Wet cleaning device, method and cleaning assembly comprising the wet cleaning device

Abstract

Provided is a wet cleaning device (100) for removing liquid from a surface. The wet cleaning device comprises a user-moveable portion (102) that is moveable by a user, and an underpressure generator system comprising a resiliently deformable assembly (104, 110). The resiliently deformable assembly is deformable, via the user's movement of the user-moveable portion, to store potential energy. The underpressure generator system is arranged to use the potential energy stored by the deformed resiliently deformable assembly to generate an underpressure for drawing liquid from the surface into the wet cleaning device. The liquid drawn into the wet cleaning device is correspondingly removed from the surface. Further provided is a cleaning assembly comprising a surface cleaning appliance, e.g. a vacuum cleaner, and the wet cleaning device. Additionally provided is a method for removing liquid from a surface using such a wet cleaning device.

Description

[0001] 2024PF00053 18.10.2024

[0002] 1

[0003] WET CLEANING DEVICE, METHOD AND CLEANING ASSEMBLY COMPRISING

[0004] THE WET CLEANING DEVICE

[0005] FIELD OF THE INVENTION

[0006] The invention relates to a wet cleaning device for removing liquid from a surface, and a cleaning assembly comprising a surface cleaning appliance, e.g. a vacuum cleaner, and the wet cleaning device.

[0007] The invention further relates to a method for removing liquid from a surface using such a wet cleaning device.

[0008] BACKGROUND OF THE INVENTION

[0009] Wet cleaning devices, for example wet mopping devices, are known which remove water from a surface being cleaned. Such wet cleaning devices can also apply cleaning liquid, e.g. water, to the surface, and then remove the liquid, e.g. with a suitable cloth.

[0010] Some wet cleaning devices are nowadays equipped with a cleaning liquid delivery system that supplies cleaning liquid, e.g. clean water, towards the surface being cleaned, e.g. by first supplying the cleaning liquid to a cleaner head or nozzle included in the wet cleaning device. Such a cleaning liquid supply may include a manual or electric pump. In this way, the user is relieved of the burden of having to continually return to a bucket to wet a cloth with fresh cleaning liquid.

[0011] Such systems may not, however, include functionality that enables active pickup of liquid from the surface, e.g. floor.

[0012] However, such functionality, in common with the above-mentioned electric pump that may be included in the cleaning liquid supply, may render the wet cleaning device more complicated and costly to manufacture. Electrical components may increase the complexity and cost of the wet cleaning device, particularly in respect of regulatory requirements, such as stipulated by Ingress Protection (IPX) and International Electrotechnical Commission (IEC). These factors may drive up the factory cost price. 2024PF00053 18.10.2024

[0013] 2

[0014] SUMMARY OF THE INVENTION

[0015] The invention is defined by the claims.

[0016] According to examples in accordance with an aspect of the present disclosure, there is provided a wet cleaning device for removing liquid from a surface, the wet cleaning device comprising: a user-moveable portion that is moveable by a user; and an underpressure generator system comprising a resiliently deformable assembly, the resiliently deformable assembly being deformable, via the user’s movement of the user-moveable portion, to store potential energy, the underpressure generator system being arranged to use the potential energy stored by the deformed resiliently deformable assembly to generate an underpressure for drawing liquid from the surface into the wet cleaning device.

[0017] The use of potential energy, stored by deformation of the resiliently deformable assembly via the user’s movement of the user- moveable portion, by the underpressure generator system to generate the underpressure can mean that no electric pump, wiring and / or batteries is / are needed to provide the underpressure. Hence the wet cleaning device can be relatively lightweight and inexpensive to manufacture.

[0018] The resiliently deformable assembly can have any suitable design. The resiliently deformable assembly can include, for example, at least one resilient element, e.g. spring(s), that is deformable to store the potential energy.

[0019] In some embodiments, the underpressure generator system comprises a pump powerable by the potential energy stored by the deformed resiliently deformable assembly. The pump can be of any suitable type, such as a peristaltic pump or a piston pump.

[0020] Alternatively or additionally, the resiliently deformable assembly may comprise a container that is compressible, via the user’s movement of the user-moveable portion, to force fluid out of the container, wherein the container is configured to be resiliently compressible so that the container is urged to expand after being compressed, the container being arranged so that expansion of the container, after being compressed, generates the underpressure in the wet cleaning device for drawing the liquid from the surface into the wet cleaning device.

[0021] The container can provide a relatively straightforwardly manufacturable way of providing the underpressure for removing the liquid from the surface. Since no electric pump, wiring or batteries may be needed to provide the underpressure, the wet cleaning device can be relatively lightweight and inexpensive to manufacture.

[0022] Moreover, removal of the liquid from the surface by the wet cleaning device assists in making the surface dryer after the wet cleaning device has been used to clean the 2024PF00053 18.10.2024

[0023] 3 surface. Removal of dirty liquid from the surface can also assist to keep the wet cleaning device clean during use, so as to reduce the need for rinsing, as well as minimizing spread of dirt over the surface (in embodiments in which the wet cleaning device is moveable across the surface).

[0024] The wet cleaning device may comprise a dirt inlet structure arranged to receive the liquid from the surface when the underpressure is generated, e.g. by expansion of the container. To this end, the dirt inlet structure may be fluidly connected to the container.

[0025] The dirt inlet structure may, for example, be arranged at a bottom side of the wet cleaning device, which bottom side faces, in use, the surface from which the liquid is to be removed.

[0026] The dirt inlet structure, e.g. the dirt inlet structure arranged at the bottom side of the wet cleaning device, may be covered by a porous material whose pores carry the liquid away from the surface to the dirt inlet structure. The porous material can assist to maintain the underpressure in the wet cleaning device due to the wet porous material creating an air seal due to surface tension of the liquid, e.g. water, over the pores of the wet porous material.

[0027] In some embodiments, the user-moveable portion is arranged to be moveable by the user’s foot, when the wet cleaning device is orientated for use on a floor. This can provide a relatively convenient way of providing the underpressure, since the user’s hands can be free to perform other functions / tasks, such as holding a handle for moving the wet cleaning device across the floor.

