A cleaner head for an appliance

Abstract

Provided is a cleaner head (10) for an appliance. The cleaner head comprises a roller (14) for contacting a surface to be cleaned and a drive component (80) for driving motion of the roller (14). A portion of the drive component is located within the roller. The cleaner head also comprises a heat pipe (30) comprising an evaporator end (31) thermally coupled to the portion, and a condenser end (32) opposite to the evaporator end.

Description

[0001] A CLEANER HEAD FOR AN APPLIANCE

[0002] Field of the Invention

[0003] The present invention relates to a cleaner head for an appliance, and to an appliance comprising such a cleaner head.

[0004] Background of the Invention

[0005] Appliances for cleaning or treating surfaces may comprise a cleaner head that is in contact with the surface to be cleaned or treated in use. Some appliances utilise liquids, such as water, to clean or treat a surface. Such liquids may be utilised alongside a roller, mop, wipe, or other component for applying a wiping force to the surface.

[0006] Summary of the Invention

[0007] According to a first aspect of the present invention there is provided a cleaner head for an appliance, the cleaner head comprising: a roller for contacting a surface to be cleaned; a drive component for driving motion of the roller, wherein a portion of the drive component is located within the roller; and a heat pipe comprising an evaporator end thermally coupled to the portion, and a condenser end opposite to the evaporator end.

[0008] Providing the heat pipe may be beneficial for transferring heat away from the portion of the drive component, which is located within the roller and so may be otherwise difficult to access. Heat pipes typically comprise a heat exchange fluid, which changes phase to transfer heat between the evaporator end and the condenser end. In particular, the heat exchange fluid may be caused to evaporate at the evaporator end due to heating from the portion of the drive component, and then condensed at the condenser end which may be at a lower temperature than the evaporator end and / or the drive component, in use. In this way, the heat exchange fluid may absorb heat as latent heat at the evaporator end and release the latent heat at the condenser end. This may provide improved heat transfer along the heat pipe compared, for example, to a thermally conductive metal strip.

[0009] Providing the portion of the drive component within the roller may better utilise available space in the cleaner head. This may allow a size of the cleaner head to be reduced, and / or provide more space for other components in the cleaner head. Optionally, the drive component is entirely located within the roller, which may provide a compact arrangement.

[0010] Optionally, the condenser end is located external to the roller. This may improve an accessibility of the condenser end for cooling the condenser end. This may also ensure that heat generated by the drive component is efficiently removed from the roller. Optionally, the condenser end is not coupled to the portion of the drive component, or to any part of the drive component, except via the evaporator end. This may allow the condenser end to be at a lower temperature than the evaporator end and / or the portion of the drive component, which may improve the level of heat passed from the drive component along the heat pipe from the evaporator end to the condenser end.

[0011] Optionally, the condenser end is located within a housing of the cleaner head, such as within or external to the roller. This may improve a safety of the cleaner head by reducing a likelihood of contact, by a user, with the condenser end, which may be at an elevated temperature relative to an atmosphere surrounding the housing. Optionally, the condenser end is located partly, or entirely, external to the housing of the cleaner head. This may provide further physical separation between the evaporator end and the condenser end, which may improve a thermal efficiency of the heat pipe. Optionally, the cleaner head comprises a cooling member for transferring heat between the condenser end and a cooling source, the cooling member thermally coupled to the condenser end.

[0012] The cooling member may be thermally coupled between the condenser end and the cooling source, and / or the cooling member may place the condenser end in direct thermal contact with the cooling source. The cooling source may comprise a cooling fluid, such as an ambient atmosphere within or external to a housing of the cleaner head, and / or liquid from a liquid distribution tank of the cleaner head. Alternatively, or in addition, the cooling source may comprise a housing of the cleaner head, which may be at a lower temperature than the condenser end, in use.

[0013] Optionally, the cleaner head comprises a barrier thermally separating the condenser end and / or the cooling member from other components, such as electronic circuitry, in the cleaner head. This may reduce a likelihood of overheating of such other components.

[0014] Optionally, the cooling member is located entirely external to the roller. Optionally, the cooling member is located at an external end of the roller, which may provide a compact arrangement of components in the cleaner head. The end of the roller may be an end at which the roller is mounted in the cleaner head. Alternatively, the cooling member may be located away from the roller, such as in a different part of the cleaner head, which may improve heat transfer away from the roller and drive component located therein.

[0015] Optionally, the cooling member is located at least partly within the roller. Optionally, the cooling member is located entirely within the roller. Optionally, the cooling member is located partly or wholly at an internal end of the roller. The end of the roller may be an end at which the roller is mounted in the cleaner head. Locating the cooling member partly or entirely within the roller may provide a compact arrangement of components in the cleaner head. This may reduce a size of the cleaner head and / or provide space for other components in the cleaner head.

[0016] Optionally, the cooling member is located partly, or entirely, external to a housing of the cleaner head comprising the roller. In this way, the cooling source may comprise air external to the housing. Locating the cooling member partly or entirely external to the housing may reduce heating of an atmosphere inside the housing by the cooling member, in use. This may lead to greater thermal efficiency of the cooling member. Locating the cooling member partly or entirely external to the housing may also provide further physical separation between the evaporator end of the heat pipe and the cooling member, which may improve a thermal efficiency of the heat pipe.

[0017] Optionally, the cooling member is located entirely within a housing of the cleaner head comprising the roller. The cooling source may comprise air internal to the housing. Locating the cooling member within the housing of the cleaner head may improve a safety of the cleaner head by reducing a likelihood of contact, by a user, with the cooling member, which may be at a temperature greater than an atmosphere surrounding the cleaner head.

[0018] Optionally, the cooling member is located in, and / or thermally coupled to, the liquid distribution tank, where provided. In this way, the cooling source may comprise liquid stored in the liquid distribution tank. The liquid stored in the liquid distribution tank may have a higher heat capacity than an atmosphere within and / or external to the cleaner head, and so may provide improve cooling of the condenser end and thus the drive component.

[0019] Optionally, the cooling member comprises a heat sink thermally coupled to the condenser end of the heat pipe. In this way, the heat sink may conduct heat between the condenser end and the cooling source, where provided. The heat sink may provide a simple arrangement for effectively conducting heat between the condenser end and the cooling source. The heat sink may comprise a disc or annulus of thermally conductive material, such as copper. A central axis of the disc or annulus, which passes through a centre point on a circular surface of the disc, or through a centre point of a circular aperture defined by the annulus, may be parallel and / or coincident with an axis of rotation of the roller. Such a discshaped or annular heat sink may better conform to a geometry of the cleaner head and / or a housing thereof. This may reduce an amount of space required for the heat sink and / or provide a compact arrangement of components in the cleaner head. For instance, a mounting member for mounting the roller and / or the drive component in a housing of the cleaner head may pass through the annulus, and / or the disc may conform to an end portion which abuts the roller, in use.

[0020] Optionally, the cleaner head comprises a thermally conductive cooling member layer located between and contacting both the condenser end and the cooling member. The thermally conductive cooling member layer may comprise a thermal pad or thermal paste. The thermally conductive cooling member layer may improve an efficiency of heat transfer between the condenser end and the cooling member. Alternatively, the condenser end and cooling member may be in direct contact.

[0021] Optionally, the cleaner head comprises a thermally conductive drive component layer located between and contacting both the evaporator end and the portion of the drive component located within the roller. In a similar way to the thermally conductive cooling member layer, the thermally conductive drive component layer may comprise a thermal pad or thermal paste. The thermally conductive drive component layer may improve an efficiency of heat transfer between the drive component and the evaporator end. Optionally, the heat sink comprises one or more thermally conductive fins. The fin or fins may increase a surface area of the heat sink. This may allow the heat sink to transfer heat more effectively between the condenser end and the cooling source, such as air or liquid in the liquid distribution tank, surrounding the heat sink. This may provide more efficient passive cooling of the drive component.

