CN115104953A

CN115104953A - Suction head for vacuum cleaner

Info

Publication number: CN115104953A
Application number: CN202210247390.7A
Authority: CN
Inventors: F·埃斯皮恩·弗兰科; I·B·布拉达
Original assignee: Koninklijke Philips NV
Current assignee: Fansongni Holdings Ltd
Priority date: 2021-03-17
Filing date: 2022-03-14
Publication date: 2022-09-27
Also published as: WO2022194631A1; CN218870144U; EP4059405A1; EP4262506A1; JP2024508192A; KR20230133397A; AU2022240881A1

Abstract

A suction head (101) configured to be applied in a vacuum cleaner and to perform a cleaning action on a surface (10), and comprising a housing (30) and two rotatable brushes (20) arranged substantially parallel in the housing (30), a surface (32) of the housing (30) facing the brushes (20) comprising two adjacent concavely curved regions (34, 35), wherein each of these regions (34, 35) covers a portion of a respective one (20a, 20b) of the brushes (20). Furthermore, the surface (32) is provided with an outlet opening (31) in fluid communication with a coupling region (33) of the suction head (101), the outlet opening (31) being located at an interface position of the concave curved regions (34, 35) and being dimensioned to cover only a portion of the length of the brush (20).

Description

Suction head for vacuum cleaner

Technical Field

The invention relates to a suction head configured to be applied in a vacuum cleaner and to perform a cleaning action on a surface, the suction head comprising: a housing comprising a coupling region configured to enable coupling of the housing to an air suction source of a vacuum cleaner; and two brushes arranged substantially in parallel in the housing, wherein each brush is rotatable about an axis of rotation and configured to interact with a surface to be cleaned, and wherein each brush is designed to be able to pick up liquid from the surface.

Furthermore, the invention relates to a cordless vacuum cleaner comprising a suction head as described above.

Background

Vacuum cleaners are known for removing dirt from a surface to be cleaned. The term "soil" as used herein should be understood to encompass any contaminants that may be present on a surface and that may be removed under the influence of a vacuum cleaning action, possibly in combination with other cleaning actions such as mopping. Practical examples of this include any kind of dust and small particles, as well as wet contaminants, such as spilled beverages. One practical example of a surface to be cleaned is a floor, wherein the floor may be any type of floor, such as a wooden floor, a carpet floor, a tile floor, etc.

Generally, a vacuum cleaner has a vacuum cleaner head or suction head, which is the part of the vacuum cleaner in which the actual process of picking up dirt from a surface to be cleaned takes place and which, therefore, is to be placed on or at least close to the surface. Furthermore, vacuum cleaners generally comprise a main body portion which includes a dirt accumulation region; and means configured to act on the suction head such that there is suction within the suction head during operation of the vacuum cleaner. The suction force is used to facilitate transport of dirt picked up from the surface towards a dirt accumulation region during operation of the vacuum cleaner, wherein the dirt is caused to pass through an outlet opening in the housing of the suction head. Suction may also be active in the actual process of picking up dirt from the surface. In another aspect, the suction head may be provided with at least one movable part for interacting with the surface to pick up dirt, such as at least one rotatable brush, which may act as an agitator for the dirt, and which may be particularly configured to assist in removing the dirt from the surface and directing the dirt towards the outlet opening.

WO2011/083373a1 discloses a cleaning device for removing particles from a surface, comprising a spraying means for spraying droplets of a working fluid, a rotatable brush having flexible brush elements, an inlet for receiving dirty air, such as air loaded with particles, and a cleaning unit. The cleaning unit is adapted to separate at least part of the working fluid droplets from the air. During operation, the rotatable brush is wetted by the working fluid. The brush is sized and rotated at a speed such that droplets of the working fluid are expelled from the flexible brush elements into the coalescing space of the apparatus as a mist of droplets. Dirty air received by the inlet may be received by the coalescing space to form coalesced particles of droplets and particles in the dirty air that are discharged from the brush element, the coalesced particles being transportable from the coalescing space to the cleaning unit.

WO2012/107876a1 discloses a cleaning device comprising: a head having an open side facing a surface to be cleaned; and at least one brush for contacting a surface to be cleaned, the at least one brush being rotatably arranged in the head. At least one brush has a plurality of bristles, wherein the bristles can be extremely soft and flexible. In this case, the cleaning action of the surface is not performed by scrubbing the surface, but by alternately bringing the bristles into and out of contact with the surface during brush rotation. In particular, during one revolution of the brush, the bristles remove particles and/or droplets from the soiled surface and, after reaching a position where they do not contact the surface and can be fully extended, they are thrown away. In the head of the cleaning device, where the brush is arranged, means are provided for receiving the particles and/or droplets and for possibly transporting the particles and/or droplets towards a collecting space thereof. The cleaning device may be equipped with means for effecting suction at the head so as to direct the particles and/or droplets in a desired direction once they are released from the bristles. Furthermore, the cleaning device may be configured to supply cleaning liquid to the rotating brush to promote adhesion of particles to the bristles and/or to achieve an additional cleaning effect on the surface to be cleaned.

