective rotation axes 21. The suction head 101 comprises a housing 30 that is configured to partially cover the brushes 20. The housing 30 can be made of a plastic material, for example.

[0032] Besides the suction head 101, the vacuum cleaner 100 comprises a body portion 102 that is configured to be taken hold of by a user of the vacuum cleaner 100. Preferably, the suction head 101 and the body portion 102 are removably couplable to each other. The body portion 102 can be shaped in any appropriate way. The outline of the body portion 102 as shown in FIG. 1 is of a diagrammatical nature only. It is practical if the body portion 102 comprises a handle so that a user can easily take hold of the body portion 102 and move the vacuum cleaner 100 across the surface 10 to be cleaned as desired.

[0033] For the purpose of driving the brushes 20 during operation of the vacuum cleaner 100, the vacuum cleaner 100 is equipped with a suitable electric drive mechanism (not shown). For the purpose of powering the drive mechanism and probably also other components of the vacuum cleaner 100, the vacuum cleaner 100 may be connectable to the mains and/or may be equipped with a suitable battery arrangement. Preferably, the vacuum cleaner 100 is a cordless device comprising a rechargeable battery arrangement, in which case it may further be practical if the vacuum cleaner 100 is part of a set including a charging dock besides the vacuum cleaner 100. Such a set may also include a flushing tray that can be used for the purpose of cleaning the brushes 20. In case the vacuum cleaner 100 is not equipped with a battery, a simple dock that is without charging ability may be provided for receiving and holding the vacuum cleaner 100 while the vacuum cleaner 100 is not being operated.

[0034] The body portion 102 of the vacuum cleaner 100 includes a liquid reservoir 40 that serves for containing a liquid such as water or a mixture of water and a cleaning agent, and a liquid supply mechanism 41 that serves for supplying the liquid to a wetting arrangement 42 of the suction head 101 during operation of the vacuum cleaner 100. The liquid supply mechanism 41 may comprise any suitable type of pump arrangement, for example, or may be configured to enable displacement of the liquid as desired under the influence of gravity. In the shown example, the wetting arrangement 42 of the suction head 101 is configured to enable both a direct supply of liquid to areas of the surface 10 to be cleaned and a direct supply of liquid to two wheels 90 of the suction head 101 (see FIGS. 2, 3, 5 and 6), as will be explained later in more detail. Further, in the shown example, the suction head 101 comprises an elongated intermediate component 25 that is located in an area 24 between the brushes 20 and that comprises two concavely curved portions configured to cover portions of the brushes 20, and the wetting arrangement 42 comprises a conduit system 43 that is partially arranged in the elongated intermediate component 25 and that is configured to transport the liquid and to let out the liquid to the areas of the surface 10 and to the two wheels 90. In FIG. 1, the liquid reservoir 40, the liquid supply mechanism 41 and the wetting arrangement 42 of the suction head 101 are indicated by means of dotted lines. It is practical if the liquid reservoir 40 is removably coupled to the body portion 102 so that a user is enabled to separate the liquid reservoir 40 from the body portion 102 when it is desired to take the liquid reservoir 40 to a place where the liquid reservoir 40 is to be filled with liquid.

[0035] The body portion 102 of the vacuum cleaner 100 further includes a dirt reservoir 50 that serves for receiving and accumulating wet dirt 11 that is picked up from the surface 10 by the brushes 20 during operation of the vacuum cleaner 100. The dirt reservoir 50 can be configured in numerous ways as conventionally available for accumulating wet dirt from the incoming dirt 11 that is picked up from the surface 10 such as for instance a cyclonic arrangement or a tube-in-cup arrangement. The body portion 102 includes a vacuum mechanism 60 configured to create underpressure that is functional to enable transport of the dirt 11 from the area where the brushes 20 are located to the dirt reservoir 50 in the body portion 102, through an outlet opening 31 in a surface 32 of the housing 30 facing the brushes 20 and a suction channel 51 extending from the outlet opening 31 to the dirt reservoir 50. As can be seen in the view of the portion of the suction head 101 in FIG. 4, the housing 30 includes a coupling area 33 that is configured to enable coupling of the housing 30 to the assembly of the suction channel 51, the dirt reservoir 50 and the vacuum mechanism 60 in the body portion 102 of the vacuum cleaner 100. The outlet opening 31 is in fluid communication with this coupling area 33.