[0028] The user-moveable portion can be provided in any suitable manner. In some embodiments, the user-moveable portion is provided by a pedal and / or by a wall portion that at least partly delimits the container. Such a pedal can be arranged to cause compressing of the container when the pedal is moved by the user’s foot.

[0029] In some embodiments, the wet cleaning device comprises a resilient element, e.g. a spring, configured to deform from an initial state when the container is compressed, with resilience of the resilient element causing the deformed resilient element to revert towards the initial state to urge expansion of the container to generate the underpressure.

[0030] As an alternative or in addition to the resilient element, a container wall of the container may be resiliently deformable, with the container wall being deformable from an initial shape to allow the container to be compressed. In such embodiments, resilience of the container wall may cause the deformed container wall to revert towards the initial shape and thereby urge expansion of the container to generate the underpressure. 2024PF00053 18.10.2024

[0031] 4

[0032] The wet cleaning device may comprise a one-way valve configured to enable the fluid, e.g. air, in the container to be forced, through the one-way valve, out of the wet cleaning device when the container is compressed.

[0033] The wet cleaning device may comprise a dirty liquid collection volume for receiving the liquid removed from the surface. The dirty liquid collection volume may be at least partly provided in the container and / or in a further container that is fluidly coupled to the container.

[0034] In some embodiments, the wet cleaning device comprises an attachment assembly for attaching the wet cleaning device to, and / or detaching the wet cleaning device from, a surface cleaning appliance. The surface cleaning appliance may, for example, be a vacuum cleaner.

[0035] The attachment assembly may, for instance, be configured to attach the wet cleaning device to a cleaner head, e.g. nozzle, of the surface cleaning appliance.

[0036] In some embodiments, the wet cleaning device comprises a cleaning liquid delivery assembly for delivering cleaning liquid towards the surface. The cleaning liquid delivery assembly can have any suitable design. For example, the cleaning liquid delivery assembly may be arranged to deliver the cleaning liquid via the user’s movement of the usermoveable portion or via the user’s movement of a further user- moveable portion included in the wet cleaning device.

[0037] In embodiments in which the porous material is included in the wet cleaning device, the user’s movement of the user-moveable portion, e.g. the user’s pushing of the pedal, may cause the cleaning liquid to be delivered to the porous material.

[0038] This (pre-)wetting of the porous material can assist the porous material to more quickly create the air seal provided by surface tension of the liquid over the pores of the porous material.

[0039] It is noted that in embodiments in which the porous material is included in the wet cleaning device, the underpressure generator system may be configured so that the underpressure is low enough to avoid breaking air seals provided due to surface tension of the liquid over the pores of the porous material.

[0040] More generally, the underpressure generator system may be configured to provide a pressure difference between the inside of the wet cleaning device and atmospheric pressure for drawing liquid into the wet cleaning device, e.g. via the porous material, with the pressure difference being in a range of 3000 Pa to 13500 Pa, preferably 5000 Pa to 9000 Pa, most preferably 7000 Pa to 9000 Pa. 2024PF00053 18.10.2024

[0041] 5

[0042] According to examples in accordance with another aspect of the present disclosure, there is provided a cleaning assembly comprising: a surface cleaning appliance; and the wet cleaning device according to any of the embodiments described herein.

[0043] In some embodiments, the surface cleaning appliance is a vacuum cleaner. Alternatively or additionally, the surface cleaning appliance comprises a cleaner head for moving across the surface from which the liquid is to be removed, with the wet cleaning device being attached or attachable to the cleaner head.

[0044] According to examples in accordance with a further aspect of the present disclosure, there is provided a method for removing liquid from a surface using a wet cleaning device that has a user- moveable portion moveable by a user, and an underpressure generator system comprising a resiliently deformable assembly deformable via the user’s movement of the user-moveable portion, the method comprising moving the user-moveable portion to deform the resiliently deformable assembly and thereby store potential energy, the underpressure generator system being arranged to use the potential energy stored by the deformed resiliently deformable assembly to generate an underpressure in the wet cleaning device that draws the liquid from the surface into the wet cleaning device.

[0045] In some embodiments, the resiliently deformable assembly comprises a container compressible via the user’s movement of the user- moveable portion, with the method comprising moving the user-moveable portion to compress the container, wherein the container is configured to be resiliently compressible so that the container is urged to expand after being compressed, the container being arranged so that expansion of the container, after being compressed, generates the underpressure in the wet cleaning device that draws the liquid from the surface into the wet cleaning device.

[0046] The wet cleaning device used in the method may be the wet cleaning device according to any of the embodiments described herein.

[0047] These and other aspects of the invention will be apparent from and elucidated with reference to the embodiment(s) described hereinafter.

[0048] BRIEF DESCRIPTION OF THE DRAWINGS

[0049] For a better understanding of the invention, and to show more clearly how it may be carried into effect, reference will now be made, by way of example only, to the accompanying drawings, in which:

[0050] FIG. 1 provides a schematic cross-sectional view of a wet cleaning device according to an example; 2024PF00053 18.10.2024

[0051] 6

[0052] FIGs. 2A to 2E depict removal of liquid from a surface using the wet cleaning device shown in FIG. 1; and

[0053] FIG. 3 schematically depicts a cleaning assembly comprising a wet cleaning device according to an example.

[0054] DETAILED DESCRIPTION OF THE EMBODIMENTS

[0055] The invention will be described with reference to the Figures.

[0056] It should be understood that the detailed description and specific examples, while indicating exemplary embodiments of the apparatus, systems and methods, are intended for purposes of illustration only and are not intended to limit the scope of the invention. These and other features, aspects, and advantages of the apparatus, systems and methods of the present invention will become better understood from the following description, appended claims, and accompanying drawings. It should be understood that the Figures are merely schematic and are not drawn to scale. It should also be understood that the same reference numerals are used throughout the Figures to indicate the same or similar parts.

[0057] Provided is a wet cleaning device for removing liquid from a surface. The wet cleaning device comprises a user-moveable portion that is moveable by a user, and an underpressure generator system comprising a resiliently deformable assembly. The resiliently deformable assembly is deformable, via the user’s movement of the user-moveable portion, to store potential energy. The underpressure generator system is arranged to use the potential energy stored by the deformed resiliently deformable assembly to generate an underpressure for drawing liquid from the surface into the wet cleaning device.