[0022] Optionally, the cooling source comprises a cooling fluid, and the heat sink comprises a passage through which the cooling fluid is flowable. In other words, the passage may be configured to receive the cooling fluid. In this way, the heat sink may provide active cooling of the drive component. Such active cooling may be more efficient than passive cooling, particularly where the cooling fluid is a liquid, such as water, which has a higher specific heat capacity than air. As noted above, the cooling fluid may be air or may be liquid from the liquid distribution tank.

[0023] Optionally, the heat sink comprises a thermally conductive pipe defining the passage. In this way, the heat sink may transfer heat between the condenser end and the cooling fluid flowing through the thermally conductive pipe, in use. The thermally conductive pipe may comprise a copper pipe, or tube, thermally coupled to the condenser end. The thermally conductive pipe may comprise one or more loops thermally coupled to the condenser end. Providing the one or more loops may increase a surface area of the heat sink in contact with the condenser end, which may improve a heat transfer capacity of the heat sink.

[0024] Optionally, the heat sink comprises a block of thermally conductive material. Optionally, the passage is defined through the block of thermally conductive material. The block of thermally conductive material may provide a structure which improves an ease of mounting the heat sink in the cleaner head. The block may also provide a larger surface area than, for instance, a pipe, which may improve heat exchange between the block and a surrounding atmosphere. Optionally, the block is polyhedral, such as pyramidal, prismatic, cuboidal, spherical, or any other suitable polyhedral shape. The block may, at least in part, conform to a geometry of the cleaner head and / or the roller. This may provide a compact arrangement in the cleaner head. For instance, the block may comprise a curved surface conforming to a curvature of the roller, or a curvature of a housing surrounding the roller. The thermally conductive material may comprise a metal, such as copper, which may improve a heat capacity of the block.

[0025] Optionally, when the heat sink comprises one or more fins, the fin or fins may protrude from the block. This may increase a surface area of the heat sink, which may allow the heat sink to transfer heat more effectively between the condenser end and the cooling fluid, such as air, surrounding the heat sink. In this way, the heat sink may provide more efficient passive and / or active cooling of the drive component.

[0026] The passage may be defined on a surface of the block. Alternatively, the passage may be defined through the block. The passage may be a circuitous flow path through the block. This may improve a heat capacity of the heat sink, by increasing a surface area inside the passage. Alternatively, the passage may be a straight flow path through the block, such as defined by a hole through the block. Optionally, the hole passes from one side of the block to an opposite side of the block.

[0027] Optionally, the cleaner head comprises a flow disturber for disturbing a flow of the cooling fluid through the passage. The flow disturber may be arranged upstream of and / or within the passage. The flow disturber may impart a swirl and / or a turbulence into the flow of the cooling fluid through the passage. Providing the flow disturber may increase an efficiency of heat transfer between the heat sink and the cooling fluid. In particular, the flow disturber may comprise a helical insert, such as a coil, disposed in a flow path through the passage or upstream of the passage to impart a swirl into the flow of cooling fluid through the flow path.

[0028] Optionally, the cooling member comprises a manifold, the manifold comprising a chamber in which the condenser end is located. Optionally, the cooling source is a cooling fluid, and the cooling fluid is passable through the chamber to contact the condenser end.

[0029] By placing the condenser end in contact with the cooling fluid, a rate of heat transfer between the condenser end and the cooling fluid may be improved. Increasing a size of a portion of the condenser end in the chamber may improve the rate of heat transfer between the condenser end and the liquid.

[0030] Optionally, the manifold is located partially, or wholly, within the housing and / or the roller. Providing the manifold at least partly within the housing and / or the roller may provide a compact arrangement of components. Optionally, the manifold is located entirely external to the roller and / or the housing of the cleaner head. Providing a manifold external to the roller and / or the housing may improve an ease of access to the manifold, such as for servicing. This may also further physically distance the condenser end from the portion of the drive component, which may improve a thermal efficiency of the heat pipe.

[0031] Optionally, the manifold comprises an inlet through which the cooling fluid is receivable into the manifold, and an outlet through which the cooling fluid is expellable from the manifold, and the chamber is fluidically coupled between the inlet and the outlet.

[0032] In this way, the cooling fluid, such as liquid from the liquid distribution tank, where provided, may be receivable in the inlet, passable through the chamber, and expellable through the outlet, such as towards the roller. This may provide a simple and thermally efficient arrangement for passing the cooling fluid through the chamber in contact with the condenser end.

[0033] Optionally, the inlet and the outlet are located on the same side of the manifold. This may provide a compact arrangement in the cleaner head. Alternatively, the inlet and the outlet may be located on different (e.g., opposite or adjacent) sides of the manifold. This may ensure that fluid leaving the condenser end towards the outlet travels in a different direction to fluid entering the chamber. This may, in turn, provide a better distribution of heat within the manifold, such as by reducing hotspots due to recirculating flow in the manifold. Optionally, the inlet may be located on a side of the manifold beside and facing the condenser end.

[0034] Optionally, the manifold is located at an end of the roller, such as outside the roller or partly or wholly inside the roller. Optionally, the condenser end extends externally from the roller into the manifold. Locating the manifold at the end of the roller and / or providing the condenser end in the chamber of the manifold may provide a compact arrangement of components in the cleaner head, thereby reducing a size of the cleaner head and / or providing space for other components in the cleaner head, such as a larger liquid distribution tank.

[0035] Optionally, the manifold comprises a flow guide defining a flow path through the chamber, wherein the condenser end is located in the flow path. The flow guide may reduce hotspots in the chamber by improving a continuity of flow through the chamber and across the condenser end of the heat pipe.

[0036] Optionally, the chamber comprises an inlet compartment through which the cooling fluid is flowable from the inlet to the condenser end, and an outlet compartment through which the cooling fluid is flowable from the condenser end to the outlet. Optionally, the flow guide at least partly delimits the inlet compartment and the outlet compartment. In this way, the flow guide may reduce or prevent undesirable heating of cooling fluid in the inlet compartment by cooling fluid in the outlet compartment. This may, in turn, allow cooler fluid to be provided to the condenser end, thereby improving thermal efficiency.

[0037] Optionally, the cleaner head comprises a seal for sealing the condenser end in the chamber. The seal may be a rubber seal. The seal may prevent leakage of water from manifold. This may be particularly advantageous where the manifold is located in proximity to electronic components of the cleaner head, such as PCB boards.

[0038] Optionally, the cleaner head comprises a liquid distribution tank for storing liquid to be distributed to the roller, and wherein the cooling source comprises liquid from the liquid distribution tank. In other words, the cooling fluid, where provided, may comprise liquid from the liquid distribution tank. In other words, the liquid in the liquid distribution tank may be used to cool the condenser end, and therefore the portion of the drive component. This may better utilise an available source of cooling fluid in the cleaner head, while providing active cooling of the portion of the drive component.

[0039] Optionally, the cleaner head comprises a flow path through which liquid in the liquid distribution tank is passable from the liquid distribution tank to the cooling member. Optionally, the flow path is configured to pass fluid from the liquid distribution tank to the roller via the cooling member. This may make efficient use of the cooling fluid, as it is passed to the roller, to cool the condenser end of the heat pipe.