WO2017/071727a1 discloses a vacuum cleaner head comprising a housing having a vacuum suction region and first and second rollers configured to be positioned against a surface to be cleaned, wherein each of the first and second rollers is configured to pick up dirt from the surface and transport it to the vacuum suction region in the housing of the vacuum cleaner head when rotated and moved over the surface during operation. A vacuum suction zone is defined between the outlet opening and the first and second rollers. When the vacuum cleaner head is used in a vacuum cleaner and the vacuum cleaner is operated, an air flow is generated through the vacuum suction zone to the outlet opening. The vacuum cleaner head may further comprise a liquid dispenser for dispensing liquid onto the surface to be cleaned, and the vacuum cleaner head may further comprise a liquid dispenser for dispensing liquid onto at least one of the first roller and the second roller. Thus, the surface to be cleaned may be wetted to facilitate removal of debris from the surface.

In the field of suction heads for wet vacuum cleaning, surface contamination of these suction heads is a problem. The combination of liquid and debris is a good formulation for depositing dirt on the suction head surface, including the brush-facing surface, and will be referred to hereinafter as the inner surface. Such contamination may be difficult to remove. Incompletely dried deposits are a good climate for microbial growth and odor generation. The user of the suction head may perceive that both are unhygienic. In some cases, the suction head needs to be subjected to a cleaning action after use or multiple uses.

Disclosure of Invention

In general, it is an object of the invention to provide measures which aim to achieve good cleaning results for performing a vacuum cleaning action on a surface. Furthermore, it is an object of the invention to provide measures which are intended to prevent contamination of the suction head.

In view of the above, the present invention provides a suction head configured to be applied in a vacuum cleaner and to perform a cleaning action on a surface, the suction head comprising: a housing including a coupling area configured to enable coupling of the housing to an air suction source of a vacuum cleaner; and two brushes arranged substantially in parallel in the housing, wherein each brush is rotatable about an axis of rotation and configured to interact with a surface to be cleaned, and wherein each brush is designed to be able to pick up liquid from the surface, wherein a brush-facing surface of the housing comprises two adjacent concave curved regions, wherein each concave curved region covers a part of one respective brush, wherein the brush-facing surface of the housing is provided with an outlet opening in fluid communication with the coupling region, and wherein the outlet opening is located at an interface position of the concave curved regions and the outlet opening is dimensioned to cover only a part of a dimension of the brush in a longitudinal direction, the longitudinal direction being a direction in which the axis of rotation of the brush extends.

As can be seen from the foregoing definitions of the suction head of the present invention, various features are applicable to the suction head. The background of these features will be described below. According to one basic insight of the invention, in order to keep the inner surfaces of the suction head as clean as possible during use of the suction head, it is advantageous to keep the air velocity along the surfaces as high as possible. There are three recognized methods of increasing air velocity: i) creating a high negative pressure by creating a resistance between the environment and the air suction source, ii) forcing the air flow through a narrow gap, and iii) applying a high suction power. The latter option is not interesting in the context of battery-powered vacuum cleaners.

In view of the above, a first aspect of the method of the present invention is to create a narrow gap, thereby increasing the air velocity and negative pressure. The invention may thus relate to encapsulating the brush in an area of the brush that does not face the surface to be cleaned or is not exposed to the outlet opening in the brush-facing surface of the housing. This aspect is based on the following features: the brush-facing surface of the housing includes two adjacent concave curved regions, wherein each concave curved region overlies a portion of a respective brush.

A second aspect of the method of the invention is to locate the outlet opening in the brush-facing surface of the housing at an advantageous position in the suction head and to keep the size of the outlet opening limited. This aspect is based on the following features: the outlet opening is located at the interface position of the concavely curved region and is dimensioned to cover only a portion of the length of the brush (i.e. the dimension of the brush in the longitudinal direction, which is the direction in which the rotational axis of the brush extends). This is in contrast to prior art solutions, in which the outlet opening typically extends along (almost) the entire length of the brush, i.e. the entire dimension of the brush in the direction of the longitudinal axis of the brush.

Preferably, each concave curved region on the brush-facing surface of the housing follows the operating profile of a portion of one respective brush at a distance of at most 10 mm. It is even more preferred if the above-mentioned distance is in the range of 0mm to 2mm in order to obtain an air velocity along the surface of the housing which may really involve a cleaning effect on the surface. The narrow gap thus obtained also relates to a cleaning effect based on the fact that there is practically no space in which dirt can accumulate.

Furthermore, it is beneficial if a narrow gap is created along as large a portion of the brush as possible. In view of this, it is advantageous if each concavely curved region on the brush-facing surface of the housing covers at least a part (upper half of the brush) at least as one respective brush. Preferably, at least 65% of the dimension of each brush about the respective axis of rotation is covered by a distance in the range 0mm to 2 mm. Furthermore, each concave curved region on the brush-facing surface of the housing may be made to cover a respective brush along the entire length of the brush.

