GB2604168A

GB2604168A - Cleaner head for a vacuum cleaner

Info

Publication number: GB2604168A
Application number: GB2102786.7A
Authority: GB
Inventors: Dodgson Oliver
Original assignee: Dyson Technology Ltd
Current assignee: Dyson Technology Ltd
Priority date: 2021-02-26
Filing date: 2021-02-26
Publication date: 2022-08-31
Anticipated expiration: 2041-02-26
Also published as: GB202102786D0; GB2604168B; CN116981385A; WO2022180388A1

Abstract

A cleaner head 114 for a vacuum cleaner comprises an airflow path for providing suction to a surface to be cleaned, a housing and at least one driven agitator 122 for engaging the surface to be cleaned. The agitator(s) is/are mounted within the housing. An outer skirt 116 is arranged around the perimeter of the housing and is arranged to be able to contact the surface to be cleaned during use, for example to provide a partial seal to improve suction. The outer skirt 116 is sufficiently flexible such that it is able to contact and be deformed by the agitator during use. A first portion of the skirt may move inwardly and a second portion may move outwardly when subjected to an external force. This may enable the cleaner head to clean into corners better.

Description

Cleaner Head For A Vacuum Cleaner

Field of the Invention

The invention relates to a cleaner head for a vacuum cleaner. The invention also relates to a vacuum cleaner comprising a cleaner head.

Background of the Invention

The present invention relates primarily but not exclusively to hand held vacuum cleaners for cleaning a floor. An example of such a vacuum cleaner is the Dyson VII Absolute'', this vacuum cleaner comprises a main body which houses a motor for providing suction, a separation system for removing dirt and debris from the air and a battery for providing power to the motor. The main body is attached to a neck mounted to a detachable cleaner head, which comprises a bottom surface for engaging with the floor onto which a movable cleaning element is attached. The cleaner head also comprises a housing in which the cleaning element, a motor and parts of the drive mechanism for the cleaning element are provided. The cleaner head housing also defines a suction airflow path which passes through an inlet in the housing. This airflow path extends from the cleaner head, up through the neck and into the main body of the vacuum cleaner via a conduit, which extends into the separation system. In vacuum cleaners like this the separation system will typically comprise either a bag which acts as a filter to remove debris from the air and/or a cyclonic separation system. The cleaning element is typically driven to move in a way that agitates dust and debris from the floor and allows it to be entrained in the airflow being sucked into the cleaner head via the airflow path.

Vacuum cleaners of the prior art also include upright vacuum cleaners, configured to be able to stand on the floor and be self-supporting, which are typically bigger and heavier than hand held vacuum cleaners.

The cleaning element used in a vacuum cleaner is typically provided in the form of a roller with bristles, filaments, brushes or the like that is arranged to rotate about an axis parallel to the floor and to agitate the floor covering / floor surface in order to dislodge dirt and debris that is then sucked up into the cleaner. The planform of the housing may surround the cleaning element. Depending on the configuration the housing may prevent the cleaning element from agitating a surface close to a wall, particularly where two walls meet at a corner in a room. Exposing one or more portions of the cleaning element may assist in enabling a cleaning element in reaching into a corner, but may risk reduction in effective suction (that would otherwise be assisted by the seal with the floor provided at -2 -least in part by the housing) and/or risk a moving part of the cleaning element interfering with the wall/skirting board or the like, which might be scratched marked or otherwise damaged.

U3201 1225763 discloses a flexible impact-cushioning bumper which can be fitted onto a variety of vacuum cleaner beads in order to protect them and the surrounding furniture from scuffing and denting during use.

JP2002369771 discloses a passive suction tool for a vacuum cleaner, with no moving agitators, that can distort when pressed into corners due to its elastic main body. U5201 8206686 discloses an autonomous robot vacuum cleaner with a body in the shape of a rounded triangle that is able to provide improved corner cleaning due to the pointed shape of its body.

It is an object of the present invention to provide an improved cleaner head for a vacuum cleaner. Alternatively or additionally it is an object of the present invention to provide a cleaner head capable of improved cleaning into corners or tight spaces.