[0040] Optionally, the flow path comprises the passage, where provided. Optionally, the flow path comprises a conduit. For example, the conduit may include one or more liquid tubes. Optionally, the conduit is fluidically coupled between the liquid distribution tank and the passage, where provided. In this way, liquid may be received in, and passed through, the passage from the conduit. In such an example, the liquid may be in direct contact with a wall of the passage, such as a wall defined by the pipe or by the block of thermally conductive material. This may improve heat transfer between the liquid and the heat sink, where provided. Optionally, the conduit is formed of a different material from the cooling member, such as a flexible material, such as silicone.

[0041] Optionally, the conduit passes through the passage so that, in use, the conduit defines an interface between a wall of the passage and liquid in the conduit. This may provide a simple construction, such as without requiring connectors between the conduit and the passage.

[0042] Optionally, the conduit is fluidically connected to the manifold, where provided. Optionally, the conduit comprises the chamber in the manifold.

[0043] The flow path and / or conduit may serve a dual-purpose of distributing liquid from the liquid distribution tank to the roller and cooling the drive component via the heat sink and heat pipe.

[0044] Optionally, the cleaner head comprises a filter arranged in the flow path between the liquid distribution tank and the cooling member. The filter may be arranged within the conduit. The filter may be arranged to remove contaminants from liquid that is passed through the flow path, such as through the conduit and / or the passage, from the liquid distribution tank. This may reduce a likelihood of clogging in the conduit and / or passage. This may also provide a cleaner fluid to the roller, which may improve an effectiveness of the cleaner head to clean the surface. Optionally, the filter may be arranged in an outlet pipe within the liquid distribution tank, where, in use, liquid exits the liquid distribution tank through the outlet pipe.

[0045] Optionally, the cleaner head comprises a housing and a mounting member for rotatably mounting the roller in the housing. Optionally, the heat pipe extends towards the mounting member from the portion of the drive component. This may provide a more efficient arrangement for transferring heat away from the drive component. The cooling member may be coupled to the mounting member, such as by being mounted on the mounting member, which may provide a compact arrangement of components in the cleaner head.

[0046] Optionally, the cleaner head comprises a housing and a drive component mount for mounting the drive component in the housing. Optionally, the heat pipe extends towards the drive component mount from the portion of the drive component. Optionally, the mounting member, where provided, and drive component mount are located on the same side of the cleaner head, and / or may be a part of the same component.

[0047] Optionally, the roller extends across at least 80% of the width of the housing. Optionally, the roller extends across at least 90% of the width of the housing, for instance across substantially the entirety of a width of the housing. This may ensure that the roller provides a relatively large surface area with which to contact the surface to be cleaned for a given width of cleaner head. This may also ensure the housing is no wider than it needs to be to accommodate the roller, which may result in a cleaner head that is easier to handle and / or that can fit in tighter spaces to clean such spaces. The housing may comprise a pair of opposing side walls, and the roller may extend across at least 80%, or at least 90%, of the width of the housing between the pair of opposing side walls.

[0048] This may provide a balanced weight distribution for the cleaner head. Optionally, the cleaner head comprises a pump for pumping liquid from the liquid distribution tank, such as through the conduit, where provided. Optionally, the pump is located adjacent the liquid distribution tank across the width of the housing. In this way, dimensions of the housing other than the width, for example such as the height and / or the depth of the housing, may be minimised in comparison to an arrangement where the pump and the liquid distribution tank are offset from one another across the width of the housing. Minimising a height of the housing may be desirable to maintain a relatively low height profile of the cleaner head, thereby enabling the cleaner head to be placed underneath objects such as furniture, in use.

[0049] Optionally, the cleaner head comprises a liquid collection tank for collecting liquid from the surface to be cleaned. Optionally, the liquid collection tank is located intermediate the roller and the liquid distribution tank. Locating the liquid collection tank between the roller and the liquid distribution tank may, in comparison to an arrangement where the liquid collection tank is located above the liquid distribution tank or vice versa, provide a relatively low height profile for the cleaner head. This may facilitate placing of the cleaner head underneath objects, such as furniture, in use.

[0050] Optionally, the cleaner head comprises an attachment mechanism for releasably attaching the cleaner head to an appliance.

[0051] This may allow the cleaner head to be easily removed from the appliance, such as to allow the liquid distribution tank to be refilled more easily and / or to allow the liquid collection tank, where provided, to be emptied more easily. Providing a cleaner head that is releasably attachable to an appliance may also improve an ease of maintenance of the cleaner head, such as for cleaning the roller or replacing components.

[0052] The attachment mechanism may be located on an external surface of the housing at a position intermediate the liquid distribution tank and the roller. This may provide a balanced arrangement for the cleaner head, which may provide improved manoeuvrability of the cleaner head for a user when compared to, for example, an arrangement where the roller and the liquid distribution tank are located on the same side of the attachment mechanism. The attachment mechanism may be substantially centrally located on the external surface of the housing.

[0053] A second aspect of the present invention provides an appliance comprising the cleaner head of the first aspect.

[0054] Optionally, the appliance comprises a main unit, wherein the cleaner head is releasably attachable to the main unit. This may enable the functionality of the cleaner head to be selectively provided for the appliance, for example enabling the cleaner head to be swapped for a further cleaner head of different form and / or functionality.

[0055] Optionally, the main unit comprises a power supply for supplying electrical power to the drive component. This may reduce the need for a separate power supply to be provided in the cleaner head, which may reduce size and / or weight and / or cost of the cleaner head.

[0056] It will be appreciated that the appliance may comprise and / or benefit from any of the optional features of, and advantages ascribed to, the cleaner head of the first aspect.

[0057] A third aspect of the present invention provides a cleaner head for an appliance, the cleaner head comprising: a liquid distribution tank for storing liquid to be distributed to a surface to be cleaned; a roller for contacting the surface to be cleaned; a flow path through which the liquid is passable from the liquid distribution tank to the roller; a drive component for driving one or more of: motion of the roller; and distribution of liquid through the flow path; and a heat pipe comprising an evaporator end thermally coupled to the drive component and a condenser end thermally coupled to the flow path. It will be appreciated that the cleaner head of the third aspect may comprise and / or benefit from any of the optional features and / or advantages of the first aspect. For instance, a portion of the drive component may be located within the roller. The appliance of the second aspect may comprise the cleaner head of the third aspect.

[0058] Brief Description of the Drawings

[0059] Figure 1 is a perspective view of a cleaner head;

[0060] Figure 2 is a perspective view of a first housing portion of the cleaner head of Figure 1 ;

[0061] Figure 3 is a perspective view of a second housing portion of the cleaner head of Figure 1 ;

[0062] Figure 4 is a schematic view of the cleaner head of Figure 1 with an upper wall and a side wall of its housing removed;

[0063] Figure 5 is a schematic illustration of an appliance comprising the cleaner head of Figure 1 ;

[0064] Figure 6 is a schematic illustration of the roller 14, when viewed along an axis of the roller 14;

[0065] Figure 7 is a schematic illustration through the cleaner head of Figure 1 showing a heat pipe and cooling member;

[0066] Figures 8a to 8e are schematic illustrations of a first construction of the cooling member of Figure 7; Figure 9 is a schematic illustration of a second construction of the cooling member of Figure 7;

[0067] Figure 10 is a schematic illustration of a third construction of the cooling member of Figure 7;

[0068] Figure 11 is a schematic diagram of the cleaner head of Figure 1 showing a flow path for passing liquid to the cooling member of Figure 7;

[0069] Figure 12 is a schematic illustration of a fourth construction of the cooling member of Figure 7;

[0070] Figures 13 and 14 are schematic illustrations of a fifth construction of the cooling member of Figure 7; and

[0071] Figures 15a to 15c are schematic illustrations of a sixth construction of the cooling member of Figure 7.

