BRUSH ASSEMBLY FOR A FLOOR CLEANING APPARATUS

Abstract

A vacuum cleaner is described and comprises a handle portion and a housing containing a collection apparatus for removing contaminants from an airstream. Base portion has a suction inlet arranged to draw air into the base portion. At least one, and preferably two brush assemblies are rotatably mounted to the underside of base portion. Each brush assembly comprises a body portion around the circumference of which a plurality of bristles, preferably clumped in bristle tufts are mounted. On the underside of each body portion, a plurality of floor engaging members are disposed. Floor engaging members are configured to engage a surface on which the vacuum cleaner is placed such that when the vacuum cleaner is advanced forward, the floor engaging members grip the surface to cause rotation of the body portion and therefore brush assemblies.

Claims

1. A brush assembly for a floor cleaning apparatus, the brush assembly comprising: a body portion rotatably mountable to an underside of a floor cleaning apparatus; a plurality of bristles disposed around the edge of the body portion, said plurality of bristles being configured to engage a surface to be cleaned; and a plurality of floor engaging members projecting from the underside of the body portion, each said floor engaging member being capable of frictionally engaging the surface on which the brush assembly is disposed to cause rotation of the body portion as the brush assembly is moved along said surface.

2. The brush assembly according to claim 1, wherein each said floor engaging member comprises an elastomeric finger.

3. The brush assembly according to claim 1, wherein a longitudinal axis of each said floor engaging member is non-perpendicular to the underside of said body portion.

4. The brush assembly according to claim 1, further comprising bearing means arranged to allow rotation of said brush assembly in a first direction, but prevent rotation of said brush assembly in a second direction, opposite to said first direction.

5. The brush assembly according to claim 1, wherein the axis of rotation of the body portion is non-parallel to said surface.

6. A vacuum cleaner comprising: a handle portion; a collection apparatus for removing contaminants from an airstream; a base portion configured to be moved along a surface to collect contaminants therefrom, the base portion comprising a suction inlet; and at least one brush assembly rotatably mounted to the underside of said base portion, wherein an axis of rotation of said at least one brush assembly is arranged such that a first side of said at least one brush assembly closest to said suction inlet is tilted towards the surface and a second side of said at least one brush assembly, opposite said first side, is tilted away from said surface.

7. The vacuum cleaner according to claim 6, further comprising a bearing means arranged to allow rotation of said at least one brush assembly in a first direction, but prevent rotation of said at least one brush assembly in a second direction, opposite to said first direction.

8. The vacuum cleaner according to claim 6, wherein the axis of rotation of the at least one brush assembly is non-parallel to the surface.

9. The vacuum cleaner according to claim 6, wherein the axis of rotation of said at least one brush assembly is arranged such the axis is tilted forwardly and towards a front edge of the base portion.

10. A vacuum cleaner comprising: a handle portion; a collection apparatus for removing contaminants from an airstream; a base portion configured to be moved along a surface to collect contaminants therefrom, the base portion comprising a suction inlet and a front edge; and at least one brush assembly rotatably mounted to the underside of said base portion, wherein an axis of rotation of said at least one brush assembly is tilted forwardly and towards the front edge.

11. The vacuum cleaner according to claim 10, wherein the axis of rotation of said at least one brush assembly is arranged such that a first side of said at least one brush assembly closest to said suction inlet is tilted towards the surface and a second side of said at least one brush assembly, opposite said first side, is tilted away from said surface.

12. The vacuum cleaner according to claim 10, wherein said at least one brush assembly comprises: a body portion; a plurality of bristles disposed around the edge of the body portion, said plurality of bristles being configured to engage the surface; and a plurality of floor engaging members projecting from the underside of the body portion, each said floor engaging member being capable of frictionally engaging the surface to cause rotation of the body portion as the brush assembly is moved along said surface.

13. The vacuum cleaner according to claim 12, wherein each said floor engaging member comprises an elastomeric finger.

14. The vacuum cleaner according to claim 12, wherein a longitudinal axis of each said floor engaging member is non-perpendicular to the underside of said body portion.