In a practical embodiment of the suction head according to the invention, the operative shape of each brush is substantially cylindrical with a circular periphery, in other words the operative shape of the brush is substantially roller-like, which may be an elongated roller. In this case, in order to have a desired encapsulation of as many brushes as possible, it is advantageous if each concave curved area on the brush-facing surface of the housing covers one respective brush at the location of a part of the curved operating contour of the brush, and if the brush-facing surface of the housing also comprises an area covering the ends of the brushes.

It is also practical if the suction head comprises an airflow directing member (the airflow directing member comprising a tubular element in fluid communication with an outlet opening in the brush-facing surface of the housing and extending towards the coupling region). According to the invention, it is particularly possible that the air flow guide member comprises cuspids at the interface positions of concave curved areas on the brush-facing surface of the housing, which cuspids are in fluid communication with the outlet opening in the surface of the housing and extend on the sides of the tubular element, which are opposite sides in a direction perpendicular to the longitudinal direction of the tubular element. Wherein the provision of the cuspids helps to achieve a smooth introduction of air into the tubular element and avoids the deposition of dirt that would otherwise be expected to occur.

One measure aimed at preventing contamination of the wall of the tubular element is implemented in the following configuration: a portion of the wall of the tubular element located at a position above the outlet opening in the brush-facing surface of the housing is oriented non-perpendicularly with respect to the flow direction, which is an upward direction from the surface to be cleaned through the outlet opening and between the brushes. Avoiding sharp transitions and gradually bending the airflow to follow the orientation of the tubular element are design-related aspects, based on which the deposition of dirt is avoided. Furthermore, in this respect, it is advantageous if, at the interface position of the concave curved region on the brush-facing surface of the housing, a portion of the wall of the tubular element, seen in cross-section of the tubular element, is substantially arc-shaped.

Another measure aimed at having a narrow gap around the brushes consists in applying an elongated intermediate member, which is located in the area between the brushes and comprises two concave curved portions configured to cover the portion of the brushes located in the suction head. In particular, the elongated intermediate member may be made to depend from a portion of the housing of the suction head at the location of a concavely curved region on the brush-facing surface of the housing. The elongate intermediate member may be an integral part of the housing or may be provided as a separate component which may be removably coupled to another component of the housing, for example to allow repair or cleaning.

The invention covers other options for achieving a cleaning effect on the surface to be cleaned and possibly the inner surface of the suction head. For example, the suction head may comprise a wetting device configured to be able to supply liquid to at least one area of the surface to be cleaned and/or to at least one area in the suction head. In case the suction head comprises at least one wheel, which is rotatably arranged on the suction head and which is configured to be in contact with the surface to be cleaned, the wetting apparatus may also be configured to be able to supply liquid directly to the at least one wheel. The moistening means may be provided more or less as an additional part of the existing design of the suction head, but it is also possible to provide the moistening means in a more integrated manner. A practical example of a liquid is water or a mixture of water and a detergent. It is practical if the wetting apparatus comprises a catheter system configured to transport a liquid and release the liquid at one or more suitable locations. In the case where the suction head comprises an elongate intermediate member as described above, the duct system may be such that it comprises at least one duct extending through the elongate intermediate member.

In order to facilitate the movement of dirt picked up by the brush from the surface to be cleaned towards the outlet opening in the brush-facing surface of the housing, it is advantageous if a plurality of grooves are provided on the brush-facing surface of the housing, which grooves are designed in particular for this purpose by having the ability to guide dirt particles towards the outlet opening when the brush is rotated.

In the context of the present invention, the brush may be any type of brush suitable for picking up dirt from a surface to be cleaned, wherein the brushes may be chosen to be the same or different brushes. Each brush may be specifically designed to act as an agitator, for example to agitate dirt particles that may be present on the surface. In a practical embodiment of the suction head according to the invention, the at least one brush comprises a core element and a flexible microfibrous element arranged on the core element. In such a brush, a linear mass density below 150g/10km may be applied to the microfibrous element or at least to the end portions thereof, so that the microfibrous element may in fact be highly flexible. The linear mass density as described above may even be lower than 10g/10km, 5g/10km or 1g/10 km. Such microfibrous elements can be placed on the core element in a dense arrangement to interact very effectively with the surface to be cleaned during operation of the suction head. It is furthermore practical if such microfibrous elements are arranged in tufts on the core element.

The invention also relates to a vacuum cleaner, in particular a cordless vacuum cleaner, comprising a suction head as defined and described above, wherein, among other things, the brush-facing surface of the housing comprises two adjacent concavely curved regions, and wherein the outlet opening is dimensioned to cover only a part of the length of the brush.

The above and other aspects of the invention will be apparent from and elucidated with reference to the following detailed description of a practical embodiment of a suction head as defined and described hereinabove.