[0072] Detailed Description of the Invention

[0073] A cleaner head 10 is illustrated in Figure 1.

[0074] The cleaner head 10 comprises a housing 12, a roller 14, and an attachment mechanism 16. The roller 14 is rotatably connected to the housing 12 such that it rotates about a rotational axis R (see Figure 2) that is substantially parallel to a width direction W of the housing 12. The housing 12 comprises a first housing portion 18 and a second housing portion 20 releasably connected to each other.

[0075] The first housing portion 18 is illustrated in Figure 2, and comprises a right side wall 22, a tank assembly 24, and a right-side mounting member 26. The right side wall 22 is generally elongate in form, and extends generally in a depth direction D of the cleaner head 10. The tank assembly 24 and the right-side mounting member 26 are each fixedly connected to the right side wall 22 (allowing the right- side mounting member 26 to be fixedly connected to the tank assembly 24). The tank assembly 24 and the right-side mounting member 26 extend from the right side wall 22 such that the tank assembly 24 and the right-side mounting member 26 are located within the housing 12 when the cleaner head 10 is assembled.

[0076] The right-side mounting member 26 is located at a front end 32 of the right side wall 22, with the tank assembly 24 located rearwardly of the right-side mounting member 26 in the depth direction D. The front end 32 of the right side wall 22 is generally shaped to correspond to the curvature of the roller 14, and has a region of reduced radius such that the roller 14 is partially exposed at the front of the housing 12 when the cleaner head 10 is assembled and the roller 14 contacts the surface to be cleaned.

[0077] The tank assembly 24 comprises a liquid distribution tank 34 for storing liquid to be distributed to a surface to be cleaned and a liquid collection tank 36 for collecting liquid from the surface to be cleaned. The liquid collection tank 36 and the liquid distribution tank 34 are fixedly connected to one another. The liquid distribution tank 34 is hollow in form and comprises an inlet 42 and a closure 44. The inlet 42 is covered and closed by the closure 44, and has the form of an aperture defined by a neck with an external screw thread that cooperates with an internal screw thread of the closure 44. The inlet 42 is located on the liquid distribution tank 34 such that the inlet 42 is located within an interior volume of the housing 12 when the cleaner head 10 is assembled. The inlet 42 faces in the width direction W along the housing 12 of the cleaner head 10. This width direction W is a direction toward a sidewall of the housing 12 when the cleaner head 10 is located on a surface to be cleaned in use.

[0078] The closure 44 has the form of a cap that covers the inlet 42, and is removable from the inlet 42 via twisting. The closure 44 comprises a valve member 46 that enables fluidic communication between an interior of the liquid distribution tank 34 and a pump 84.

[0079] The liquid distribution tank 34 has an internal volume of around 300ml. The liquid distribution tank 34 extends for substantially the full height direction H of the cleaner head 10, but only extends partially (for a little over 50%) across the width direction W of the housing 12 of the cleaner head 10. The liquid distribution tank 34 is located at a rear end 48 of the right side wall 22, and forms part of a rear surface of the cleaner head 10 when the cleaner head 10 is assembled.

[0080] The liquid collection tank 36 comprises a main tank body 50, a front wall 56 and a surface contact member in the form of a squeegee 58. The liquid collection tank 36 is located generally centrally along the right side wall 22, such that the liquid collection tank 36 is located between the liquid distribution tank 34 and the right- side mounting member 26. A bottom surface of the liquid collection tank 36 and a bottom surface of the liquid distribution tank 34 are substantially aligned. The front wall 56 is arcuate in form, and is shaped to generally correspond to the curvature of the roller 14.

[0081] The main tank body 50 is generally cuboidal and hollow in form, and extends across substantially the entirety of the width direction W of the cleaner head 10 when the cleaner head 10 is assembled. An upper region of the main tank body 50 is open such that the hollow interior of the main tank body 50 is accessible via the upper region. The main tank body 50 has an internal volume of around 360ml, giving the liquid collection tank 36 an internal volume 20% greater than the internal volume of the liquid distribution tank 34.

[0082] The right-side mounting member 26 is releasably connected to the roller 14 and rotatably mounts the roller 14 within the housing 12. The right-side mounting member 26 is shaped and dimensioned to be received within, and engage with, the roller 14. The right-side mounting member 26 is fixedly connected to the right side wall 22, yet comprises a bearing assembly (not shown) to enable rotation of the roller 14 when connected to the right-side mounting member 26. Further details of the right-side mounting member 26 will be apparent to a person skilled in the art, and so will not be described here for the sake of brevity.

[0083] The second housing portion 20 is illustrated in Figure 3. The second housing portion 20 comprises an upper wall 74, a left side wall 76, control circuitry 78, a drive component in the form of a roller drive 80, a pump compartment 82, a pump 84, a liquid tube 86, an intermediate plate 87, and a reservoir 88. The roller 14 is rotatably connected to the second housing portion 20. A front end of the upper wall 74 is shaped to correspond to the curvature of the roller 14.

[0084] The left side wall 76 is generally elongate in form, and extends in the depth direction D of the cleaner head 10. The outer surface of the left side wall 76 is the same shape as that of the right side wall 22. The left side wall 76 is hollow in form, and defines a compartment 98 within which the control circuitry 78 is housed. The compartment 98 is sealed from any regions within the housing 12 that contain liquid in use. The control circuitry 78 comprises appropriate control circuitry for driving the roller drive 80 and the pump 84.

[0085] The roller drive 80 is located at, and fixedly connected to, a front end 100 of the left side wall 76 at a similar position to which the right-side mounting member 26 is connected to the right side wall 22 of the first housing portion 18. The roller drive 80 comprises an appropriate torque generator, such as a motor, for generating a torque to drive rotation of the roller 14. The roller drive 80 is shaped and dimensioned to fit within an interior of the roller 14, such that the roller drive 80 is located internally of the roller 14 with the roller 14 and the roller drive 80 concentric when the cleaner head 10 is assembled. The roller drive 80 is controlled by the control circuitry 78 to operate at a rate of rotation of around 900- 1000 rpm in a steady state. Steady state operational speeds in the region of 500- 1200 rpm are also envisaged. The pump compartment 82 is substantially hollow in form, and is shaped and dimensioned to receive the pump 84 therein. The pump compartment 82 is further shaped and dimensioned to correspond to a projected footprint of the liquid distribution tank 34. The pump compartment 82 is located at a rear end 102 of the left side wall 76, and extends partially in the width direction W of the cleaner head 10. The pump compartment 82 has an aperture (not shown) which enables the pump 84 to connect to the valve member 46 of the closure 44 of the liquid distribution tank 34.

[0086] The pump 84 is any appropriate pump for driving liquid from the liquid distribution tank 34 to the reservoir 88, as will be discussed in more detail hereafter. The pump 84 is controlled by the control circuitry 78 to operate in a pulsed or cyclical manner. In other examples, there may be a valve for controlling the passage of liquid from the pump 84. For example, the pump 84 may operate continuously, and the valve may be configured or otherwise controlled to open and close in a pulsed or cyclical manner.