Summary of the Invention

The present invention provides a cleaner head for a vacuum cleaner. The cleaner head comprises an airflow path for providing suction to a surface to be cleaned, a housing and at least one driven agitator for engaging the surface to be cleaned. The at least one driven agitator is mounted within the housing. An outer skirt is arranged around the perimeter of the housing and is arranged to be able to contact the surface to be cleaned during use. In embodiments, such an arrangement may be advantageous as it allows the outer skirt to improve the suction provided by the cleaner head by creating a partial seal against the surface to be cleaned. The outer skirt is sufficiently flexible such that it is able to contact and be deformed by the agitator during use. In embodiments, such an arrangement may be advantageous as it allows the agitator to get closer in towards a wall or corner during use, allowing the cleaner head to clean into hard-to-reach spaces.

In an embodiment of the invention, the agitator is arranged to be driven relative to the cleaner head, preferably moving in a plane. This plane may be parallel to the surface to be cleaned. This plane may be generally aligned with the surface to be cleaned. The agitator may be arranged to perform rotational and/or translational movement within the plane, and optionally a combination of two or more different types of motion (e.g. two different types of rotational motion). This may effectively allow the agitator to perform a scrubbing and sweeping motion simultaneously, which may be able to remove dirt and debris more effectively than either motion individually. In other embodiments the agitator -3 -may be arranged to move with only rotational movement within the plane. In other embodiments the agitator may be arranged to move with only translational movement within the plane, for example side to side, or sweeping out a closed loop path of motion in a cyclical mariner.

In an embodiment of the invention the agitator may comprise a brush bar which rotates about a longitudinal axis parallel to the surface to be cleaned. This brush bar may be cylindrical in shape. The surface of this brush bar may be covered in a multitude of bristles. This embodiment may be advantageous when cleaning carpeted surfaces as the bristles of the brush bar may be able to engage with the carpet fibres along a curved path, causing dust arid debris that is buried in the fibres of the carpet to be brought to the surface as the brush bar rotates.

According to an embodiment, the agitator may be arranged to be driven relative to the cleaner head so that it rotates in one direction (e.g. clockwise or anticlockwise) about a moving axis which moves around a path in an opposite direction (e.g. moving in an anticlockwise or a clockwise direction around the path). The agitator may be so arranged that the moving axis is moved around a closed path in cycles at a frequency which is higher than the frequency of rotation of the agitator. For example, the moving axis may complete three cycles of movement around the closed path for every complete rotation of the driven agitator. Such a three to one ratio of movement, in combination with a triangular-shaped driven agitator allow the vertices of the triangle to each visit all four corners of a notional square during one complete cycle of movement. In embodiments of the invention, the driven agitator is typically arranged to be driven such that it rotates about an axis perpendicular to the plane of its planform. In use, the (optionally moving) axis of rotation will therefore typically be vertical, assuming that the floor is flat and horizontal. The agitator may be arranged so that the path around which the moving axis moves is a round path, preferably a closed round path. For example, the notional closed path traced by the centre of the driven agitator may be a circle. A circular path of motion is relatively easy to implement.

Such an arrangement, whilst being comprised of rotational motion may nevertheless cover a generally square-edged area, as explained in further detail in the illustrated embodiments. Embodiments of the invention enable the use of rotating driven agitators which can reach into the corners of a room, using a combination of rotational motion.

In other embodiments the path around which the moving axis moves may be a non-circular path, and in other embodiments the path may be a rounded square. -4 -

It may be that the agitator has a substantially triangular planform. Each of the sides of the triangular planform may be formed by convexly curved lines. Each of the convexly curved lines may have a constant radius of curvature. The triangular planform may be in the shape of a Reuleaux triangle. In other embodiments the agitator may have a substantially square planform. In other embodiments the agitator may have a planform having a pointed end. This pointed end may be arranged to move in such a way as to assists in cleaning into corners.