Drawings

The present invention will now be explained in more detail with reference to the drawings, wherein identical or similar parts are indicated by identical reference numerals, and wherein:

figure 1 schematically shows components of a wet vacuum cleaner and a portion of a floor having a surface to be cleaned according to an embodiment of the invention,

figure 2 schematically shows a bottom view of a suction head according to an embodiment of the invention, which suction head comprises a housing and two brushes, a front brush and a rear brush arranged substantially parallel in the housing,

figures 3 and 4 schematically show cross-sectional views of the suction head taken at different longitudinal positions on the suction head,

fig. 5 schematically shows a longitudinal cross-sectional view of the suction head, taken at a position passing through the centre line of the front brush, with the front brush removed, wherein the viewing direction is from front to back,

fig. 6 schematically shows a longitudinal cross-sectional view of the suction head section with the rear brush removed, taken at a position between the two brushes, wherein the viewing direction is from front to rear,

fig. 7 schematically shows a longitudinal cross-sectional view of the suction head, taken at a position passing through the centre line of the rear brush, with the rear brush removed, wherein the viewing direction is from front to rear,

fig. 8 schematically shows a bottom view of the suction head of fig. 2 with the brush removed,

figure 9 schematically shows a bottom view of the suction head of figure 2 with both the brush and the elongated intermediate member removed, an

Fig. 10 and 11 schematically show a top perspective view of the components of the suction head, wherein part of the housing is shown in a transparent manner.

Detailed Description

Fig. 1 shows a design of a wet vacuum cleaner 100 according to an embodiment of the present invention. The particular vacuum cleaner shown in fig. 1 and described below is only one example of the many vacuum cleaners that are possible within the framework of the invention. It should be noted in this respect that the present invention relates not only to wet vacuum cleaners, but also to other types of vacuum cleaners, such as dry vacuum cleaners having only a dry cleaning function and wet/dry vacuum cleaners having a dry cleaning function in addition to a wet-type cleaning function.

The wet vacuum cleaner 100 is configured 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 operating orientation relative to a surface 10 to be cleaned. The terms with orientation used herein should be understood in relation to the normal operational orientation of the vacuum cleaner 100 with respect to the surface 10 to be cleaned, wherein it is assumed that the surface 10 is in a bottom position and the vacuum cleaner 100 is placed on the surface 10.

During operation of the vacuum cleaner 100, on the side which should face the surface 10, the vacuum cleaner 100 comprises a suction head 101 accommodating two brushes 20, the two brushes 20 being configured to interact with the surface 10 during operation of the vacuum cleaner 100. In the following, it is assumed that each brush 20 is provided in the form of a roller which is rotatable about a rotation axis 21 defined by the central longitudinal axis of the roller, and that each brush 20 comprises a core element 22 and a flexible microfibrous element 23 arranged on the core element 22, which does not alter the fact that other embodiments of the brush 20 are also possible. In the case where the brush 20 comprises flexible microfibrous elements 23, the operating profile of the brush 20 is that of the brush 20 with the flexible microfibrous elements 23 in a fully extended state. The brushes 20 may be identical brushes, but this is not necessary in the context of the present invention. As indicated by the curved arrows depicted in fig. 1 at locations through the brushes 20, the brushes 20 are arranged to be rotatable in opposite directions relative to each other about their respective axes of rotation 21. The suction head 101 includes a housing 30 configured to partially cover the brush 20. The housing 30 may be made of, for example, a plastic material.

In addition to the suction head 101, the vacuum cleaner 100 comprises a main body portion 102, the main body portion 102 being configured to be held by a user of the vacuum cleaner 100. Preferably, the suction head 101 and the body portion 102 are removably coupled to each other. The body portion 102 may be shaped in any suitable manner. The profile of the body portion 102 as shown in fig. 1 is merely illustrative. It is practical if the main body portion 102 includes a handle so that a user can easily grip the main body portion 102 and move the vacuum cleaner 100 over the surface 10 to be cleaned as desired.

In order to drive the brush 20 during operation of the vacuum cleaner 100, the vacuum cleaner 100 is equipped with a suitable electric drive mechanism (not shown). In order to power the drive mechanism and possibly other components of the vacuum cleaner 100, the vacuum cleaner 100 may be connectable to a power source and/or may be equipped with suitable battery means. Preferably, the vacuum cleaner 100 is a cordless device comprising a rechargeable battery means, in which case it may also be practical if the vacuum cleaner 100 is part of a set comprising a charging stand in addition to the vacuum cleaner 100. Such a set may also include a rinse tray, which may be used to clean the brush 20. In the case where the vacuum cleaner 100 is not equipped with a battery, a simple base without charging capability may be provided for receiving and holding the vacuum cleaner 100 when the vacuum cleaner 100 is not in operation.

The main body portion 102 of the vacuum cleaner 100 comprises a reservoir 40 for containing a liquid, such as water or a mixture of water and detergent, and a liquid supply mechanism 41 for supplying the liquid to the wetting apparatus 42 of the suction head 101 during operation of the vacuum cleaner 100. The liquid supply 41 may comprise, for example, any suitable type of pump device, or may be configured to be able to displace liquid as required under the influence of gravity. In the example shown, the wetting device 42 of the suction head 101 is configured to enable a direct supply of liquid to the area of the surface 10 to be cleaned and to the two wheels 90 of the suction head 101, as will be explained in more detail later. Furthermore, in the example shown, the suction head 101 comprises an elongated intermediate part 25, the elongated intermediate part 25 being located in the region 24 between the brushes 20 and comprising two concavely curved portions configured to cover part of the brushes 20, and the moistening device 42 comprises a duct system 43, the duct system 43 being arranged partly in the elongated intermediate part 25 and being configured to convey liquid and to discharge it to a region of the surface 10 and to the two wheels 90. In fig. 1, the reservoir 40, the liquid supply 41 and the wetting device 42 of the suction head 101 are indicated by dashed lines. It is practical if the reservoir 40 is removably coupled to the body portion 102 such that a user can separate the reservoir 40 from the body portion 102 when it is desired to bring the reservoir 40 to a location where the reservoir 40 is filled with liquid.