[0058] For example, the resiliently deformable assembly can include a container that is compressible, via the user’s movement of the user-moveable portion, to force fluid out of the container. The container is configured to be resiliently compressible so that the container is urged to expand after being compressed, to generate the underpressure in the wet cleaning device for drawing the liquid from the surface into the wet cleaning device. The liquid drawn into the wet cleaning device is correspondingly removed from the surface.

[0059] Further provided is a cleaning assembly comprising a surface cleaning appliance, e.g. a vacuum cleaner, and the wet cleaning device. Additionally provided is a method for removing liquid from a surface using such a wet cleaning device. 2024PF00053 18.10.2024

[0060] 7

[0061] FIG. 1 schematically depicts a wet cleaning device 100 according to an example. The wet cleaning device 100 is for removing liquid from a surface, for example a surface of a floor, wall, window, and so on.

[0062] The wet cleaning device 100 may be moveable across the surface during removal of the liquid from the surface, so that liquid can be removed by the wet cleaning device 100 from different regions of the surface.

[0063] The wet cleaning device 100 comprises a user- moveable portion 102 that is moveable by a user, and an underpressure generator system comprising a resiliently deformable assembly 104, 110. The resiliently deformable assembly 104, 110 is deformable, via the user’s movement of the user-moveable portion, to store potential energy, and the underpressure generator system is arranged to use the potential energy stored by the deformed resiliently deformable assembly 104, 110 to generate an underpressure for drawing liquid from the surface into the wet cleaning device 100.

[0064] The use of potential energy, stored by deformation of the resiliently deformable assembly 104, 110 via the user’s movement of the user-moveable portion 102, by the underpressure generator system to generate the underpressure can mean that no electric pump, wiring and / or batteries is / are needed to provide the underpressure. Hence the wet cleaning device 100 can be relatively lightweight and inexpensive to manufacture.

[0065] The resiliently deformable assembly 104, 110 can have any suitable design. The resiliently deformable assembly 104, 110 can include, for example, at least one resilient element 110, e.g. spring(s), that is deformable to store the potential energy.

[0066] In some embodiments, the underpressure generator system comprises a pump powerable by the potential energy stored by the deformed resiliently deformable assembly 104, 110. The pump can be of any suitable type, such as a peristaltic pump or a piston pump.

[0067] Alternatively or additionally, the resiliently deformable assembly 104, 110 may comprise a container 104 that is compressible, via the user’s movement of the usermoveable portion 102, to force fluid, e.g. air, out of the container 104. The container 104 may be configured to be resiliently compressible so that the container 104 is urged to expand after being compressed.

[0068] The container 104 may be arranged so that expansion of the container 104, after being compressed via the user’s movement of the user-moveable portion 102, generates an underpressure in the wet cleaning device 100 for drawing the liquid from the surface into the wet cleaning device 100. The liquid drawn into the wet cleaning device 100 is correspondingly removed from the surface. 2024PF00053 18.10.2024

[0069] 8

[0070] The resilient compressibility of the container 104 can be regarded as putting a pre-tension on the user- moveable portion 102 and the container 104 to create the underpressure in the wet cleaning device 100, when the user-moveable portion 102 is released by the user after movement of the user- moveable portion 102 to compress the container 104.

[0071] The container 104 can provide a relatively straightforwardly manufacturable way of providing the underpressure for removing the liquid from the surface. Since no electric pump, wiring or batteries may be needed to provide the underpressure, the wet cleaning device 100 can be relatively lightweight and inexpensive to manufacture.

[0072] Moreover, removal of the liquid from the surface by the wet cleaning device 100 assists in making the surface dryer after the wet cleaning device 100 has been used to clean the surface. Removal of dirty liquid from the surface can also assist to keep the wet cleaning device 100 clean during use, so as to reduce the need for rinsing, as well as minimizing spread of dirt over the surface (in embodiments in which the wet cleaning device 100 is moveable across the surface).

[0073] In order for the underpressure to be generated, the user is required to move the user-moveable portion 102 to cause deformation of the resiliently deformable assembly 104, 110, e.g. to cause compression of the container 104. For example, the user may move, e.g. press, the user-moveable portion 102 at the start of each cleaning session using the wet cleaning device 100.

[0074] In some embodiments, and referring to FIGs. 2B and 2C, the user- moveable portion 102 is arranged to be moveable by the user’s foot 105, when the wet cleaning device 100 is orientated for use on a floor. This can provide a relatively convenient way of providing the underpressure, since the user’s hands can be free to perform other functions / tasks, such as holding a handle for moving the wet cleaning device 100 across the floor.

[0075] The user-moveable portion 102 can be provided in any suitable manner. In some embodiments, the user-moveable portion 102 is provided by a pedal and / or by a wall portion that at least partly delimits the container 104. As best shown in FIGs. 1, 2B and 2C, such a pedal can be arranged to cause compressing of the container 104 when the pedal is moved by the user’s foot 105.

[0076] The wet cleaning device 100 may comprise a dirt inlet structure 106 arranged to receive the liquid from the surface when the underpressure is generated, e.g. by expansion of the container 104. To this end, the dirt inlet structure 106 may be fluidly connected to the container 104. 2024PF00053 18.10.2024

[0077] 9

[0078] The dirt inlet structure 106 may, for example, be arranged at a bottom side of the wet cleaning device 100, which bottom side faces, in use, the surface.

[0079] The dirt inlet structure 106, e.g. the dirt inlet structure arranged at the bottom side of the wet cleaning device 100, may be covered by a porous material 108 whose pores carry the liquid away from the surface to the dirt inlet structure 106.

[0080] When the porous material 108 is dry, the porous material 108 may be regarded as being in an “air transport state” in which air is transported through each of the dry pores of the porous material 108. A “liquid transport state” corresponds to liquid, e.g. water, being transported through the (wetted) pores of the porous material 108. When there is no longer a feed of liquid to the pores, a “fluid block state” may be adopted. The “fluid block state” corresponds to the state at which the surface tension of the (residual) liquid retained in the wetted pores of the porous material 108 prevents fluid transport through the pores. In the latter state, a surface or barrier is created at the boundary between air and liquid, e.g. water. This barrier can assist to maintain the underpressure, e.g. the underpressure provided by the expansion of the container 104, for instance when no flow or only relatively low flow is being generated by the expansion of the container 104.