[0087] Referring to Figure 4, according to one construction, the liquid tube 86 extends from the pump 84 to the reservoir 88 along the intermediate plate 87. The reservoir 88 is generally cuboidal in form and is elongate along an axis parallel to a rotational axis of the roller 14. The reservoir side walls are shaped such that the reservoir 88 extends across the width direction W of the cleaner head 10, and has a width in the direction W of around 100mm to 250mm. For example, it may be around 202mm in a particular embodiment or about 152.4mm in an alternative embodiment. The reservoir 88 extends for around 90% of a length of the roller 14 (where the length of the roller 14 extends along the W direction shown in Figure 1 ), although the reservoir 88 extending for at least 80% of the length of the roller 14 is also envisaged. The reservoir 88 has an interior volume of around 1440mm3to around 1155mm3, for example around 1150mm3in one embodiment. An interior volume of up to around 1571 mm3is also envisaged. The reservoir 88 has a reservoir inlet 114 and eight reservoir outlets 116, although between 6 to 10 reservoir outlets are also envisaged. The reservoir inlet

[0088] 114 comprises a circular aperture formed centrally along a reservoir inlet surface

[0089] 115 which is a side surface of the reservoir 88 facing the liquid distribution tank 34. The reservoir inlet 114 is in fluid communication with the liquid tube 86 and receives liquid from the liquid distribution tank 34. The reservoir inlet 114 has a radius in the region of 1 ,25mm, although radii in the region of 1 .00mm to 1 ,50mm are also envisaged.

[0090] The reservoir outlets 116 are spaced substantially evenly along a length of the reservoir 88 along an axis parallel to the rotational axis of the roller 14. Alternatively, the spacing between the reservoir outlets 116 nearer to the reservoir inlet 114 may be smaller than the spacing between the reservoir outlets

[0091] 116 further from the reservoir inlet 114, so that a larger amount of water is provided to a middle portion of the roller 14. Further, the reservoir outlets 116 are offset from the reservoir inlet 114 along the axis parallel to the rotational axis of the roller 14. The reservoir outlets 116 comprise generally circular apertures formed in a reservoir outlet surface 117 of the intermediate plate 87, which is a base surface of the reservoir 88. Variations in size of the reservoir inlet 114 and the reservoir outlets 116 can lead to water flow rates in the reservoir 88 of between 25ml / min and 35ml / min. In other words, liquid is delivered to a pile 122 of the roller 14 at a rate of between 25ml / min and 35ml / min.

[0092] As best seen in Figure 6, the roller 14 comprises a core 120 and a material for contacting a surface to be cleaned, where the material is in the form of a pile 122. The core 120 is generally cylindrical (with a cylindrical base surface) and hollow in form. An interior of the core 120 is provided with fixing mechanisms for releasably fixing the roller 14 to the roller drive 80 and the mounting mechanism 26. Details of such fixing mechanisms are not pertinent to the present invention, and so will not be described here for sake of clarity. A diameter of the core 120 is sufficiently large that the roller drive 80 can be received within the core 120. The pile 122 is a microfibre pile with a density of between 46,500 and 85,250 fibres / cm2. In an alternative embodiment, the roller 14 may further include a bristle pile arranged over the microfibre pile, where the bristle pile may be formed of a stiffer material, such as nylon or Polyethylene terephthalate (PET). The pile 122 has a thickness T of around 5mm to 7mm, for example, around 6.7mm in a particular embodiment. The roller 14 as a whole has a radius of around 62mm when dry, and around 58mm when wet. The roller 14 has a length of around 226mm, although lengths in the region of 225mm and 227mm are also envisaged. In other words, a surface area of the pile 122 is between 800 and 900 square centimetres.

[0093] As previously noted, the cleaner head 10 comprises an attachment mechanism 16. The attachment mechanism 16 comprises a lower portion 124 and an upper portion 126. The lower portion 124 is hingedly mounted to a central region of the upper wall 74 of the second housing portion 20, such that the lower portion 124 can move in a plane defined by the depth D and height H directions of the cleaner head 10. The upper portion 126 is hingedly mounted to the lower portion 124 to enable the upper portion 126 to move relative to the lower portion 124 in a plane defined by the width W and height H directions of the cleaner head 10.

[0094] The upper portion 126 comprises a connection formation 128, and looming, which isn’t shown for sake of clarity. The connection formation 128 comprises a catch for releasably connecting to either a wand 204 or a main unit 202 of an appliance 200. Details of the catch are not pertinent to the present invention, and will not be described here for sake of brevity. The connection formation 128 is tubular in form and solid, such that there is no airflow path therethrough. The looming provides an electrical connection between the main unit 202 of the appliance 200 and the cleaner head 10. In the assembled configuration, the roller 14 extends along the width of the cleaner head 10 between the right side wall 22 and the left side wall 76 of the respective first 18 and second 20 housing portions, at the front of the cleaner head 10. The reservoir 88 overlies a rear portion of the roller 14. The liquid collection tank 36 is located rearwardly of the roller 14, with the front wall 56 spaced slightly from the roller 14 to enable rotation of the roller 14 within the housing 12. The combined inlet / outlet 65 of the liquid collection tank 36 faces toward the upper wall 74 of the cleaner head 10. The liquid collection tank 36 extends across the width direction W of the cleaner head 10 to a similar extent to that of the roller 14 between the right side wall 22 and the left side wall 76 of the respective first 18 and second 20 housing portions. The liquid collection tank 36 and the roller 14 may each extend across at least 90% of the width of the housing 12 (i.e. dimension of the housing 12 along the direction W between the opposing side walls 22, 76). The combined inlet / outlet 65 may extend across at least 75% of a width of the liquid collection tank 36.

[0095] The liquid distribution tank 34 is located rearwardly of the liquid collection tank 36. The liquid collection tank 36 extends across the width in the direction W (between the opposing side walls 22, 76) of the housing 12 to a greater extent than the liquid distribution tank 34. The pump compartment 82, and hence the pump 84, are located adjacent to the liquid distribution tank 34 across the width W of the cleaner head 10. The attachment mechanism 16 is located centrally on the upper wall 74 such that the attachment mechanism 16 overlies the liquid collection tank 36, and is connected to the upper wall 74 at a point between the roller 14 and the liquid distribution tank 34.

[0096] To use the cleaner head 10, the attachment mechanism 16 is used to connect the cleaner head 10 to an appliance 200, as illustrated schematically in Figure 5.

[0097] The appliance 200 has a main unit 202, and a wand 204 releasably connected to the main unit 202. The cleaner head 10 can be connected to either of the main unit 202, or to the wand 204, depending on a user’s preference. The main unit 202 houses a power supply in the form of a battery 206, an airflow generator 208, and a control module 210. Power can be provided from the battery 206 to the airflow generator 208, and to the cleaner head 10 via a terminal (not shown) of the main unit 202, under control of the control module 210. Further details of the main unit 202 are not pertinent to the present invention, and will not be discussed here for sake of brevity.

[0098] The control module 210 determines whether the cleaner head 10 is attached to the main unit 202 based on a current drawn from the terminal in response to a voltage applied to the terminal. The control module 210 can also determine that a cleaner head other than cleaner head 10 is attached to the main unit 202 based on current being drawn from the terminal in response to the applied voltage. The control module 210 can then take appropriate action in controlling the main unit 202. The control module 210 can operate the airflow generator 208 in either a first mode (in which power is provided by the main unit 202 to the airflow generator 208 and an airflow is generated) and a second mode (in which power is not provided to the airflow generator 208 and an airflow is not generated). In particular, when the control module 210 determines that the cleaner head 10 is attached to the main unit 202, the control module 210 can control the operational mode of airflow generator 208 to be in the second mode (off), such that no airflow is provided by the main unit 202, as such airflow is not needed for the cleaner head 10. For other cleaner heads, the operational mode of the airflow generator 208 may instead be controlled to provide an airflow where such airflow is appropriate. When it is determined that there is no cleaner head attached to the main unit 202, the control module also controls the airflow generator to operate in the first mode.