The main body portion 102 of the vacuum cleaner 100 also includes a dirt reservoir 50 for containing and accumulating wet dirt 11 picked up by the brush 20 from the surface 10 during operation of the vacuum cleaner 100. The dirt reservoir 50 may be configured in a variety of ways conventionally available for accumulating wet dirt picked up from the surface 10 from the incoming dirt 11, such as a cyclone or a tube-in-cup (tube-in-cup) structure. The main body portion 102 comprises a vacuum mechanism 60, the vacuum mechanism 60 being configured to generate a negative pressure for enabling transport of dirt 11 from the area where the brush 20 is located, through the outlet opening 31 in the brush 20 facing surface 32 of the housing 30 and the suction channel 51 extending from the outlet opening 31 to the dirt reservoir 50, to the dirt reservoir 50 in the main body portion 102. As can be seen in particular from the top perspective views of the components of the suction head 101 in fig. 10 and 11, the housing 30 comprises a coupling region 33, the coupling region 33 being configured to enable the housing 30 to be coupled to the suction channel 51, dirt reservoir 50 and vacuum mechanism 60 assembly within the main body portion 102 of the vacuum cleaner 100. The outlet opening 31 is in fluid communication with the coupling area 33.

The basic aspects of the manner of operation of the wet vacuum cleaner 100 are as follows. During operation, the brush 20 is driven in rotation and the liquid supply mechanism 41 is actuated to supply liquid to the wetting device 42 of the suction head 101 so that the liquid can be released to the surface to be cleaned 10 and the two wheels 90. Any dirt that may be present on the area of the surface 10 that can be reached by the brush 20 is separated under the influence of the liquid and the agitation of the brush 20, and dirt particles and dust that may be present on the area of the surface 10 are removed together with the liquid and in the process are conveyed through the outlet opening 31 and the suction channel 51 to the dirt reservoir 50. The dirt 11 is picked up from the surface 10 by the end portions of the microfibrous elements 23 of the brush 20 and, at the point where the end portions no longer contact the surface 10, is thrown off the end portions as the brush 20 rotates.

As shown in fig. 1, the vacuum cleaner 100 may be equipped with a user interface 70, which user interface 70 may include, for example, an on/off button 71. The vacuum cleaner 100 may also include a control system 80, the control system 80 including a microcontroller programmed to move the brush 20 and actuate both the liquid supply 41 and the vacuum 60 in response to inputs received for this purpose from a user via the user interface 70.

Fig. 2 to 11 are used to illustrate aspects of the suction head 101 according to an embodiment of the present invention. In general, the design of the suction head 101 is such that the brush 20 is enclosed as much as possible without hindering the necessary interaction between the brush 20 and the surface 10 to be cleaned, wherein under the influence of a high negative pressure and a high air velocity dirt can be effectively transported towards the outlet opening 31 or further away.

Fig. 2 and 3 show an advantageous design aspect in that the suction head 101 has an elongated intermediate part 25 therein. Advantageously, as shown, the elongate intermediate member 25 depends from a portion of the housing 30 at the location of the concave

curved regions

34, 35 on the surface 32 of the housing 30 facing the brush 20. In any case, the elongated intermediate member 25 functions to close the space 24 between the two brushes 20, so that air entry actually takes place only at the bottom side of the brushes 20. As shown in fig. 2 and 3, the brush 20 fills the entire opening at the bottom side of the suction head 101. This arrangement of the brush 20 is supported not only by the presence of the elongated intermediate member 25, but also by the presence of other constructional details, such as spoilers and edges with cavities, and also side walls of the housing 30 where the surface 32 facing the brush 20 comprises an area 36 covering the end of the brush 20. It is hereby achieved that during operation of the suction head 101 air mainly enters through the brush 20 at the location of its flexible microfibrous elements 23 and at the gap between the encapsulation and the brush 20.

In fig. 3, it can be seen that in the embodiment of the suction head 101 shown, the upper part of the brush 20 is only enclosed for a small distance, such as a distance of about 1mm, for example, for about 75%. As already mentioned, this is advantageous because a narrow gap with a relatively high air speed is achieved, thereby supporting the function of the suction head 101 in finally conveying dirt towards the coupling area 33. The surface of the elongated intermediate member 25 facing the brush 20 is preferably smooth, as opposed to an uneven surface, which also applies to the surface 32 of the housing 30 facing the brush 20, which in the housing part 37 is located at a level substantially at the same level as the elongated intermediate member 25, which level is equal to or lower than the level of the rotation axis 21 of the brush 20. At a further housing part 38, in particular at a higher housing part 38, the surface 32 of the housing 30 facing the brush 20 comprises two adjacent concave

curved areas

34, 35, wherein one concave curved area 34 of the concave

curved areas

34, 35 covers a part of the front brush 20a and wherein the other concave curved area 35 of the concave

curved areas

34, 35 covers a part of the rear brush 20 b. The terms "front" and "rear" are to be understood in relation to the normal position of a user operating the vacuum cleaner 100 including the suction head 101, which is the position on the side of the rear brush 20 b. During operation, the user moves the suction head 101 back and forth with the front brush 20a at the front and the rear brush 20b at the rear.