[0081] In other words, the porous material 108 can assist to maintain the underpressure in the wet cleaning device 100 due to the wet porous material 108 creating an air seal due to surface tension of the liquid, e.g. water, over the pores of the wet porous material 108.

[0082] Whenever a droplet of liquid, e.g. water, is added to the porous material 108, the air-liquid surface disappears and suddenly the function of transporting the liquid can be fulfilled. Liquid, e.g. water, may only be transported at the position where it is fed to the porous material 108. Once no liquid is provided for transportation, the wet porous material 108 can return to its “fluid block state.”

[0083] Pore size and geometry of the porous material 108 may be selected to provide a relatively high surface tension of the liquid, e.g. water, over the pores of the porous material 108, while also providing sufficiently low transport pressure of the liquid through the porous material 108. The porous material 108 may be wettable by the liquid, e.g. water, on the surface so that the liquid is able to seal the porous material 108 from air (noting that ingress of air may lead to premature cessation of liquid removal by the wet cleaning device 100).

[0084] In some embodiments, the porous material 108 is formed from a polyester and / or a polyamide. The wettability properties of polyester and polyamide, e.g. nylon, 2024PF00053 18.10.2024

[0085] 10 particularly following plasma treatment, can make such fibers especially suitable for picking up aqueous liquid from the surface.

[0086] Alternatively or additionally, the porous material 108 may comprise one or more of a woven fabric, e.g. a microfiber woven fabric, a mesh, and a perforate membrane.

[0087] It is noted that the better-defined pore geometry of the mesh or perforate membrane can mean that the pores of the porous material 108 can be larger, and hence less susceptible to clogging, while still enabling a relatively high underpressure to be provided.

[0088] In embodiments in which the porous material 108 comprises a fabric, e.g. a woven fabric, the porous material 108 can be regarded as a dirty liquid extraction fabric, through which the liquid is removed from the surface and is air- sealed when wetted.

[0089] The dirt inlet structure 106 can have any suitable design. In some embodiments, such as shown in FIGs. 1 and 2A to 2E, the dirt inlet structure 106 comprises a chamber arranged above the porous material 108.

[0090] The dirt inlet structure 106, e.g. the chamber, can be arranged so that the underpressure is applied over an area, e.g. the whole area, of the porous material 108.

[0091] In some embodiments, such as shown in FIG. 3, the wet cleaning device 100 comprises a cleaning liquid delivery assembly 109 for delivering cleaning liquid towards the surface. The cleaning liquid delivery assembly 109 can have any suitable design. For example, the cleaning liquid delivery assembly 109 may be arranged to deliver the cleaning liquid via the user’s movement of the user-moveable portion 102 or via the user’s movement of a further user-moveable portion included in the wet cleaning device 100.

[0092] Movement of the user-moveable portion 102, e.g. pedal, or the further usermoveable portion, e.g. a (further) pedal, may create a temporarily higher pressure in a cleaning liquid tank included in the cleaning liquid delivery assembly 109, which higher pressure forces the cleaning liquid towards the surface.

[0093] In embodiments in which the porous material 108 is included in the wet cleaning device 100, the user’s movement of the user-moveable portion 102, e.g. the user’s pushing of the pedal, may cause the cleaning liquid to be delivered to the porous material 108.

[0094] This (pre-)wetting of the porous material 108 can assist the porous material 108 to more quickly create the air seal provided by surface tension of the liquid over the pores of the porous material 108.

[0095] In other embodiments, the cleaning liquid delivery assembly 109 includes an electric pump for pumping the cleaning liquid towards the surface. Alternatively, the cleaning 2024PF00053 18.10.2024

[0096] 11 liquid delivery system can make use of diffusion, a dripping principle, e.g. at least partly driven by gravity, etc.

[0097] It is noted that the cleaning liquid delivery assembly 109 can be omitted from the wet cleaning device 100, such that the wet cleaning device 100 only has liquid removal functionality. The latter can, for example, be applicable when the wet cleaning device 100 is in the form of a window cleaning device.

[0098] In some embodiments, the wet cleaning device 100 comprises a cleaning material for contacting the surface. The cleaning material can, for example, be arranged to apply the cleaning liquid delivered from the cleaning liquid delivery assembly 109 to the surface. Alternatively or additionally, the cleaning material can be detachable from the wet cleaning device 100.

[0099] Detachment of the cleaning material, e.g. mop-cloth, can facilitate cleaning and / or replacement of the cleaning material after use.

[0100] In some embodiments, the cleaning material is detachable from the porous material 108. In other embodiments, the porous material 108 is included in the cleaning material. For example, the cleaning material, e.g. the detachable cleaning material, and the porous material 108 may be provided by a single cloth. Such a single cloth may, for instance, be used for applying the cleaning liquid to the surface as well as for, when wetted, assisting to maintain the underpressure in the wet cleaning device 100.

[0101] In some embodiments, and referring to FIGs. 1 and 2A to 2E, the wet cleaning device 100 comprises a resilient element 110, e.g. a spring, configured to deform from an initial state when the container 104 is compressed, with resilience of the resilient element 110 causing the deformed resilient element 110 to revert towards the initial state to urge expansion of the container 104 to generate the underpressure.

[0102] In embodiments in which the resilient element(s) 110 is / are spring(s), the spring(s) can be of any suitable type. For example, the spring can be a helical compression spring, a helical extension spring, a torsion spring, a conical spring or a spiral spring.

[0103] An advantage associated with a conical spring is that such a conical spring may be relatively flat when compressed (see, e.g., FIG. 2C).

[0104] More generally, the resilient element 110, e.g. the spring, can be selected based on spring constant, spring force, cost and dimensions.

[0105] As an alternative or in addition to the resilient element 110, a container wall of the container 104 may be resiliently deformable, with the container wall being deformable from an initial shape to allow the container 104 to be compressed. In such embodiments, 2024PF00053 18.10.2024

[0106] 12 resilience of the container wall may cause the deformed container wall to revert towards the initial shape, and thereby urge expansion of the container 104 to generate the underpressure.