It may be that the rotational motion of the driven agitator is so arranged that the planform of the area covered (swept out) by the driven agitator includes at least one substantially straight edge. It may be that the rotational motion of the driven agitator is so arranged that the planform of the area covered (swept out) by the driven agitator has four discernible sides. The sides may be generally straight or slightly curved. The corners of the four sided shape may be rounded.

In embodiments of the invention, the shape and rotational motion of the driven agitator may be so arranged that the planform of the area (within the frame of reference of the cleaning head) covered (i.e. swept out) by the driven agitator covers more than 90% (optionally more than 95%, and possibly more than 98%) of a notional rectangle or square that envelopes the entire area so covered (swept out). The notional rectangle or square has straight edges and corners that are formed by 90 degree right-angles. Such good coverage of a rectilinear shape may be of benefit in a floor cleaning apparatus designed to clean the floor of rooms that have straight walls and / or right-angled corners.

The agitator may comprises multiple bristles. In other embodiments the agitator may have brushes. In other embodiments the agitator may comprise a pad.

The cleaning head may comprise at least Iwo driven agitators for example arranged side by side such that the planform of the area (within the frame of reference of the cleaning head) covered (swept out) by the driven agitators covers more than 90% (optionally more than 95%, and possibly more than 98%) of a notional rectangle that envelopes the entire area so covered (swept out). Thus, in embodiments, the cleaner head may comprise a pair of driven agitators in the housing which are configured to move within an oblong envelope of movement. A pair of agitators is able to provide more effective cleaning than that provided by a single agitator, as it is less likely that there will be dead spots within the cleaner head where dust and debris accumulates without being sucked into the airflow path.

In other embodiments the agitators may be configured to move within a square envelope of movement. In other embodiments the cleaner head may comprise more than -5 -two driven agitators. It may be that the housing of the cleaner head has an oblong planform shape. In other embodiments the housing of the cleaner head may have a rounded shape. The cleaner head may have a substantially rectangular shape. The top surface of the cleaner head housing may have a hard outer shell. The cleaner head housing may be a hard outer shell from which the outer skid extends.

The cleaner head may be arranged such that the outer skirt extends to provide a protective barrier around the agitator during use. This protective barrier is advantageous as it acts to reduce the occurrence of scratches or dents caused by any interaction between the driven agitators and any external objects that the cleaner head might come into contact with.

Preferably, the outer skid is made of a resilient material, such that it is able to be deformed and then return to a neutral position. The outer skid may be made of silicone. The outer skirt may be made of rubber or a rubber-like material. The outer skid may be made of any resilient material that is able to return to a neutral position after it has been deformed by an external force. This will allow the user to press the cleaner head into corners and tight spaces during cleaning without fear of damaging the cleaner head, the agitator(s) therein, or the walls surrounding the floor area. The skid may be configured to be deformed by a maximum deflection beyond which the skirt would be permanently deformed or damaged. Preferably such a maximum deflection would not be caused during routine use of the vacuum head. It is also preferable that the force required to cause a movement of the skirt beyond the maximum deflection would be much greater than the forces that would typically be sustained by the vacuum cleaner head during a typical and average lifetime of use of the head. The skirt may have a maximum deflection which is less than 10cm and optionally less than 5cm. The skid may have thickness greater than 2mm.

According to embodiments, when the outer skid is in its neutral non-deformed position it may always intersects the path of the agitator at least once during a complete cycle of movement of the agitator. In other embodiments, when the outer skid is in its neutral non-deformed position it may not intersect the path of the agitator during a complete cycle of movement of the agitator. In another embodiment, when the outer skirt is in its neutral non-deformed position it may continuously intersect the path of the agitator as the agitator is driven. This may be advantageous as it allows the agitators to clean over an area that may be greater than the area defined by the planform of the cleaner head housing and/or of the planform of the skid of the cleaner head. -6 -

It may be that the skirt is so configured that an external force which causes a first portion of the skirt to move inwardly from the perimeter of the planform shape of the skirt when in its neutral position will also cause a second portion of the free end of the skirt to move outwardly from the perimeter of that planform shape. This may enable the skirt to adopt a shape which conforms more closely to the shape of an object against which the skirt is pushed. This is advantageous as it improves the cleaner head's ability to clean into corners and allows the outer skirt to create a partial seal around the area to be cleaned. For example when cleaning the corner of a room, the outer skirt may improve the suction into the corner by directing airflow through the deformed edge of the cleaner head. It may be that pushing the skirt into a corner causes sides of the skirt to be urged inwardly and the portion of the skirt nearest the corner to extend outwardly, thus intruding further into the corner.