Preferably, the surface 32 of the housing 30 facing the brush 20 is provided with a plurality of grooves 39 at the location of two adjacent concave

curved areas

34, 35, as best shown in fig. 8 to 11. The grooves 39 are shaped to promote movement of dirt adhering to the brush 20 towards the outlet opening 31 in the surface 32 as the brush 20 rotates. This advantageous effect relies on the following aspects independently of or interacting with each other:

liquid can be delivered through the microfibrous elements of the brush 20. The droplets are ejected from the rotating brush 20 onto the surface 32 of the housing 30 facing the brush 20 and then guided by the groove geometry. The air flow created in the space between the brush 20 and the housing 30 by the rotation of the brush 20 helps to achieve movement of the liquid in the recess 39.

Coarse particles are transported under the influence of the forces caused by the rotation of the brush 20 and guided by the groove geometry.

The small particles are transported through the microfibrous element. Small particles may also be transported by interaction with other particles, creating an airflow in the space between the brush 20 and the housing 30 by the rotation of the brush 20, and interacting with the liquid.

The

housing parts

37, 38 for covering the brush 20 in the close range, in addition to the part of the brush 20 exposed to the surface 10 to be cleaned, functionally constitute one package, but for practical reasons, in particular for manufacturability reasons, may also be provided as separate components joined together during the manufacturing of the suction head 101.

Fig. 4 shows a cross-sectional view of the suction head 101 taken at a position as a center position on the suction head 101 as viewed in the longitudinal direction l, which is a direction in which the rotation axis 21 of the brush 20 extends. At the location of the outlet opening 31, the brush 20 is exposed to a tubular element 27 of the air flow guide member 28, which tubular element opens into the coupling region 33 and is intended to be coupled to the previously mentioned suction channel 51 at the location of the coupling region 33 and to the cuspid 29 of the air flow guide member 28, as will be explained later. A portion of the wall of the tubular element 27 at a location above the outlet opening 31 is oriented non-perpendicular with respect to the upward flow of liquid, dirt and air (as indicated by the arrows in fig. 4) received from the region 24 between the brushes 20. In this way, it is achieved that the flow curves smoothly in the backward direction towards the coupling area 33 and dirt is prevented from depositing on the wall of the tubular element 27.

As explained above, most of the brushes 20 are encapsulated to have a high air velocity, thereby facilitating the transport of dirt through the suction head 101. Another advantageous effect of the high air velocity is that the inner surface of the suction head 101 can be kept clean. In the suction head 101 according to the invention, the outlet opening 31 is dimensioned to cover only a part of the dimension of the brush 20 in the longitudinal direction i, i.e. the length of the brush 20. It should be noted in this respect that in many known suction heads the outlet opening 31 has an extended appearance in the longitudinal direction i to receive dirt along the entire length of the brush 20. A disadvantage of this conventional shape of the outlet opening 31 is that the air velocity is lower and the inner surface is more prone to be oriented perpendicular with respect to the air flow, thus presenting a higher risk of contamination of the inner surface. By narrowing the outlet opening 31 and the tubular element 27, not only is the air velocity increased, but the liquid density in the tubular element is also increased, helping to flush dirt from the tubular element 27. On the other hand, it is practical if the size of the outlet opening 31 and the cross-section of the access tubular element 27 provided by the outlet opening 31 are large enough to achieve an acceptable resistance. Furthermore, as explained, the walls of the tubular elements 27 are preferably not perpendicular (or nearly perpendicular) to the direction of the liquid, dirt and air flow at any location, so that dirt can be prevented from depositing on one or more areas of the walls.

An effective dirt transport of the suction head 101 and a proper function of preventing dirt from depositing on the inner surface can be obtained if the following requirements are met, wherein these requirements should not be understood in any way as being essential to the invention: i) the height of the portion of the front brush 20a exposed to the tubular element 27 through the outlet opening 31 is between 0.3 and 0.5 of the brush diameter, ii) the length of the portion of the front brush 20a exposed to the tubular element 27 through the outlet opening 31 is between 0.8 and 1.3 of the brush diameter, iii) the dimension Q of the portion of the two brushes 20 exposed to the tubular element 27 through the outlet opening 31 is between 0.6 and 1.1 times the distance P between the axes 21 of the brushes 20 in a horizontal direction perpendicular to the longitudinal direction l, iv) a cross-section of the tubular element 27 taken in a vertical direction between the brushes 20 (i.e. at the interface of the concave curved regions 34, 35 in the surface 32 of the housing 30 facing the brushes 20) has an arcuate shape, which may be, for example, circular, or triangular with a domed portion, and v) the angle α between the horizontal direction and the root of the arcuate shape is at least 60 °, wherein a value of about 67.5 ° may be a preferred value effective to prevent deposition of soil on the interior surface. The arcuate cross-section of the tubular member 27 is smoothly connected to the downstream portion of the tubular member 27. Fig. 5 and 7 show the cross-section of the tubular element 27 at other positions and also show the arc-like shape. For the sake of clarity, it should be noted that in both figures, the supporting/driving structure of the brush 20 is shown in cross-section.