[0099] Other methods of detecting the presence of the cleaner head are envisaged, for example including communications from the cleaner head 10 to the control module 210 via a wired and / or wireless connection, that enable the control module 210 to turn off the airflow generator 208.

[0100] With the cleaner head 10 attached to the main unit 202, power is supplied from the battery 206 of the main unit 202 via looming (not shown) to the cleaner head 10, and in particular to the control circuitry 78, the roller drive 80, and the pump 84. With other cleaner heads attached to the main unit 202, power may also be supplied to these cleaner heads from the battery 206. However, power is not provided to the terminal of the main unit 202 when it is determined that no cleaner head is attached to the main unit 202.

[0101] The pump 84 drives distribution of liquid from the liquid distribution tank 34. The pump 84 is controlled by the control circuitry 78 to operate in a pulsed or cyclical manner, as noted previously. This causes liquid to be moved from the liquid distribution tank 34, through the liquid tube 86, to the reservoir 88. In particular, liquid is driven by the pump 84 via the reservoir inlet 114 to the reservoir 88, and liquid is delivered to the pile 122 of the roller 14 via the reservoir outlets 116. In other constructions, as discussed below with reference to Figures 11 to 15c, liquid is driven by the pump 84 through a flow path 400 from the liquid distribution tank 34 to the reservoir 88 via an active cooling member 340 for cooling the roller drive 80. The pressure within the reservoir 88 is such that liquid exits the reservoir 88 through the reservoir outlets 116, and drips onto a distribution surface (not shown) located below the reservoir 88. The configuration of the reservoir 88 and the operation of the pump 84 is such that the liquid flow rate through the reservoir is around 30ml / min. The pump 84, the liquid tube 86, the reservoir 88, and the distribution surface together provide a liquid delivery assembly for delivering liquid to the roller 14 (in particular, the pile 122 of the roller 14).

[0102] The liquid pools on the distribution surface and is gradually distributed to the roller 14 by simply falling from the distribution surface onto the pile 122 of the roller 14. The roller 14 is wetted at a rate of around 30ml / min. With the roller 14 wetted by the liquid, the cleaner head 10 can be moved across a surface to be cleaned by the user. The roller drive 80 is controlled to rotate the roller 14 at around 900- OOrpm. As the roller 14 rotates and is moved across the surface to be cleaned, the roller 14 can impart a wiping force to the surface to be cleaned. The squeegee 58 is spaced from the surface to be cleaned by a small gap of about 0.1 mm to 0.2mm (for example, around 0.15mm in a particular embodiment) but it can alternatively be configured to contact the surface to be cleaned to ensure that no dirty liquid from the surface being cleaned passes toward the rear of the cleaner head 10.

[0103] The roller 14 causes displacement of liquid (from the surface to be cleaned) into the combined in let / outlet 65 of the liquid collection tank 36.

[0104] In particular, the rotation of the roller 14 and the curved nature of the front wall 56 of the liquid collection tank 36 ensures that dirty liquid, and debris, passes from the surface being cleaned to the interior volume of the cleaner head 10. The roller 14 directs the dirty liquid and debris toward the squeegee 58 and the rotational energy generated via rotation of the roller 14 pushes the dirty liquid and debris upwards along the front wall 56 into the main tank body 50 of the liquid collection tank 36.

[0105] With the configuration of the cleaner head 10 described above, the roller 14 (in particular the pile 122 of the roller 14) is maintained at a saturation level of between 25% and 28% in use. Such a saturation level has been found to be effective at cleaning a surface to be cleaned, without the need to distribute excessive levels of liquid onto the surface. It will be appreciated that the saturation level of the roller head 14 is dependent on, and can be varied based on, the nature of the pulsed or cyclical operation of the pump mentioned above. Efficient cleaning may also be achieved with a saturation level of between 10% and 30%. When desired, for example when there is no remaining liquid in the liquid distribution tank 34, the cleaner head 10 can be removed from the main unit 202 of the appliance 200. The cleaner head 10 can then be disassembled in the manner previously described to enable the liquid collection tank 36 to be emptied, and the liquid distribution tank 34 to be refilled.

[0106] It will be appreciated that locating the roller drive 80 within the roller 14 may cause the roller drive 80 to increase a temperature of an atmosphere inside the roller 14, which may reduce an amount of heat passively removed from the roller drive 80, in use. This may also restrict access to the roller drive 80 for removing heat from the roller drive 80, in use. As shown schematically in Figure 7, the housing 12 comprises a cooling compartment 125 and a roller compartment 127 at least partly delimited from each other by an inner wall 123 (which here is a part of the left side wall 76). A cooling member 300 is provided in the cooling compartment 125, while the roller 14 and roller drive 80 are located in the roller compartment 127.

[0107] The roller 14 is here rotatably mounted to the left side wall 76, and specifically to the inner wall 123, by a left-side mounting member 28. The left-side mounting member 28 here comprises a groove in the inner wall 123 into which a part of the core 120 is received; however, other forms and details of the left-side mounting member 28 will be apparent to a person skilled in the art, and so, for the sake of brevity, will not be described here. The roller drive 80 is fixedly mounted to the left side wall 76 by a drive component mount 81 .

[0108] The cleaner head 10 comprises a heat pipe 30 thermally coupled to the roller drive 80 within the roller 14. The heat pipe 30 extends from within the roller 14 towards the left-side mounting member 28 and the left side wall 76. The heat pipe 30 then passes through the left-side mounting member 28 into the cooling compartment 125 defined within the housing 12 and external to the roller 14, and is thermally coupled to the cooling member 300 located in the cooling compartment 125. The housing 12 comprises an inner wall 123 (which here is a part of the left side wall 76) at least partly delimiting the cooling compartment 125 from the roller compartment 127 of the housing 12 in which the roller 14 and roller drive 80 are located. The cooling compartment 125 may be at least part of the compartment 98 described above within which the control circuitry 78 is housed.

[0109] The heat pipe 30 comprises an evaporator end 31 thermally coupled to the roller drive 80, and a condenser end 32 thermally coupled to the cooling member 300. The heat pipe 30 also comprises a heat exchange fluid in the heat pipe 30, which changes phase to transfer heat between the evaporator end 31 and the condenser end 32. In particular, the heat exchange fluid is caused to evaporate at the evaporator end 31 due to heating from the roller drive 80, and then condensed at the condenser end 32, which is cooled by the cooling member 300, in use. In this way, the heat exchange fluid absorbs heat as latent heat at the evaporator end 31 and release the latent heat at the condenser end 32. The heat pipe 30 is thermally coupled to the roller drive 80 by a thermally conductive drive component layer in the form of a roller drive thermal pad 515a and to the cooling member 300 by a thermally conductive cooling member layer in the form of a cooling member thermal pad 515b. The roller drive thermal pad 515a and cooling member thermal pad 515b increase an efficiency of heat transfer between the heat pipe 30 and the roller drive 80, and between heat pipe 30 and the cooling member 300.

[0110] Various constructions of the cooling member 300 are envisaged, which will be described herein with reference to Figures 8 to 15c.