[0107] More generally, the container 104 can have any suitable design provided that the container 104 is capable of being compressed and then, due to its resilient configuration, being expanded to provide the underpressure. In some embodiments, such as shown in FIGs. 1 and 2A to 2E, the container 104 is provided by a bellows.

[0108] Such a bellows may, for example, comprise a concertinaed wall that enables the container 104 to be compressed and to expand following being compressed.

[0109] In embodiments in which the wet cleaning device 100 comprises the pedal and the bellows, the user may push down on the pedal with their foot 105 in order to compress the bellows.

[0110] The container’s 104 volume, e.g. the volume inside the bellows, may be selected to be larger than the expected volume of liquid to be drawn into the wet cleaning device 100 during a cleaning session using the wet cleaning device 100. For example, the container’s 104 volume may be equal to the expected volume of liquid to be drawn into the wet cleaning device 100 during the cleaning session plus a volume for generating the underpressure, e.g. considering compressibility of the container’s 104 volume and other air volume(s) in the wet cleaning device 100.

[0111] Only a relatively small volume of fluid, e.g. air, may be displaced at the start of the cleaning session to generate the underpressure for the total liquid intake. This may enable the wet cleaning device 100 to have a relatively simple and compact design which, for example, requires only a single movement of the user-moveable portion 102, e.g. push of the pedal, at the start of the cleaning session.

[0112] The resilient element 110 (if present) and the container 104 can have any suitable design and dimensions provided that the user is able to exert sufficient force to cause compression of the container 104 via the user’s movement of the user-moveable portion 102, and that a desired underpressure level is achievable during expansion of the container 104. The force required to be exerted by the user, e.g. on the pedal, to cause compression of the container 104 may be sufficiently low to be convenient to the user.

[0113] In some embodiments, the shape of the bellows, or more generally the shape of the container 104, can be designed to compensate for force-displacement non-linearity of the resilient element 110, e.g. the spring.

[0114] More generally, the wet cleaning device 100 may comprise a dirty liquid collection volume 112 for receiving the liquid removed from the surface. The dirty liquid 2024PF00053 18.10.2024

[0115] 13 collection volume 112 may be at least partly provided in the container 104 and / or in a further container 114 that is fluidly coupled to the container 104, e.g. via a tube 115.

[0116] In some embodiments, the further container 114 is fluidly connected to the container 104, e.g. bellows, via the tube 115, and also fluidly connected to the dirt inlet structure 106 above the porous material 108.

[0117] The dirty liquid collection volume 112 may be in the range of 100 mL to 500 mL, such as 100 mL to 300 mL, e.g. about 200 mL.

[0118] In embodiments in which the wet cleaning device 100 comprises the bellows and the further container 114, the tube 115 may connect the bellows with the further container 114 in which the dirty liquid collection volume 112 is provided. The underpressure can, for example, be provided in the container 104, the further container 114, and the dirt inlet structure 106, e.g. chamber, above the porous material 108.

[0119] In other embodiments, the further container 114 may be omitted, with the dirty liquid collection volume 112 being provided in the container 104. For example, the interior of the bellows could serve as the dirty liquid collection volume 112.

[0120] The wet cleaning device 100 may include a cap or plug (not visible) that is moveable to allow the liquid received in the dirty liquid collection volume 112 to be emptied after use.

[0121] In relatively simple embodiments, the pedal, the resilient element 110, e.g. spring, and the further container 114 can be omitted. In such embodiments, the resilience of the container wall, e.g. the bellows, provides the pre-tension. For example, pre-tension of the bellows may be selected so that the requisite underpressure is provided following the user releasing the user-moveable portion 102 in the form of the wall portion of the container 104.

[0122] In a non-limiting example, the bellows is directly compressed by the user’s foot 105, rather than there being a pedal.

[0123] The wet cleaning device 100 may comprise a one-way valve 116 configured to enable the fluid, e.g. air, in the container 104 to be forced, through the one-way valve 116, out of the wet cleaning device 100 when the container 104 is compressed. In other words, the fluid, e.g. air, can escape through the one-way valve 116 when the container 104, e.g. the bellows, is compressed.

[0124] The one-way valve 116 can be arranged in any suitable manner. In embodiments in which the wet cleaning device 100 comprises the further container 114, the one-way valve 116 can be arranged in a wall of the further container 114, as shown in FIGs. 1 and 2 A to 2E. 2024PF00053 18.10.2024

[0125] 14

[0126] In some embodiments, such as shown in FIGs. 2A to 2E, a (further) one-way valve 117, is provided between the dirt inlet structure 106 and the further container 114. The (further) one-way valve 117 may restrict backflow of the liquid received in the further container 114 back towards the dirt inlet structure 106.

[0127] It is generally noted that the resilient element 110, e.g. spring, and / or the resiliently deformable container wall can be regarded as putting a pre-tension on the usermoveable portion 102 and the container 104 to create the underpressure in the wet cleaning device 100, when the user-moveable portion 102, e.g. pedal, is released by the user after movement of the user-moveable portion 102 to compress the container 104.

[0128] In embodiments in which the porous material 108 is included in the wet cleaning device 100, a minimum spring force of the resilient element 110, e.g. spring, and / or the resiliently deformable container wall may be selected so that the underpressure created in the wet cleaning device 100 is high enough for the liquid to be transported through the porous material 108. For example, the underpressure may be at least 3000 Pa, e.g. at least 4000 Pa.

[0129] A maximum spring force of the resilient element 110, e.g. spring, and / or the resiliently deformable container wall may be selected so that the underpressure created in the wet cleaning device 100 is sufficiently low to avoid breaking of the air seals (provided due to surface tension of the liquid, e.g. water, over the pores of the porous material 108), so as to minimize or prevent intake of air that could otherwise prematurely stop removal of the liquid from the surface. For example, the underpressure may be at most 13500 Pa, e.g. at most 9000 Pa or at most 6000 Pa.

[0130] Such an underpressure may be maintained during the whole cleaning session, to remove a total volume of liquid that can be expected during the cleaning session.

[0131] A spring constant of the resilient element 110, e.g. spring, and / or the resiliently deformable container wall may be selected such that in a range from compression to total release of the user- moveable portion 102 by the user, the spring force causes the above-mentioned underpressure-defined maximum and minimum values to be fulfilled.