Fig. 8 and 9 provide a profile view of the outlet opening 31 as seen from the bottom, i.e. the side on which the brushes 20 are arranged. Fig. 10 and 11 provide views of the air flow guide member 28 intersecting the housing 30, wherein it is noted that the cuspids 29 of the air flow guide member 28 extend all the way to the level of the rotational axis 21 of the brush 20. The cuspids 29 extend on the sides of the tubular element 27, which are opposite sides in a direction perpendicular to the longitudinal direction of the tubular element 27, and down to the level of the rotation axis 21 of the brush 20, at the interface position of the concave

curved zones

34, 35 in the surface 32 of the housing 30 where the outlet opening 31 is present.

The details of the moistening means 42 of the suction head 101 can best be seen in fig. 6. The duct system 43 of the moistening device 42 comprises two

main ducts

44, 45, which are located in different halves of the suction head 101, viewed in the longitudinal direction l, and which can be coupled to the liquid supply 41. Furthermore, the duct system 43 comprises two

branch ducts

46, 47, 48, 49 of each

main duct

44, 45, namely one

branch duct

46, 49 configured to release liquid to the wheel 90 and the

other branch duct

47, 48 configured to release liquid to the area of the surface 10 to be cleaned. The

branch conduits

47, 48 configured to release liquid to the surface to be cleaned 10 are arranged to extend partially through the elongated intermediate member 25, and the liquid supply position where liquid is released to the surface 10 is located at the bottom side of the elongated intermediate member 25, i.e. at the bottom surface portion 26 of the elongated intermediate member 25 configured to face the surface to be cleaned 10.

The wetting apparatus 42 shown here is only one of many examples that are possible in the context of the present invention and may have any desired wetting function, which may include at least one of directly wetting the at least one brush 20 and indirectly wetting the at least one brush 20. When the suction head 101 comprises an elongated intermediate element 25 covering a portion of the brush 20 from the underside of the suction head 101, it may be beneficial to use the elongated intermediate element 25 for accommodating at least a portion of one or more conduits of the conduit system 43 of the moistening device 42, as in the embodiment of the suction head 101 shown, without altering the fact that the invention also covers other options.

It is advantageous if the bottom surface portion 26 of the elongated intermediate member 25 is at a relatively low level, which may be a level of at least 2mm and at most 6mm above the level of the surface 10 to be cleaned when the suction head 101 is in an operative position on the surface 10. Advantageous aspects of having such a small space between the surface to be cleaned 10 and the bottom surface portion 26 of the elongated intermediate member 25 include:

the liquid under the bottom surface portion 26 bridges the surface 10 and cleans the bottom surface portion 26 by surface tension, capturing small dirt particles that may adhere to the bottom surface portion 26.

The cleaning liquid flows from different liquid release positions have a direct cleaning effect on the bottom surface portion 26.

The movement of the suction head 101 causes the area below the bottom surface portion 26 to continuously interact with the brush 20.

It will be clear to a person skilled in the art that the scope of the present disclosure 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 present invention as defined in the attached claims. It is intended that the invention be construed as including all such modifications and alterations insofar as they come within the scope of the appended claims or the equivalents thereof. While the invention has been illustrated and described in detail in the drawings 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 figures are schematic, in which details that are not necessary for understanding the invention have been omitted, and which are not necessarily drawn to scale.

Variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed disclosure, from a study of the drawings, the disclosure, and the appended 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 shall not be construed as limiting the scope of the invention.

Elements and aspects discussed in relation to or in connection with a particular embodiment may be suitably combined with elements and aspects of other embodiments, unless explicitly stated otherwise. 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.

Those skilled in the art will understand that the terms "comprising" and "comprises," as used herein, encompass the term "consisting of … …. Thus, the term "comprising" or "includes" may mean "consisting of" in one embodiment, but may mean "including/having/equipped with at least the species defined and optionally one or more other species" in another embodiment.

Salient aspects of the invention are summarized below. A suction head 101, the suction head 101 being configured for application in a vacuum cleaner 100 and performing a cleaning action on a surface 10 and comprising a housing 30 and two rotatable brushes 20 arranged substantially parallel in the housing 30, a surface 32 of the housing 30 facing the brushes 20 comprising two adjacent concave

curved areas

34, 35, wherein each concave

curved area

34, 35 covers a portion of a respective one of the brushes 20a, 20 b. Furthermore, the surface 32 of the housing 30 facing the brush 20 is provided with an outlet opening 31 in fluid communication with the coupling region 33 of the suction head 101, the outlet opening 31 being located at the interface position of the concavely

curved regions

34, 35 and being dimensioned to cover only a portion of the length of the brush 20.