According to embodiments, the outer skirt may extend from the housing and terminate at a free end. The free end of the skirt may define a closed loop. In other embodiments the outer skirt may extend around at least 90% of the outer perimeter of the cleaner head without defining a closed loop.

In another embodiment the skirt may be configured such that it extends from the housing and flares downwardly and outwardly away from the top surface of the housing towards the surface to be cleaned. In this embodiment the planform of the area surrounded by the base of the outer skirt would be larger than the planform of the area of the cleaner head housing itself. The skirt may be arranged to assist in applying suction to a particular region of the surface to be cleaned. It may be that the outer skirt completely surrounds the area of the surface to be cleaned over which suction is applied.

The above described aspects of the present disclosure which relate to the ability of the outer skirt to deform in a way that assists in cleaning in the corners of a room may have application independently of the skirt interacting with the driven agitator. Thus, according to another embodiment there is a vacuum cleaner head comprising a housing and a resilient outer skirt arranged around the perimeter of the housing. The resilient outer skirt may have a neutral position which the outer skirt reverts to when not deformed by an external force. The outer skirt may extend from the housing and terminate at a free end which defines a first planform shape when the skirt is in its neutral position. The skirt may be configured such that an external force which causes a first portion of the free end of the skirt to move inwardly from the perimeter of the first planform shape is able to cause a second portion of the free end of the skirt to move outwardly from the perimeter of the first planform shape. This may enable the free end of the skirt to adopt a second planform -7 -shape which conforms more closely to the shape of an object against which the skirt is pushed than the first planform shape. This provides the cleaner head with an improved ability to clean into corners and tight spaces without causing any damage to the cleaner head or the walls abutting the area to be cleaned. The cleaner head of this embodiment preferably also includes a driven agitator which is mounted within the housing, but as mentioned above, the skirt and agitator do not necessarily need to be able to contact each other during normal use.

According to another embodiment there is a vacuum cleaner which has a cleaner head as described herein. The vacuum cleaner may be in the form of a dry cleaner. The vacuum cleaner may be in the form of a wet cleaner.

It will of course be appreciated that features described in relation to one aspect of the present invention may be incorporated into other aspects of the present invention.

Description of the Drawings

Embodiments of the present invention will now be described by way of example only with reference to the accompanying schematic drawings of which: Figure 1 shows an external view of a vacuum cleaner according to a first embodiment of the invention; Figure 2 shows a schematic representation of a side view of the cleaner head according to a first embodiment of the invention; Figure 3 shows a schematic planform representation of the agitators positioned on the base of the cleaner head according to a first embodiment of the invention; Figure 4 shows a schematic planform representation of the base of the cleaner head where the cleaner head is pushed against a vertical surface according to a first embodiment of the invention; Figure 5 shows a schematic planform view of a pair of agitators on the base of the cleaner head according to a first embodiment of the invention; Figure 6 shows a schematic planform view of a single agitator in a starting position according to a first embodiment of the invention; Figure 7 shows a schematic planform view of a single agitator in successive positions as it is driven along its path according to a first embodiment of the invention; Figure 8 shows a schematic planform view of a single agitator in successive positions as it is driven along its path according to a first embodiment of the invention; -8 -Figure 9 shows a schematic planform view of a single agitator in successive positions as it is driven along its path according to a first embodiment of the invention; and Figure 10 shows a schematic planform view of a pair of agitators on the base of the cleaner head according to a second embodiment of the invention.