[0036] Basic aspects of the way in which the wet vacuum cleaner 100 is operated are as follows. During operation, the brushes 20 are driven so as to rotate and the liquid supply mechanism 41 is activated so as to supply liquid to the wetting arrangement 42 of the suction head 101 so that liquid may be let out to the surface 10 to be cleaned and to the two wheels 90. Any stains as may be present on an area of the surface 10 that is within reach of the brushes 20 are detached under the influence of the liquid and agitation by the brushes 20, and dirt particles and dust as may be present on the area of the surface 10 are removed along with the liquid and conveyed to the dirt reservoir 50, passing through the outlet opening 31 and the suction channel 51 in the process. The dirt 11 is picked up from the surface 10 by tip portions of the microfiber elements 23 of the brushes 20 and is flung away from the tip portions as the brushes 20 rotate, at a position where the tip portions move out of contact to the surface 10.

[0037] As illustrated in FIG. 1, the vacuum cleaner 100 may be equipped with a user interface 70, which user interface 70 may include an on/off button 71, for example. The vacuum cleaner 100 may further comprise a controlling system 80 including a microcontroller that is programmed to put the brushes 20 in motion and to activate both the liquid supply mechanism 41 and the vacuum mechanism 60 in reaction to input received from the user through the user interface 70 to that end.

[0038] FIGS. 2-8 serve to illustrate aspects of a suction head 101 according to an embodiment of the invention, especially aspects of the wetting arrangement 42 of the suction head 101. It can be seen in FIGS. 2 and 4 that the conduit system 43 of the wetting arrangement 42 comprises two main conduits 44, 45 which are located in different halves of the suction head 101 as seen in a longitudinal direction l being the direction which the rotation axes 21 of the brushes 20 extend, and which are couplable to the liquid supply mechanism 41. Further, the conduit system 43 comprises four branch conduits 46, 47, 48, 49, namely, as seen from left to right in FIG. 2, i) a branch conduit 46 that is coupled to a first one 44 of the main conduits 44, 45, that is configured to let out liquid to one of the wheels 90, and that extends from the first one 44 of the main conduits 44, 45 to the wheel 90, ii) a branch conduit 47 that is also coupled to the first one 44 of the main conduits 44, 45, at a longitudinal position more or less between the wheel 90 and the outlet opening 31, that is configured to let out liquid to a first area of the surface 10 to be cleaned, and that extends from the first one 44 of the main conduits 44, 45 to the surface 10, iii) a branch conduit 48 that is coupled to a second one 45 of the main conduits 44, 45, at a longitudinal position more or less between another wheel 90 and the outlet opening 31, that is configured to let out liquid to a second area of the surface 10 to be cleaned, and that extends from the second one 45 of the main conduits 44, 45 to the surface 10, and iv) a branch conduit 49 that is also coupled to the second one 45 of the main conduits 44, 45, that is configured to let out liquid to the other wheel 90, and that extends from the second one 45 of the main conduits 44, 45 to the wheel 90.

[0039] The branch conduits 47, 48 which are configured to let out liquid to the surface 10 to be cleaned are arranged to partially extend through the elongated intermediate component 25, and the liquid supplying positions where the liquid is let out to the surface 10 are at a bottom side of the elongated intermediate component 25, i.e. at a bottom surface portion 26 of the elongated intermediate component 25 that is arranged and configured to face the surface 10 to be cleaned. In this respect, it is noted that in general, in the context of the invention, the liquid supplying positions where the liquid is let out to the surface 10 are at a level of the rotation axes 21 of the brushes 20 or closer to surface level, i.e. at the level of the rotation axes 21 of the brushes 20 or at a lower level.