15. The vacuum cleaner according to claim 10, further comprising bearing means arranged to allow rotation of said at least one brush assembly in a first direction, but prevent rotation of said at least one brush assembly in a second direction, opposite to said first direction.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Embodiments of the present invention will now be described by way of example only, and not in any limitative sense, with reference to the accompanying drawings in which:

[0037] FIG. 1 is a perspective view of the front of an upright vacuum cleaner comprising a brush assembly embodying the present invention;

[0038] FIG. 2 is a view of the underside of the vacuum cleaner of FIG. 1;

[0039] FIG. 3 is a top view of the base portion of the vacuum cleaner of FIG. 1 shown moving forwardly;

[0040] FIG. 4 is a top view of the base portion of the vacuum cleaner of FIG. 1 shown moving rearwardly;

[0041] FIG. 5 is a front view of the base portion of the vacuum cleaner of FIG. 1;

[0042] FIG. 6 is a view of the underside of the vacuum cleaner of FIG. 1;

[0043] FIG. 7 is a cross-sectional view of one side of the base portion of the vacuum cleaner of FIG. 1 viewed from the front;

[0044] FIG. 8 is a partial cross-section of the base portion of the vacuum cleaner of FIG. 1 viewed from the side;

[0045] FIG. 9 is a partial cross-section of the base portion of the vacuum cleaner of FIG. 1 viewed from the side;

[0046] FIG. 10 is a front perspective view of the base portion of the vacuum cleaner of FIG. 1; and

[0047] FIG. 11 is a view from the top of one side of the base portion of the vacuum cleaner of FIG. 1.

DETAILED DESCRIPTION

[0048] The following describes a vacuum cleaner with a brush assembly for agitating dirt and other contaminants on a surface to be cleaned. Although the following description relates to a vacuum cleaner, the brush assembly can be implemented on other types of floor cleaning apparatuses, such as a sweeper or a steam mop.

[0049] Referring to FIGS. 1 and 2, a vacuum cleaner 2 comprises a handle portion (not shown) and a housing 4 containing a collection apparatus for removing contaminants from an airstream. Types of collection apparatus will be familiar to persons skilled in the art. For example, the collection apparatus for separating contaminants from the airstream could take the form of a cyclone separator, a filter bag, or a combination of cyclone separator and filter arrangements.

[0050] Vacuum cleaner 2 also comprises a base portion 6 having a suction inlet 8 arranged to draw air into the base portion 6 on operation of the motor (not shown) of the vacuum cleaner 2. At least one, and preferably two brush assemblies 10 are rotatably mounted to the underside of base portion 6. Each brush assembly 10 comprises a body portion 12 around the circumference of which a plurality of bristles 14, preferably clumped in bristle tufts are mounted. On the underside of each body portion 12, a plurality of floor engaging members 16 are disposed. Eight floor engaging members are shown spaced equiangularly from the centre of the body portion 12, although more or less floor engaging members could be used depending on the size of the body portion 12. Floor engaging members 16 are configured to engage a surface on which the vacuum cleaner 2 is placed such that when the vacuum cleaner is advanced forward, the floor engaging members 16 grip the surface to cause rotation of the body portion 12 and therefore brush assemblies 10. In a preferred embodiment, each floor engaging member comprises a finger. For example, each finger could be made from rubber or another elastomeric polymer or another suitable material such as a plastic.

[0051] Referring to FIGS. 5 to 7, each brush assembly 10 (shown without bristles for clarity) comprises a shaft 18 keyed to the body portion 12 to enable the body portion 12 to be rotatably mounted to the base portion 6 of the vacuum cleaner 2. Shaft 18 is disposed non-rotatably in one-way bearing 20 which permits rotation in only one direction as will be further explained below. Referring to FIG. 7, the axis of rotation R is offset from the vertical Y by an angle such that a first side 10a of the brush assembly closest to suction inlet 8 is tilted towards a surface S on which the vacuum cleaner is disposed. In this configuration, the second side 10b opposite first side 10a of the brush assembly 10 is tilted away from surface S such that elastomeric fingers 16 are out of contact with the surface S on the second side 10B. Preferably, angle is between 2 and 10 degrees and, more preferably, between 3 and 6 degrees. In particular, an angle between 4 and 5 degrees has been found to be optimal for providing a large contact zone for the brush and the rubber fingers, as shown in FIG. 10.