Detailed Description

Figure 1 shows an external view of a vacuum cleaner 100 according to a first embodiment of the invention. The vacuum cleaner 100 comprises a cleaner head 114, a neck 108, a main body 102, a handle 106 and a bin 104. The handle 106 is mounted directly onto the main body 102 and is positioned such that a user can operate the vacuum cleaner from a standing position. The main body 102 and handle 106 move together as a relatively rigid body. The handle 106 comprises a user interface (not shown) which enables the vacuum cleaner functions to be controlled by the user. Mounted within the main body 102 is a motor (not shown) which provides suction to the cleaner head 114 via a conduit which extends from the main body, down the neck 108 to the cleaner head 114. This conduit forms an airflow path (illustrated by arrow 110) from the cleaner head 114, where air, dust and debris is sucked in, to the main body 102 of the vacuum cleaner.

A separation system is also mounted within the main body. The air is passed through this system, which separates the dust and debris into the bin 104 and then passes through a post filter (not shown) before being released back into the atmosphere. A battery (not shown) is also mounted within the main body 102, which provides power to the motor and to elements of the cleaner head 114. The bottom surface of the cleaner head 114 faces and is in contact with the surface to be cleaned. The neck 108, which is in the form of a long cylindrical shaft, attaches at one end to the cleaner head 114 and at its other end to the main body 102, and provides the length needed such that the user does not need to bend over in order to maintain contact between the cleaner head and the floor. The cleaner head 114 is pivotally attached to the neck, at an attachment point 112, such that when the user applies a force to the vacuum cleaner 100 the cleaner head 114 is able to twist in accordance with that motion. The pivoting connection between the cleaner head 114 and the main body 102, allows the user to move the vacuum cleaner back and forth over the floor, with the angle of the shaft of the neck 108 relative to the floor changing, while the cleaner head remains parallel to the floor. The cleaner head 114 is detachable from the neck 108, and the neck is detachable from the main body 102.

The cleaner head 114, as illustrated by a schematic in figure 2, comprises a housing 118, an airflow path (illustrated by arrow 110), two driven agitators 122 and their drive mechanisms 120, a motor (not shown) that drives that agitators and is powered by the battery in the main body 102 and a flexible outer skirt 116 arranged around the perimeter of the housing 118. When in use the bottom surface of the cleaner head 114 faces the surface to be cleaned. The top surface of the cleaner head housing 118 has a hard shell. The cleaner head 114 is arranged to be detachably connectable to the neck 108 of the vacuum cleaner, which provides a conduit for the airflow path 110. Dust and debris that is loosened by the agitators 122 is sucked up through this airflow path into the main body 102 of the vacuum cleaner 100.

The housing 118 of the cleaner head 114 has a pair of driven agitators 122 mounted within it, which are arranged to be driven relative to the cleaner head with movement in a plane that is parallel to the bottom surface of the cleaner head. Each agitator 122 is arranged to rotate about a first axis. The first axis is movable and is driven around a closed round path.

It will be seen in figure 3 that each agitator 122 has a generally triangular shape, with each side of the triangle being curved. The curved sides are convex, and are in the shape of an arc of a circle. The shape is in the same form as a Reuleaux triangle. The three sides meet at three vertices. The triangle thus has three generally pointed regions, each corresponding to a respective vertex.

The planform surface of each agitator 122 is covered in a plurality of bristles (not shown) which allows the agitator to agitate dust and debris as it sweeps across the surface to be cleaned. The sides of the agitator, perpendicular to the plane of the planform, also include a plurality of bristles which stick out in a direction generally parallel to the plane of the planform of the agitator.

The flexible outer skirt 116 is mounted on the housing 118 such that it flares downwardly and outwardly away from the top surface of the housing towards the surface to be cleaned, terminating in a free end. Figure 3 shows a neutral position of the skirt as a solid line 116, when it is not subject to any external forces. After the skirt has been deformed by an external force, it will return to the neutral position. The skirt is attached to the housing 118 so that the top edge of the skirt 116 is flush with the top surface of the housing. The skirt runs completely around the oblong perimeter of the planform of the housing 118. The skirt forms a closed loop. The planform of the area surrounded by the free end of the skirt is larger than the planform of the area of the cleaner head housing itself. The skirt is made of silicone which is resilient and will return to its neutral shape -10 -when not deformed by an external force (e.g. when the user pushes the cleaner head up against an object). The skirt completely surrounds the area of the surface to be cleaned over which suction is applied.