[0040] Letting out liquid to the surface 10 at liquid supplying positions which are distributed along the brushes 20 in the longitudinal direction I is a factor in achieving that the brushes 20 are sufficiently wetted, without any dry or nearly-dry areas which might render the cleaning action less effective. Letting out liquid to the wheels 90 during operation of the suction head 101 results in keeping the wheels 90 wet and clean, so that any negative influences on the results of the action of cleaning the surface 10 following from the fact that the surface 10 is contacted by the wheels 90 are avoided. It can be seen in FIGS. 2 and 3 that the position at which the liquid is let out to a wheel 90 is a position right above the wheel, such that the liquid can be received by the wheel 90 at the position of the tread 91 thereof.

[0041] FIG. 5 shows another advantageous aspect of the design of the suction head 101 according to the embodiment of the invention, which resides in the fact that each of the two wheels 90 is arranged so as to be in contact with the brushes 20, especially with the microfiber elements 23 of the brushes 20. In the first place, this contributes to keeping the wheels 90 clean. In the second place, this contributes to realizing that the brushes 20 are wetted along their length, i.e. their dimension in the longitudinal direction I.

[0042] FIG. 6 illustrates the advantageous option of the at least one liquid supplying position for letting out liquid to the surface 10 to be cleaned being at a bottom surface portion of the suction head 101 that is arranged and configured to face the surface 10 at a distance of at least 2 mm and at most 6 mm to the surface 10. By having only a small space between the surface 10 and the bottom surface portion of the suction head 101, it is achieved that the bottom surface portion of the suction head 101 is effectively kept clean. It is practical if the bottom surface portion of the suction head 101 that is arranged and configured to face the surface 10 at the relatively small distance to the surface 10 as mentioned comprises the bottom surface portion 26 of the elongated intermediate component 25.

[0043] On the basis of the foregoing, an overview of the advantageous aspects of the small space between the surface 10 to be cleaned and the bottom surface portion of the suction head 101 is provided: [0044] The liquid beneath the bottom surface portion bridges with the surface 10 and cleans the bottom surface portion by means of the surface tension, capturing small dirt particles that could adhere to the bottom surface portion. [0045] The flow of clean liquid from the different positions at which the liquid is let out has a direct cleaning effect on the bottom surface portion, especially on the bottom side of the elongated intermediate component 25. [0046] The movement of the suction head 101 results in the area underneath the bottom surface portion being in constant interaction with the brushes 20.

[0047] It is further noted that it is advantageous if the surface 32 of the housing 30 facing the brushes 20 is arranged so as to cover the brushes 20 at only a minimal distance, as in that case, the suction force is effectively invoked in the suction head 101, as a result of which air speed along the surface 32 can be relatively high, which also contributes to keeping the surface 32 clean, besides the fact that there is practically no room where dirt might build up.

[0048] In order to promote equal distribution of the liquid over the respective branch conduits 46, 47, 48, 49, it is practical if a restricted liquid passage 27 is present at an interface of the main conduits 44, 45 and the respective branch conduits 46, 47, 48, 49, as can best be seen in FIG. 7. The fact is that the restricted liquid passages 27 function to prevent drainage of the main conduits 44, 45 at the position of the branch conduit 47, 48 that comes first as seen in a downstream direction, which would hamper the supply of fluid to the other branch conduit 46, 49. Hence, on the basis of the presence of the restricted liquid passages 27, controlled retrieval of liquid from the main conduits 44, 45 at the positions where the branch conduits 46, 47, 48, 49 are coupled to the main conduits 44, 45 is realized.