[0132] More generally, the underpressure generator system may be configured to provide a pressure difference between the inside of the wet cleaning device 100 and atmospheric pressure for drawing liquid into the wet cleaning device 100, e.g. via the porous material 108, with the pressure difference being in a range of 3000 Pa to 13500 Pa, preferably 5000 Pa to 9000 Pa, most preferably 7000 Pa to 9000 Pa.

[0133] The pressure difference can be directly and positively verified in a given wet cleaning device 100 by, for example, drilling a hole in a tube of the wet cleaning device 100 2024PF00053 18.10.2024

[0134] 15 which is fluidly connected with the dirt inlet structure 106 and using the hole to couple to a pneumatic pressure sensor itself having a tube with a membrane covering an end thereof; the sensor being thus connected using an airtight connection. The sensor may be arranged to avoid disturbing the flow, hence the skilled person will arrange the sensor to avoid, for instance, creating a bypass flow. No flow may be towards or from the sensor: only pressure is transmitted. In this way, the flow of the appliance may never be compromised (hence may remain at the set level in spite of the sensor installation).

[0135] In embodiments in which the porous material 108 is included, the pressure sensor is connected between the porous material 108 and the underpressure generator system and as close to the porous material 108 as possible, to minimise the influence of other factors, such as flow resistance etc., on the sensed pressure difference.

[0136] The sensing element / membrane of the pressure sensor / gauge is ideally arranged / positioned in the pressure sensor so that the sensing element can be placed directly (without the requirement for connecting tubes) in the tube, or in a cavity behind the porous material 108.

[0137] By positioning the membrane of the pressure sensor, in other words membrane pressure gauge, with the membrane positioned at, in other words in line with, the wall of the tube (or exposed to the cavity), measurement errors may be minimized, as will be appreciated by a person skilled in the art.

[0138] It is noted that air bubbles inside narrow tubes may generate resistance (capillary / surface tension effects), and hence may influence the measurement. Hence the skilled person will further appreciate that care is also to be taken that air bubbles (water-air surfaces) do not unduly influence the pressure difference measurement.

[0139] It is further noted that a column of water present between the pressure sensor and the porous material 108 should be deducted from the measurement result (if such a column of water is present during the measurement), to compensate for the static pressure generated by the column of water.

[0140] Once the pressure sensor is arranged as described above, it may be ascertained that maintenance of the underpressure is due to the porous material 108 and not some other element, such as a valve. Any such element that influences the underpressure that is presented to the porous material 108 should be rendered inoperable for the purpose of performing the measurement.

[0141] Component(s) that dispense the cleaning liquid is / are disengaged when performing the pressure difference measurement. 2024PF00053 18.10.2024

[0142] 16

[0143] The user moves the user- moveable portion 102, and recording of data from the pressure sensor is started.

[0144] The pick-up area of the wet cleaning device 100 is suspended in a layer of water, at max. 5 mm depth.

[0145] The pick-up area is then lifted from the water without tilting it in any way (so that the wet cleaning device 100 remains in a cleaning position, as if it were positioned to clean the floor), e.g. so that the water is no longer touching the porous material 108 (at this point, “free water” will be removed from the porous material 108, all pores will go into their “blocked state”, and the breaking pressure is determinable. An equilibrium is established in an “end regime” in which the applied flow results in an underpressure which causes no more fluid blocks to break).

[0146] In the context of embodiments including the porous material 108, the breaking pressure obtained from the “end regime” is the “pressure difference between the inside of the wet cleaning device 100 and atmospheric pressure for drawing liquid into the wet cleaning device 100 ” It is verified from the measurement result whether or not the 3000 Pa to 13500 Pa range (or the 5000 Pa to 9000 Pa range or the 7000 Pa to 9000 Pa range, if applicable) is satisfied.

[0147] It is noted that the porous material 108 may be arranged to contact liquid on the surface. Thus, the porous material 108 may be defined from a front side of the porous material 108 exposable to liquid on the surface to a back side exposed to the dirt inlet structure 106.

[0148] FIGs. 2A to 2E are for illustrating operation of the wet cleaning device 100 shown in FIG. 1. FIG. 2A shows a starting condition of the wet cleaning device 100, with the container 104, in this case bellows, expanded, and the further container 114 being empty.

[0149] FIG. 2B shows the user-moveable portion 102 being moved by the user, in this case by the user’s foot 105 moving the pedal, to compress the container 104 (see arrow Al in FIG. 2B). This causes fluid in the form of air to be forced out of the container 104 and released from the wet cleaning device 100 via the one-way valve 116 (see arrow A2 in FIG. 2B). In FIG. 2C, the container 104 is fully compressed, e.g. with all air being forced out of the container 104.

[0150] In FIG. 2D, the user-moveable portion 102 is released by the user, e.g. when the user starts to mop the surface using the wet cleaning device 100. The resilient element 110, e.g. spring, forces the user-moveable portion 102 back towards its starting position (see arrow A3 in FIG. 2D), and expands the container 104, which results in the underpressure 2024PF00053 18.10.2024

[0151] 17 being generated in the wet cleaning device 100, and the liquid 118 being drawn from the surface into the wet cleaning device 100 (see arrows A4 in FIG. 2D). In this non-limiting example, the underpressure is generated in the container 104 and in the further container 114. The underpressure causes the one-way valve 116 to close, and the liquid 118 to be drawn through the porous material 108 and into the further container 114, via the (further) one-way valve 117 (see arrow A5 in FIG. 2D).

[0152] FIG. 2E shows cessation of removal of the liquid 118 from the surface. When the surface is dry and no liquid is being added to the porous material 108, the surface tension of the liquid 118 over the pores of the porous material 108 can provide a counter force (see arrows A6 in FIG. 2E) which prevents the user-moveable portion 102, e.g. pedal, from further moving towards its initial position (see arrow A7) and the container 104, e.g. bellows, from further expanding. In this way, the volume of the container 104, e.g. bellows, is effectively only used to displace / draw in the liquid 118 from the surface.

[0153] When the surface is wetted again with the liquid 118, the liquid 118 may be added to the porous material 108, with disappearance of the air-liquid surface, and concomitant cancelling out of the surface tension, causing the container 104 to be further expanded to draw in the added liquid 118. This can take place until, at the end of the cleaning session, the total volume of liquid is picked up from the surface.