The flexible outer skirt 116 has a thickness of 4mm. The vertical distance from the top surface of the cleaner head housing 118 to the bottom surface of the cleaner head is 50mm. Since the skirt is flared and is made up of a closed loop, it has an inner perimeter which is smaller than its outer perimeter. The inner perimeter surrounds the planform of the cleaner head housing and is 600mm, the outer perimeter surrounds the area of the surface to be cleaned and is 700mm.

The flexible outer skirt 116 extends down towards the surface to be cleaned such that in use the free end of the skirt is just able to make contact with the floor. As illustrated in figure 4, when the cleaner head 114 is pressed against two walls 128 which define a corner of a room, the flexible outer skirt 116 will deform inwardly and will be pressed in more tightly against the floor, creating a partial seal and allowing an increased level of vacuum suction into the corner. When one portion of the skirt is deformed inwardly, this may cause another part of the skirt to be pushed outwards from its neutral position, allowing the skirt to deform to a shape that is complementary to the shape of the area to be cleaned. This aids in the collection of the dust and debris that has been agitated by the agitators 122. The skirt has a rigidity such that when deformed the planform of the area surrounded by the skirt will only change by a maximum of 10% when an external force is applied.

As each agitator 122 is driven around its closed path, it sweeps out an area that is generally square (as shown in figure 9). The pair of agitators side by side sweep out an area that is generally oblong. Over 90% of the area bounded by the rectangle illustrated by the dashed line 124 in figure 3 is covered by the movement of the agitators. The rectangle 124 also contains all of the area covered by the movement of the agitators. As shown in figure 3, this rectangle 124 extends beyond the planform of the area surrounded by the base of the skirt 116. In use, as each driven agitator 122 moves through a complete cycle of movement at least one part of the agitator is continuously in contact with the outer skirt 116. When the agitator 122 pushes against the skirt, the skirt deforms and allows the agitator to continue along its driven path. The skirt is arranged around the perimeter of the cleaner head so that the skirt provides a barrier between the side edge of the agitator and any external objects or vertical surfaces that the cleaner head comes into contact with.

As illustrated in figure 6, the agitators 122 are each arranged to rotate clockwise about an axis of rotation 126 that remains fixed in position relative to the agitator. Each agitator's axis of rotation is perpendicular to the plane of the agitator. The agitator's axis of rotation 126 is positioned at the centre of the agitator. The drive mechanism 120 for each agitator 122 causes the agitators axis of rotation 126 to move around a circular path 132 in an anticlockwise direction as the agitator 122 rotates clockwise. For every complete rotation of an agitator about its axis (in the frame of reference of the cleaner head) the agitator completes three circuits of the circular path 132 it follows. The moving axis 126 of the agitator 122 is moved around the circular path 132 in cycles at a frequency which is three times higher than the frequency of rotation of the agitator 122.

The shape of the agitators 122 and their motion are the same for each agitator, so the following description whilst limited primarily to a single agitator applies to both. The motion of each agitator and the notional square 136 encompassing the area swept out (within the reference frame of the cleaner head) by it are illustrated by figures 6 to 9.

Figure 6 shows an agitator 122 in a starting position. An arrow 134 is provided on the drawing of the agitator shown in Figure 6 merely to aid understanding of the motion, the arrow 134 extending from the axis of rotation 126 of the agitator (the centre of the agitator) to a first pointed region of the agitator. As shown in Figure 6, the pointed region of the agitator is shown extending into the corner of the notional square 136 shown as broken lines.