[0049] FIG. 8 illustrates an option according to which a main conduit 44 is more or less dimensioned so as to serve as a buffer of the liquid 15, and according to which a restriction element 28 is applied at the position where the respective branch conduits 46, 47 are coupled to the main conduit 44. In the shown example, the restriction element 28 comprises a strip that is provided with two restriction openings. The restriction openings are dimensioned so as to realize restricted liquid passages 27 which are configured to create a flow of droplets of the liquid 15 rather than a continuous flow. Preferably, the restriction element 28 or an assembly of components in which the restriction element 28 is included is removably arranged in the suction head 101 so that the restriction element 28 or the entire assembly may be removed by a user from time to time for cleaning purposes. Cleaning the restriction element 28 and possibly also adjoining components on a regular basis may especially be helpful in avoiding that the restriction openings get clogged and that the supply of liquid 15 to the wheels 90 and the surface 10 to be cleaned is thereby hindered.

[0050] Although both the option of directly supplying liquid 15 to at least one area of the surface 10 to be cleaned and the option of directly supplying liquid 15 to the at least one wheel 90 are illustrated and explained in the context of a single embodiment of the suction head 101 according to the invention, it is to be understood that the options can be applied independently. Further, it is noted that additionally or alternatively to the option of directly supplying liquid 15 to the at least one wheel 90, an option of directly supplying liquid 15 to a position in the suction head 101, such as a position on one or both of the brushes 20, is feasible in the context of the invention. Generally speaking, the wetting arrangement 42 may be realized in any suitable way. For instance, it is possible to design the wetting arrangement 42 with a functionality to temporarily stop the supply of liquid to the at least one wheel 90 if so desired. This may be useful in view of a situation in which a type of surface 10 to be cleaned requires more than an average amount of liquid, this may allow a user to manually initiate a cleaning action of the at least one wheel 90 from time to time, etc.

[0051] When the suction head 101 comprises an elongated intermediate element 25 covering a portion of the brushes 20 from the bottom side of the suction head 101, as is the case in the shown embodiment of the suction head 101, it may be beneficial to use the elongated intermediate element 25 to accommodate at least a portion of one or more conduits of a conduit system 43 of the wetting arrangement 42, but this is not essential in the context of the invention.

[0052] It will be clear to a person skilled in the art that the scope of the invention is not limited to the examples discussed in the foregoing, but that several amendments and modifications thereof are possible without deviating from the scope of the invention as defined in the attached claims. It is intended that the invention be construed as including all such amendments and modifications insofar they come within the scope of the claims or the equivalents thereof. While the invention has been illustrated and described in detail in the figures and the description, such illustration and description are to be considered illustrative or exemplary only, and not restrictive. The invention is not limited to the disclosed embodiments. The drawings are schematic, wherein details which are not required for understanding the invention may have been omitted, and not necessarily to scale.

[0053] Variations to the disclosed embodiments can be understood and effected by a person skilled in the art in practicing the claimed invention, from a study of the figures, the description and the attached claims. In the claims, the word comprising does not exclude other steps or elements, and the indefinite article a or an does not exclude a plurality. Any reference signs in the claims should not be construed as limiting the scope of the invention.

[0054] Elements and aspects discussed for or in relation with a particular embodiment may be suitably combined with elements and aspects of other embodiments, unless explicitly stated otherwise. Thus, the mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage.

[0055] The terms comprise and include as used in this text will be understood by a person skilled in the art as covering the term consist of. Hence, the term comprise or include may in respect of an embodiment mean consist of, but may in another embodiment mean contain/have/be equipped with at least the defined species and optionally one or more other species.

[0056] Notable aspects of the invention are summarized as follows. In the context of vacuum cleaning, a suction head 101 is provided, which is of the type comprising: a housing 30 that is couplable to an air suction source 60 of a vacuum cleaner 100, and two brushes 20 in a substantially parallel arrangement in the housing 30, wherein each of the brushes 20 is rotatable about a rotation axis 21 and is configured to interact with a surface 10 to be cleaned. The suction head 101 is further equipped with a wetting arrangement 42 that is arranged and configured to enable a direct supply of liquid 15 from at least one liquid supplying position to at least one area of the surface 10 to be cleaned, wherein the at least one liquid supplying position is in an area 24 between the brushes 20 and at a level of the rotation axes 21 of the brushes 20 or closer to surface level.