[0154] As briefly mentioned above, the underpressure can be provided by a single movement of the user-moveable portion 102, e.g. a single press of the pedal. However, it can also be contemplated that the user is required to move the user-moveable portion 102 multiple times during the cleaning session. In such embodiments, the volume of the container 104 can be reduced and the stroke or force required to compress the container 104 can be made smaller.

[0155] In some embodiments, multiple movements of the user- moveable portion 102, e.g. multiple pushes of the pedal, can be made at the start of the cleaning session to provide the underpressure. In such embodiments, the resilient element 110, e.g. spring, may be increasingly loaded by such multiple movements. This may necessitate a lock-mechanism for locking each successive position at which the resilient element 110 is further loaded.

[0156] In some embodiments, the wet cleaning device 100 comprises an air buffer tank for maintaining the underpressure during intake of the liquid. In such embodiments, the spring force may just ensure that the container 104 is expanded after being compressed, with it being the air buffer tank that controls the underpressure level. 2024PF00053 18.10.2024

[0157] 18

[0158] In embodiments in which a single movement of the user-moveable portion 102 is implemented at the start of the cleaning session, compression of the container 104 causes ejection of a total fluid, e.g. air, volume that is equal to the volume of liquid to be removed from the surface, e.g. about 0.2 liters, plus the required volume to reach the desired underpressure level in the air buffer tank, container 104, and further container 114 (if present). During intake of the liquid, the underpressure may decrease, but to ensure that the underpressure stays at or above a minimum level for drawing the liquid into the wet cleaning device 100 and at or below a maximum level, e.g. to avoid breaking of the air seals due to surface tension of the liquid over the pores of the porous material 108, the air buffer tank may need to have a relatively large volume, such as about 0.7 liters.

[0159] In embodiments in which multiple movements of the user-moveable portion 102 are implemented at the start of the cleaning session, the volume of the container 104 can be made smaller, but the container 104 may itself require a first air valve for releasing air to the atmosphere, and the container’s 104 volume may be separated from the volume of the air buffer tank by a second air valve. In this case, compression of the container 104 causes air to escape via the first air valve, and expansion of the container 104 causes displacement of air from the air buffer tank into the container 104 via the second air valve. The container 104 can be compressed again to create additional underpressure.

[0160] In embodiments in which multiple movements of the user-moveable portion 102 are implemented during the cleaning session, the volumes of the container 104 and the air buffer tank can be reduced.

[0161] Use of the air buffer tank rather than the resilient element 110, e.g. spring, to maintain the underpressure can thus necessitate a relatively large volume of the air buffer tank or multiple movements of the user-moveable portion 102 during the cleaning session.

[0162] In some embodiments, such as shown in FIG. 3, the wet cleaning device 100 comprises an attachment assembly 120 for attaching the wet cleaning device 100 to, and / or detaching the wet cleaning device 100 from, a surface cleaning appliance 122. The surface cleaning appliance 122 may, for example, be a vacuum cleaner.

[0163] The attachment assembly 120 may, for example, attach the wet cleaning device 100 to a cleaner head 124, e.g. nozzle, of the surface cleaning appliance 122.

[0164] The user grasping a handle 126 included in the surface cleaning appliance 122 may move the cleaner head 124, together with the wet cleaning device 100 attached thereto, across the surface. 2024PF00053 18.10.2024

[0165] 19

[0166] In more general terms, the present disclosure contemplates providing the wet cleaning device 100 to the user together with the surface cleaning appliance 122. A cleaning assembly 100, 122 according to the present disclosure correspondingly comprises the surface cleaning appliance 122, and the wet cleaning device 100 according to any of the embodiments described herein.

[0167] In embodiments in which the surface cleaning appliance 122 is a vacuum cleaner, the surface cleaning appliance 122 can provide vacuuming dust pick-up functionality (see arrow Bl in FIG. 3), as well as liquid removal via the wet cleaning device 100 (see arrow B2 in FIG. 3). When the wet cleaning device 100 includes the cleaning liquid delivery assembly 109, the wet cleaning device 100 may also deliver the cleaning liquid towards the surface (see arrow B3 in FIG. 3).

[0168] In embodiments in which the wet cleaning device 100 is attachable to, and detachable from, the surface cleaning appliance 122, the wet cleaning device 100 can be attached to the surface cleaning appliance when the liquid removal functionality is to be used, and detached from the surface cleaning appliance 122 when no such liquid removal functionality is needed and / or to facilitate storage of the surface cleaning appliance 122 and the wet cleaning device 100 after use.

[0169] In other embodiments, the wet cleaning device 100 may be permanently fixed to the surface cleaning appliance 122, e.g. to the cleaner head 124 thereof. For example, the wet cleaning device 100 may be permanently fixed to a vacuum cleaner’s nozzle.

[0170] It is emphasized that owing to deformation of the resiliently deformable assembly 104, 110, e.g. expansion of the container 104. providing the underpressure, the wet cleaning device 100 can be regarded as being standalone, in the sense that no connection to a tube, hinge, suction channel, power supply or any other part of a surface cleaning appliance 122, e.g. vacuum cleaner, may be required in order for the liquid removal functionality to be used.

[0171] Moreover, the wet cleaning device 100 may be relatively robust, since the wet cleaning device 100 may not include valve(s) contactable by the liquid removed from the surface.

[0172] It is noted that the vacuum cleaner may be a mains operated vacuum cleaner or a battery operated vacuum cleaner. The vacuum cleaner, e.g. mains or battery operated vacuum cleaner, may be a household vacuum cleaner or a commercial / industrial vacuum cleaner. 2024PF00053 18.10.2024

[0173] 20

[0174] In some embodiments, the wet cleaning device 100 is a standalone wet cleaning device 100, which need not be attached to a surface cleaning appliance 122. In such embodiments, the wet cleaning device 100 may, for example, include a handle for enabling the user to move the wet cleaning device 100 across a floor.

[0175] In such embodiments, the handle may provide the user- moveable portion 102, rather than the pedal. For example, the user may push, e.g. vertically on and / or to pivot, the handle to deform the resiliently deformable assembly 104, 110.

[0176] For instance, the user may push, e.g. vertically on and / or to pivot, the handle to compress the container 104.