[0111] In a first construction, as shown in Figures 8a to 8e, a first-variant cooling member 310 comprises an annulus 311 of thermally conductive material, specifically copper. The annulus 311 is located in the cooling compartment 125. The heat pipe 30 passes into the cooling compartment 125 through the left-side mounting member 28 through a hole defined by the annulus 311. The heat pipe 30 then turns approximately 90 degrees and extends across and in contact with the annulus 311 , so that the condenser end 32 is thermally coupled to the annulus 311 . The cooling member thermal pad 515b (not shown in Figures 8a to 8e, for clarity) is arranged between (and contacts both) the heat pipe 30 and the annulus 311 , but this may be omitted and the heat pipe 30 may directly contact the annulus 311 . In this way, heat is transferred from the roller drive 80 to the annulus 311 and then dissipated in an atmosphere surrounding the annulus 311 in the cooling compartment 125. In another example, as shown in Figures 8d and 8e, the annulus 311 (or a part thereof) is located on the other side of the inner wall 123 shown in Figure 7, outside of the cooling compartment 125 and within the roller compartment 127. In any event, the annulus 311 conforms well to a geometry inside the housing 12, which provides a large surface area for heat transfer away from the annulus and also provides a compact arrangement of components in the housing 12. In this example, the heat pipe 30 does not pass into the cooling compartment 125, but instead, is thermally coupled to the annulus 311 within the roller compartment 127. The cooling member thermal pad 515b (not shown, for clarity) is arranged between (and contacts both) the heat pipe 30 and the annulus 311 , but this may be omitted and the heat pipe 30 may directly contact the annulus 311 . As shown in Figures 8a and 8e, the heat pipe 30 may include a bend 802, so that it conforms to a shape of the roller drive 80, but heat pipes of other structures may be used in alternative examples.

[0112] In a second construction, as shown in Figure 9, a second-variant cooling member 320 comprises a thermally conductive pipe in the form of a winding 312 of thermally conductive material, specifically copper. The heat pipe 30 extends into the cooling compartment 125 and turns approximately 90 degrees to extend across the winding 312, so that the condenser end 32 is thermally coupled to the winding 312. The cooling member thermal pad 515b is arranged between the condenser end 32 and the winding 312, but this may be omitted and the heat pipe 30 may directly contact the winding 312. In the example shown, the winding 312 loops back and forth within the cooling compartment 125, but other examples are envisaged. For instance, the winding 312 could take a spiral path in the cooling compartment 125. In any event, the winding 312 may provide an improved surface area and / or reduced weight.

[0113] In a third construction, as shown in Figure 10, a third-variant cooling member 330 comprises a block 313 of thermally conductive material, specifically copper, extending from the cooling compartment 125 and along the housing 12 in the depth direction D. In particular, the block 313 is substantially cuboidal, and extends above the control circuity 78. The control circuitry 78 is physically and thermally separated from the block 313 by a barrier 318 defined by the housing 12. The third-variant cooling member 330 comprises fins 315a, 315b on an upper surface of the block 313. Providing the elongate block 313 and the fins 315a, 315b may provide improved length and / or surface area, thereby improving thermal efficiency. The arrangement of the third-variant cooling member 330 relative to the housing 12 may also provide a compact arrangement of components in the housing 12.

[0114] The first to third constructions, and foreseeable variants, each provide passive cooling of the condenser end 32 of the heat pipe 30, specifically by conducting heat away from the condenser end 32 with a thermally conductive material, and exchanging the heat with an atmosphere surrounding the thermally conductive material. In particular, it will be appreciated that the annulus 311 , the winding 312, and / or the block 313 of thermally conductive material may be considered a “heat sink” which conducts and exchanges heat between the condenser end 32 and a cooling source such as the atmosphere which includes cooling fluid in the form of air. In other constructions, as will be described below in relation to Figures 11 to 15c, the cooling source includes a cooling fluid in the form of liquid from the liquid distribution tank 34, and this liquid is used to provide active cooling of the condenser end 32. In particular, as shown schematically in Figure 11 , an alternative cleaner head 11 comprises a flow path 400 which passes liquid from the liquid distribution tank 34 to the roller 14 via the pump 84 and an active cooling member 340. The flow path 400 comprises a first liquid tube 410 extending from the pump 84 to the active cooling member 340 and a second liquid tube 420 extending from the active cooling member 340 to the reservoir inlet 114.

[0115] In a fourth construction, as shown in Figure 12, a fourth-variant cooling member 350 comprises a block 343 of thermally conductive material, in a similar way to the third construction. In this case, the block 343 is located within the cooling compartment 125. The block 343 is substantially cuboidal, and comprises fins 345 extending from a surface of the block 343. The fourth-variant cooling member 350 comprises a coupling portion 319 into which the condenser end 32 is inserted to thermally couple the condenser end 32 with the block 343. The cooling member thermal pad 515b (not shown, for clarity) is arranged between (and contacts both) the condenser end 32 and the block 343, but this may be omitted and the condenser end 32 may directly contact the block 343. The fourth-variant cooling member 350 also comprises a passage 314, which is defined by a hole 317 through the block 343. Liquid from the liquid distribution tank 34 is passable through the passage 314 to cool the block 313 and thus the condenser end 32. This is by the passage 314 being fluidically connectable, such as by suitable connections (not shown) to the first and second liquid tubes 410, 420. In this way, the flow path 400 comprises the passage 314, and in this example, the liquid tubes 410, 420 may be formed of a different material from the block 343. For example, the tubes 410, 420 may be formed of silicon, whereas the block 343 may be formed of copper. In another example not shown in the Figures, the flow path 400 instead comprises a single liquid tube that passes through the passage 314, so that the liquid tube provides a boundary between the block 343 and liquid in the liquid tube. In either case, the fourth construction provides a further use for the liquid in the liquid distribution tank 34 to improve cooling of the condenser end 32, and thus the roller drive 80.

[0116] Figures 13 and 14 show a fifth construction, in which a fifth-variant cooling member 360 comprises a thermally conductive pipe in the form of a copper pipe 500 defining the passage 314. The copper pipe 500 is fluidically connectable between the first and second liquid tubes 410, 420. Similarly, the liquid tubes 410, 420 may be formed of a different material (e.g., silicon) from the copper pipe 500. The copper pipe 500 forms a pipe loop 530 which is thermally coupled to the condenser end 32 via the cooling member thermal pad 515b (as discussed above), although, in other examples, this cooling member thermal pad 515b may be omitted. Liquid is received from the first liquid tube 410 through a pipe inlet 510 to the copper pipe 500 and passed to the second liquid tube 420 through a pipe outlet 520 of the copper pipe 500. A flow disruptor in the form of a helical insert 540 is provided in the inlet 510 to impart a swirl into the liquid flowing through the copper tube 500, in use, which may improve a rate of heat transfer between the copper tube 500 and the liquid. It will be appreciated that, while not shown in the figures, any of the other constructions described herein which utilise the liquid from the liquid distribution tank 34 may comprise such a flow disruptor. The copper pipe 500 here extends from the cooling compartment 125 into the roller compartment 127, and at least partly into the roller 14. This may allow a length of the copper pipe 500 in contact with the condenser end 32 to be increased, which may improve a heat capacity of the fifth-variant cooling member 360. Alternatively, the copper pipe 500 may be arranged entirely outside the roller compartment 127, either entirely within the cooling compartment 125 or partially within the cooling compartment 125 and partially external of the housing 12. For example, the copper pipe 500 may have a similar structure and may be similarly arranged relative to the heat pipe 30 and the compartments 125, 127 as the winding 312 in the second construction.