Claims

1. A suction head (101) configured to be applied in a vacuum cleaner (100) and to perform a cleaning action on a surface (10), the suction head (101) comprising:

a housing (30), the housing (30) comprising a coupling area (33) configured to be able to couple the housing (30) to an air suction source (60) of the vacuum cleaner (100); and

two brushes (20) arranged substantially in parallel in the housing (30), wherein each brush (20) is rotatable around a rotation axis (21) and configured to interact with the surface (10) to be cleaned, and wherein each brush (20) is designed to be able to pick up liquid from the surface (10),

wherein a surface (32) of the housing (30) facing the brush (20) comprises two adjacent concave curved areas (34, 35),

wherein each of the concave curved regions (34, 35) covers a portion of a respective one of the brushes (20a, 20b),

wherein the surface (32) of the housing (30) facing the brush (20) is provided with an outlet opening (31) in fluid communication with the coupling region (33), and

wherein the outlet opening (31) is located at an interface position of the concave curved areas (34, 35) and is dimensioned to cover only a portion of the dimension of the brush (20) in a longitudinal direction (I), which is the direction in which the rotational axis (21) of the brush (20) extends.

2. A suction head (101) according to claim 1, wherein each of the concave curved areas (34, 35) of the surface (32) of the housing (30) facing the brushes (20) follows an operating profile of a portion of a respective one (20a, 20b) of the brushes (20) at a distance of at most 10 mm.

3. A suction head (101) according to claim 2, wherein each of the concave curved areas (34, 35) of the surface (32) of the housing (30) facing the brushes (20) follows the operating profile of a portion of a respective one (20a, 20b) of the brushes (20) at a distance ranging from 0mm to 2 mm.

4. A suction head (101) according to any one of claims 1-3, wherein each of the concavely curved regions (34, 35) of the surface (32) of the housing (30) facing the brushes (20) covers at least a part of a respective one (20a, 20b) of the brushes (20), the at least part being an upper half of the brushes (20a, 20 b).

5. A suction head (101) according to any one of claims 1-4, wherein at least 65% of the dimension of each brush (20) around the respective axis of rotation (21) is covered at a distance in the range of 0mm to 2 mm.

6. A suction head (101) according to any one of claims 1-5, wherein each of the concavely curved regions (34, 35) of the surface (32) of the housing (30) facing the brushes (20) covers one respective one (20a, 20b) of the brushes (20) along the entire dimension of the brush (20) in the longitudinal direction (I).

7. A suction head (101) according to any one of claims 1-6, wherein the operative shape of each brush (20) is substantially cylindrical with a circular periphery, wherein each concave curved region (34, 35) of the housing (30) facing the surface (32) of the brushes (20) covers one respective brush (20a, 20b) of the brushes (20) at the location of a portion of the curved operative contour of the brushes, and wherein the surface (32) of the housing (30) facing the brushes (20) further comprises a region (36) covering an end of the brush (20).

8. Suction head (101) according to any one of claims 1-7, comprising an air flow guiding member (28), the air flow guiding member (28) comprising a tubular element (27), the tubular element (27) being in fluid communication with the outlet opening (31) in the surface (32) of the housing (30) facing the brush (20) and extending towards the coupling area (33).

9. Suction head (101) according to claim 8, wherein the air flow guiding member (28) comprises cuspids (29) at the interface position of the concave curved areas (34, 35) of the surface (32) of the housing (30) facing the brush (20), said cuspids (29) being in fluid communication with the outlet opening (31) in the surface (32) of the housing (30) and extending on the sides of the tubular element (27), said sides being opposite sides in a direction perpendicular to the longitudinal direction (l) of the tubular element (27).

10. A suction head (101) according to claim 8 or 9, wherein a portion of the wall of the tubular element (27) at a position above the outlet openings (31) in the surface (32) of the housing (30) facing the brushes (20) is oriented non-perpendicularly with respect to a flow direction, which is a direction from the surface (10) to be cleaned through the outlet openings (31) and upwards between the brushes (20).

11. A suction head (101) according to claim 10, wherein the portion of the wall of the tubular element (27) is substantially arc-shaped, seen in a cross-section of the tubular element (27), at the interface position of the concave curved areas (34, 35) of the surface (32) of the housing (30) facing the brush (20).

12. A suction head (101) according to any of claims 1-11, comprising an elongated intermediate member (25), the elongated intermediate member (25) being located in a region (24) between the brushes (20) and comprising two concavely curved portions configured to cover portions of the brushes (20).

13. A suction head (101) according to claim 12, wherein the elongated intermediate member (25) is suspended from a portion of the housing (30) of the suction head (101) at a position of the concavely curved region (34, 35) of the surface (32) of the housing (30) facing the brush (20).

14. A suction head (101) according to any of claims 1-13, comprising a wetting device (42), the wetting device (42) being configured to be able to supply liquid to at least one area of the surface (10) to be cleaned and/or to at least one area in the suction head (101).

15. A cordless vacuum cleaner (100) comprising a suction head (101) according to any one of claims 1-14.