[0052] It can also be seen in FIG. 7 that each elastomeric finger 16 is mounted non-perpendicularly to a plane P defined by body portion 12. This ensures that the ends of elastomeric fingers 16 make the best contact with surface S. Alternatively, each finger 16 could be mounted perpendicularly to plane P for ease of manufacture. Referring to FIG. 5, it can be seen that both brush assemblies 10 are mounted on axes of rotation that are non-parallel to the vertical axis of body portion 6 such that sides 10a of the brush assemblies 10 closest to suction inlet 8 are tilted towards surface S. Also, the axes of rotation of the brush assemblies are non-parallel to the surface S and to the horizontal axis of the body 6.

[0053] Referring to FIGS. 8 and 9, shaft 18 and one-way bearing 20 are also arranged such that the part of each brush assembly 10 forward of the shaft 18 is tilted towards the surface S. This is achieved by tilting the axis of rotation of the brush assembly, which runs longitudinally along the shaft 18, forwardly and towards the front edge 6a. As shown, the part projecting forwardly of the front edge 6a of base portion 6 is tilted towards the surface S on which the vacuum cleaner 2 is disposed. In other words, an angle is formed between a horizontal axis X of the body portion and the plane of rotation of the brush assembly 10. Preferably, angle is between 1 and 4 degrees and, more preferably between 2 and 3 degrees. This provides an optimal contact area forward of the front edge whilst preventing the brush from digging too deep into carpet when the vacuum cleaner is pushed forwardly.

[0054] Referring to FIGS. 10 and 11, due to the angular offset of the axis of rotation R of each brush assembly 10, only the bristles 14 and around the region forwardly of the shaft 18 and closest to suction inlet 8 are in contact with the floor in normal use. Also referring to FIGS. 5 and 6, due to the angular offset of the axis of rotation R of each brush assembly 10, only the fingers 16 closest to suction inlet 8 are in contact with the floor in normal use.

[0055] Referring to FIGS. 2, 3, 4 and 11, operation of vacuum cleaner 2 and brush assemblies 10 will now be described. When the vacuum cleaner 2 is pushed forwardly in the direction of arrow A of FIG. 3, elastomeric fingers 16 in the zone of contact with the floor closest to suction inlet 8 grip the floor and cause rotation of the brush assemblies 10. This rotation is in the clockwise sense for the left hand brush assembly 10 of FIG. 3 and in the anti-clockwise sense for the right hand brush assembly of FIG. 3. This causes dust in the area where the bristles cotact the floor to be flicked towards the suction inlet. Since the bristles 14 on the outer sides of base portion 6 are raised away from the floor, no contact is made such that dust and other contaminants are not flicked away from the base portion 6.

[0056] When the base portion 6 is pulled rearwardly in the direction of arrow B of FIG. 4, the one-way bearing 20 of each brush assembly 10 prevents rotation which therefore prevents dust being flicked away from the suction inlet 8. On further advancement of the vacuum cleaner 2 in the direction of arrow A, brush assemblies 10 will continue to rotate.

[0057] It has been found that projecting fingers 16 are effective on various thicknesses of carpet as well as hard floors to provide improved drive of the brush assemblies 10 when compared with use of a continuous ring of frictionally engaging material. Improved cleaning has also been found resulting from prevention of rotation of the brush assemblies on a rearward stroke.

[0058] It will be appreciated by persons skilled in the art that the above embodiments have been described by way of example only and not in any limitative sense, and that various alterations and modifications are possible without departure from the scope of the invention as defined by the appended claims.