[0117] The block 343 of the fourth construction and / or the copper pipe 500 of the fifth construction may be thought of as a “heat sink”, as described above for the first to third constructions, but in each of the fourth and fifth constructions the heat sink is also actively cooled using liquid from the liquid distribution tank 34. Finally, Figures 15a and 15b show a sixth construction, in which a sixth-variant cooling member 370 comprises a manifold 600 defining a chamber 630 into which the condenser end 32 is inserted. The manifold 600 comprises a manifold inlet 610 for connection to the first liquid tube 410 and a manifold outlet 620 for connection to the second liquid tube 420. The chamber 630 comprises an inlet compartment 615 for passing liquid from the inlet 610 to the condenser end 32 and an outlet compartment 625 for passing liquid from the condenser end 32 to the outlet 620. Each of the manifold inlet 610 and the manifold outlet 620 is inclined at an angle A, B of approximately 45 to 75 degrees with respect to the respective chamber the manifold inlet 610 or manifold outlet 620 communicates with. While the angles A and B are the same in this example, they may be different in other examples. Further, in an alternative embodiment as shown in 15c, the manifold inlet 610 may be arranged at the side of the chamber 630, approximately parallel with a cross-section profile of the heat pipe 30. In each case, a flow guide 640 is located in the chamber 630 to delimit the inlet and outlet compartments 615, 625. The flow guide 640 extends approximately perpendicular from a wall of the chamber 630, and a gap between the flow guide 640 and the heat pipe 30 has a height H64o of approximately 0.5mm to 2mm. Specifically, the flow guide 640 prevents a return flow of fluid from the outlet compartment 625 to the inlet compartment 615. This, in turn, prevents liquid entering the chamber 630 via the inlet compartment 615 being heated by liquid leaving the chamber 630 via the outlet compartment 625. In other words, the flow guide 640 reduces flow circulation and hotspots in the chamber 630. The manifold 600 is also shaped so as to encourage a flow of liquid towards the manifold outlet 620, specifically by providing a chamber wall 660 that slopes towards the manifold outlet 620. This improves an ability of the liquid flowing in the manifold 600 to carry heat away from the condenser end 32, in use.

[0118] As best shown in Figure 15b, the manifold 600 is located partly in the cooling compartment 125, and comprises a receiving portion 650 that extends out of the cooling compartment 125 and into the roller compartment 127. The condenser end 32 is received in the receiving portion 650 and extends into the chamber 630, which is located in the cooling compartment 125. The manifold 600 comprises a manifold seal 680 (which is shown in Figures 15a and 15c, but not in Figure 15b, for clarity), which seals the condenser end 32 in the chamber 630. The manifold 600 also comprises a manifold cap 690, which seals and at least in part defines the chamber 630. A further seal (not shown in the figures), such as a rope seal may be arranged between the chamber 630 and the manifold cap 690.

[0119] In use, liquid from the first liquid tube 410 is received in the manifold inlet 610 and passed through, the chamber 630 in direct contact with the condenser end 32. Placing the condenser end 32 in direct contact with the liquid in the manifold 600 may improve a rate of heat transfer between the liquid and the condenser end 32. The heated liquid is then passed from the chamber 630 to the second liquid tube 420 via the manifold outlet 620, and ultimately to the roller 14 via the reservoir 88. It will be appreciated that increasing a surface area of the condenser end 32 in the chamber 630, such as by the condenser end 32 extending into the chamber 630 to a greater extent, may further improve a heat transfer efficiency of the sixth-variant cooling member 370. In one example, the condenser end 32 may extend by a distance of L30 into the chamber 630, where L30 may range from about 7mm to 9mm.

[0120] Whilst particular examples and embodiments have thus far been described, it should be understood that these are illustrative only and that various modifications may be made without departing from the scope of the invention as defined by the claims. For example, while the drive component 80 is shown as entirely within the roller 14 in the figures, in some embodiments, the drive component 80 may comprise a portion within the roller 14 and a portion external of the roller 14, or may be entirely external of the roller 14. For example, the values of various parameters and dimensions described in conjunction with a specific embodiment above may be varied within a reasonable tolerance range that will be apparent to a person skilled in the art without significantly modifying operation of the cleaner head 10. Moreover, it will be appreciated that any other suitable cooling members, or locations, either active or passive, may be provided in examples.

Claims

Claims1 . A cleaner head for an appliance, the cleaner head comprising: a roller for contacting a surface to be cleaned; a drive component for driving motion of the roller, wherein a portion of the drive component is located within the roller; and a heat pipe comprising an evaporator end thermally coupled to the portion, and a condenser end opposite to the evaporator end.

2. The cleaner head of claim 1 , wherein the condenser end is located external to the roller.

3. The cleaner head of claim 1 or claim 2, comprising a cooling member for transferring heat between the condenser end and a cooling source, the cooling member thermally coupled to the condenser end.

4. The cleaner head of claim 3, wherein the cooling member is located entirely external to the roller.

5. The cleaner head of claim 3, wherein the cooling member is located at least partly within the roller.

6. The cleaner head of claim 3 or claim 4, wherein the cooling member is located entirely external to a housing of the cleaner head comprising the roller.

7. The cleaner head of any one of claims 3 to 5 wherein the cooling member is located partly, or entirely, within a housing of the cleaner head comprising the roller.

8. The cleaner head of any one of claims 3 to 7, wherein the cooling member comprises a heat sink thermally coupled to the condenser end of the heat pipe.

9. The cleaner head of claim 8, comprising a thermally conductive cooling member layer located between and contacting both the condenser end and the heat sink.

10. The cleaner head of claim 8 or claim 9, comprising a thermally conductive drive component layer located between and contacting both the evaporator end and the portion of the drive component.

11. The cleaner head of any one of claims 8 to 10, wherein the heat sink comprises one or more thermally conductive fins.

12. The cleaner head of any one of claims 8 to 11 , wherein the cooling source comprises a cooling fluid, and the heat sink comprises a passage through which the cooling fluid is flowable.

13. The cleaner head of claim 12, wherein the heat sink comprises a thermally conductive pipe defining the passage.

14. The cleaner head of claim 12, wherein the heat sink comprises a block of thermally conductive material, and the passage is defined through the block of thermally conductive material.

15. The cleaner head of any one of claims 12 to 14, comprising a flow disturber for disturbing a flow of the cooling fluid through the passage.

16. The cleaner head of any one of claims 3 to 15, wherein the cooling member comprises a manifold, the manifold comprising a chamber in which the condenser end is located, and wherein the cooling source is a cooling fluid, and the cooling fluid is passable through the chamber to contact the condenser end.

17. The cleaner head of claim 16, wherein the manifold comprises an inlet through which the cooling fluid is receivable into the manifold, and an outlet through which the cooling fluid is expellable from the manifold, and the chamber is fluidically coupled between the inlet and the outlet.

18. The cleaner head of claim 17, wherein the inlet and the outlet are located on the same side of the manifold.

19. The cleaner head of claim 17 or claim 18, wherein the manifold comprises a flow guide defining a flow path through the chamber, wherein the condenser end is located in the flow path.

20. The cleaner head of claim 19, wherein the chamber comprises an inlet compartment through which the cooling fluid is flowable from the inlet to the condenser end, and an outlet compartment through which the cooling fluid is flowable from the condenser end to the outlet, and wherein the flow guide at least partly delimits the inlet compartment and the outlet compartment.

21. The cleaner head of any one of claims 16 to 20, comprising a seal for sealing the condenser end in the chamber.

22. The cleaner head of any one of claims 3 to 21 , comprising a liquid distribution tank for storing liquid to be distributed to the roller, wherein the cooling source comprises liquid from the liquid distribution tank.

23. The cleaner head of claim 22, comprising a flow path through which the liquid in the liquid distribution tank is passable from the liquid distribution tank to the cooling member.

24. The cleaner head of claim 23, comprising a filter arranged in the flow path between the liquid distribution tank and the cooling member.

25. The cleaner head of any one of claims 1 to 24, comprising a housing and a mounting member for rotatably mounting the roller in the housing, wherein the heat pipe extends towards the mounting member from the portion of the drive component.

26. An appliance comprising the cleaner head of any one of claims 1 to 25.

Images