Figure 7 shows the agitator in the same position as shown in Figure 6, together with two further images of the agitator in two successive positions. From one position to the next, the agitator 122 is shown having rotated 10 degrees clockwise and its centre 126 having moved around one twelfth of the circular path (i.e. 30 degrees around) in the opposite direction (anticlockwise). Similarly, Figure 8 shows the agitator 122 in the same position as shown in Figure 6, together with five further images of the agitator 122 in five such successive positions. Figure 9 shows 12 positions in total, equating to the agitator 122 having performed a third of a complete rotation and its centre having moved around the circular path 132 once. Only the arrows for the first and twelfth agitator positions are shown in Figure 9, to assist in seeing the first (arrow 134) and last (arrow 140) positions of the agitator 122 for the first third of a complete cycle.

From Figures 6 to 9, and Figure 9 in particular, it will be seen that the first pointed region of the agitator 122 has moved from the top left corner of the notional square 136, has traced along the top edge, has reached into the top right corner of the square, without quite touching the vertex of the square 136, and has progressed about a third of the way -12 -down the right hand side. The other vertices of the agitator 122 have progressed along the remaining outline of the square, and have reached into the other corners of the square. The curved edges of the agitator also sweep out an area that extends very close to, if not touching, the edge of the square. The notional square 136 is drawn to be the smallest square that contains the area swept out by the movement of the agitator 122, without any part of that area extending beyond the square. It will be seen that vast majority of the area of the notional square is covered. In this embodiment it is believed that al leash aboui 95% of the area of the notional square 136 is swept out by the movement of the agitator 122.

As shown in Figure 5, two agitators 122 are provided side by side, each sweeping out a generally square shape, the square shapes sharing a common boundary 130 (the broken line shown in Figure 5) such that the two agitators together sweep over a generally oblong area. Such a square edged area of coverage allows for effective cleaning in the corners of a room.

Figure 10 illustrates a second embodiment which differs from the first embodiment primarily in the positioning of the agitators 222 in relation to the flexible outer skirt 216. The pair of agitators 222 side by side sweep out an area that is oblong in shape and contained with the rectangular broken line 224 shown in Figure 10. This rectangle 224 lies within the planform of the area surrounded by the base of the skirt 216, such that as each driven agitator moves through a complete cycle of movement it does not come into contact with the skirt, when the skirt is in its neutral position. The skirt 216 is arranged around the perimeter of the cleaner head 214 so that the skirt provides a barrier between the side edge of the agitator 222 and any external objects or vertical surfaces that the cleaner head 214 comes into contact with. The flexible outer skirt 216 extends down towards the surface to be cleaned such that in use it is just able to make contact with the floor. When the cleaner head 214 is pressed against two perpendicular walls during use (e.g. a corner of a room) the flexible outer skid 216 will be deformed inwardly such that it is pressed in more tightly against the floor and it may make contact with the agitators 222. The skirt will create a partial seal against the floor, allowing an increased level of vacuum suction into the corner. This aids in the collection of the dust and debris that has been agitated by the agitators. When the skirt 216 is forced into contact with one of the agitators 222 it will deform and allow the agitator to continue moving along its driven path. The agitator may thus be urged into closer proximity with a wall or corner than would be possible with a non-deformable skirt or hard-shelled housing with no skirt.

-13 -Whilst the present invention has been described and illustrated with reference to particular embodiments, it will be appreciated by those of ordinary skill in the art that the invention lends itself to many different variations not specifically illustrated herein. By way of example only, certain possible variations will now be described.

The agitators which are described in the first embodiment as being constantly in contact with the skirt, could instead make contact with the skirt at least once during each complete cycle of movement. This would allow the skirt to return to its neutral position when not exposed to any force from the agitators.

It may be beneficial in certain embodiments for the flexible skirt to extend around, partly or wholly, each agitator separately. There may for example be a separate flexible skirt associated with each agitator.

Where in the foregoing description, integers or elements are mentioned which have known, obvious or foreseeable equivalents, then such equivalents are herein incorporated as if individually set forth. Reference should be made to the claims for determining the true scope of the present invention, which should be construed so as to encompass any such equivalents. It will also be appreciated by the reader that integers or features of the invention that are described as preferable, advantageous, convenient or the like are optional and do not limit the scope of the independent claims. Moreover, it is to be understood that such optional integers or features, whilst of possible benefit in some embodiments of the invention, may not be desirable, and may therefore be absent, in other embodiments.