[0177] In more general terms, the wet cleaning device 100 may be a mopping device, for example a household mopping device or a commercial / industrial mopping device. Such a mopping device can, for example, be an electric mopping device, e.g. owing to having a cleaning liquid delivery assembly 109 that comprises an electric pump.

[0178] It is also reiterated that in some embodiments the wet cleaning device 100 is in the form of a window cleaning device.

[0179] The present disclosure further provides a method for removing liquid from a surface using a wet cleaning device 100 that has a user-moveable portion 102 moveable by a user, and an underpressure generator system comprising a resiliently deformable assembly 104, 110 deformable via the user’s movement of the user-moveable portion 102. The method comprises moving the user-moveable portion to deform the resiliently deformable assembly 104, 110 and thereby store potential energy, with the underpressure generator system being arranged to use the potential energy stored by the deformed resiliently deformable assembly 104, 110 to generate an underpressure in the wet cleaning device 100 that draws the liquid from the surface into the wet cleaning device 100.

[0180] In some embodiments, the resiliently deformable assembly 104, 110 comprises a container 104 compressible via the user’s movement of the user-moveable portion 102.

[0181] More generally, the wet cleaning device 100 can be according to any of the embodiments described herein.

[0182] In embodiments in which the container 104 is included in the resiliently deformable assembly 104, 110, the method may comprise moving the user-moveable portion 102 to compress the container 104, with the container 104 being configured to be resiliently compressible so that the container is urged to expand after being compressed. The container 104 may be arranged so that expansion of the container 104, after being compressed, 2024PF00053 18.10.2024

[0183] 21 generates the underpressure in the wet cleaning device 100 that draws the liquid from the surface into the wet cleaning device 100.

[0184] Variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed invention, from a study of the drawings, the disclosure and the appended claims. In the claims, the word "comprising" does not exclude other elements or steps, and the indefinite article "a" or "an" does not exclude a plurality.

[0185] 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.

[0186] If the term "adapted to" is used in the claims or description, it is noted the term "adapted to" is intended to be equivalent to the term "configured to".

[0187] Any reference signs in the claims should not be construed as limiting the scope.

Claims

2024PF00053 18.10.202422CLAIMS:

1. A wet cleaning device (100) for removing liquid from a surface, the wet cleaning device comprising: a user-moveable portion (102) that is moveable by a user; and an underpressure generator system comprising a resiliently deformable assembly (104, 110), the resiliently deformable assembly being deformable, via the user’s movement of the user-moveable portion, to store potential energy, the underpressure generator system being arranged to use the potential energy stored by the deformed resiliently deformable assembly to generate an underpressure for drawing liquid from the surface into the wet cleaning device.

2. The wet cleaning device (100) according to claim 1, wherein the resiliently deformable assembly comprises a container (104) that is compressible, via the user’s movement of the user-moveable portion (102), to force fluid out of the container, wherein the container is configured to be resiliently compressible so that the container is urged to expand after being compressed, the container being arranged so that expansion of the container, after being compressed, generates an underpressure in the wet cleaning device for drawing the liquid from the surface into the wet cleaning device.

3. The wet cleaning device (100) according to claim 2, wherein the resiliently deformable assembly (104, 110) comprises a resilient element (110) configured to deform from an initial state when the container (104) is compressed, the resilient element being configured to, following being deformed, revert towards the initial state to urge expansion of the container; optionally wherein the resilient element comprises a spring.

4. The wet cleaning device (100) according to claim 2 or claim 3, wherein a container wall of the container (104) is resiliently deformable, the container wall being deformable from an initial shape to allow the container to be compressed, the container wall being configured to, following being deformed, revert towards the initial shape, and thereby urge expansion of the container.2024PF00053 18.10.2024235. The wet cleaning device (100) according to any one of claims 2 to 4, comprising a one-way valve (116) configured to enable the fluid from the container (104) to be forced, through the one-way valve, out of the wet cleaning device when the container is compressed.

6. The wet cleaning device (100) according to any one of claims 1 to 5, comprising a dirt inlet structure (106) arranged to receive the liquid from the surface when the underpressure is generated, the dirt inlet structure being covered by a porous material (108) whose pores carry the liquid away from the surface to the dirt inlet structure.

7. The wet cleaning device (100) according to claim 6, wherein the underpressure generator system is configured so that the underpressure is low enough to avoid breaking air seals provided due to surface tension of the liquid over the pores of the porous material (108).

8. The wet cleaning device (100) according to any one of claims 1 to 7, wherein the underpressure generator system is configured to provide a pressure difference between the inside of the wet cleaning device and atmospheric pressure for drawing liquid into the wet cleaning device, with the pressure difference being in a range of 3000 Pa to 13500 Pa, preferably 5000 Pa to 9000 Pa, most preferably 7000 Pa to 9000 Pa.

9. The wet cleaning device (100) according to any one of claims 1 to 8, wherein the underpressure generator system comprises a pump powerable by the potential energy stored by the deformed resiliently deformable assembly; optionally wherein the pump is a peristaltic pump or a piston pump.

10. The wet cleaning device (100) according to any one of claims 1 to 9, wherein the user-moveable portion (102) is arranged to be moveable by the user’s foot, when the wet cleaning device is orientated for use on a floor.

11. The wet cleaning device (100) according to any one of claims 1 to 10, comprising a dirty liquid collection volume (112) for receiving the liquid removed from the surface.2024PF00053 18.10.20242412. The wet cleaning device (100) according to claim 11 when dependent from any one of claims 2 to 5, wherein the dirty liquid collection volume (112) is at least partly provided in the container (104) and / or in a further container (114) that is fluidly coupled to the container.

13. The wet cleaning device (100) according to any one of claims 1 to 12, comprising an attachment assembly (120) for attaching the wet cleaning device to, and / or detaching the wet cleaning device from, a surface cleaning appliance (122).

14. The wet cleaning device (100) according to any one of claims 1 to 13, comprising a cleaning liquid delivery assembly (109) for delivering cleaning liquid towards the surface.

15. A cleaning assembly (100, 122) comprising: a surface cleaning appliance (122); and the wet cleaning device (100) according to any one of claims 1 to 14; optionally wherein the surface cleaning appliance is a vacuum cleaner.

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