Claims

-14 -Claims 1. 2. 3. 4. 5. 6. 7.A cleaner head for a vacuum cleaner, the cleaner head comprising: a. an airflow path for providing suction to a surface to be cleaned, b. a housing, c. at least one driven agitator for engaging the surface to be cleaned and being mounted within the housing, and d. an outer skid arranged around the perimeter of the housing and arranged to be able to contact the surface to be cleaned during use, wherein the outer skirt is sufficiently flexible such that it is able to contact and be deformed by the agitator during use.
A cleaner head for a vacuum cleaner according to claim 1, wherein the agitator is arranged to be driven relative to the cleaner head in a plane.
A cleaner head for a vacuum cleaner according to claim 2, wherein the agitator is arranged to be driven relative to the cleaner head so that it rotates in one direction about a moving axis which moves around a path in an opposite direction.
A cleaner head for a vacuum cleaner according to claim 3, wherein the agitator is so arranged that the moving axis is moved around a closed path in cycles at a frequency which is higher than the frequency of rotation of the agitator.
A cleaner head for a vacuum cleaner according to either of claims 3 and 4, wherein the agitator is so arranged that the path around which the moving axis moves is a round path.
A cleaner head for a vacuum cleaner according to any preceding claim, wherein the agitator has a substantially triangular planform.
A cleaner head for a vacuum cleaner according to any preceding claim, wherein the agitator comprises multiple bristles.
-15 - 8. A cleaner head for a vacuum cleaner according to any preceding claim, wherein the cleaner head comprises a pair of driven agitators in the housing which are configured to move within an oblong envelope of movement.
9. A cleaner head for a vacuum cleaner according to any preceding claim, wherein the housing of the cleaner head has an oblong planform shape.
10. A cleaner head for a vacuum cleaner according to any preceding claim, wherein the outer skirt extends to provide a protective barrier around the agitator during use.
11. A cleaner head for a vacuum cleaner according to any preceding claim, wherein the outer skirt is made of a resilient material, such that it is able to be deformed and then return to a neutral position.
12. A cleaner head for a vacuum cleaner according to claim 11, wherein when the outer skirt is in its neutral non-deformed position it always intersects the path of the agitator at least once during a complete cycle of movement of the agitator.
13. A cleaner head for a vacuum cleaner according to claim 11, wherein when the outer skirt is in its neutral non-deformed position it does not intersect the path of the agitator during a complete cycle of movement of the agitator.
14 A cleaner head for a vacuum cleaner according to any of claims 11 to 13, wherein the skirt is so configured that an external force which causes a first portion of the skirt to move inwardly from the perimeter of the planform shape of the skirt when in its neutral position will also cause a second portion of the free end of the skirt to move outwardly from the perimeter of that planform shape, thus enabling the skirt to adopt a shape which conforms more closely to the shape of an object against which the skirt is pushed.
15. A cleaner head for a vacuum cleaner according to any preceding claim, wherein the outer skirt extends from the housing and terminates at a free end which defines a closed loop.
16. A vacuum cleaner head comprising: a housing, a driven agitator for engaging a surface to be cleaned and being mounted within the housing, arid a resilient outer skirt arranged around the perimeter of the housing, wherein the resilient outer skirt has a neutral position which the outer skirt reverts to when not deformed by an external force, the outer skirt extending from the housing and terminating at a free end which defines a first planform shape when the skirt is in its neutral position, and wherein the skirt is so configured that an external force which causes a first portion of the free end of the skirt to move inwardly from the perimeter of the first planform shape is able to cause a second portion of the free end of the skirt to move outwardly from the perimeter of the first planform shape, thus enabling the free end of the skirt to adopt a second planform shape which conforms more closely to the shape of an object against which the skirt is pushed than the first planform shape.
17. A vacuum cleaner having a cleaner head according to any preceding claim. 20