Vacuum cleaning utensil having rotating brush

Abstract

A vacuum cleaning utensil has a brush arranged for rotating about a substantially vertical axis. Further, the vacuum cleaning utensil has a guide for pushing the brush towards a surface to be cleaned during only a part of the rotation of the brush. During another part of the rotation, the brush is released from the surface to be cleaned.

Claims

1. A vacuum cleaning utensil having a brush arranged for rotating about a substantially vertical axis, wherein the vacuum cleaning utensil is provided with a guide for pushing the brush towards a surface to be cleaned during only a part of the rotation of the brush, the brush being arranged for being released from the surface during another part of the rotation.

2. The vacuum cleaning utensil as claimed in claim 1, wherein the guide has a height that varies along a circumference of the guide so as to define the part of the rotation where the brush is pushed towards the surface.

3. The vacuum cleaning utensil as claimed in claim 1, wherein the guide is arranged for pushing the brush towards the surface where the brush is facing away from a suction mouth, the brush being arranged for being released from the surface where the brush is facing the suction mouth.

4. The vacuum cleaning utensil as claimed in claim 1, wherein a height of the guide, or at least a part of the guide that pushes the brush most towards the surface, is between 5 and 15 mm, preferably not exceeding 10 mm.

5. The vacuum cleaning utensil as claimed in claim 1, wherein the brush is mounted at an angle with respect to the vertical axis.

6. The vacuum cleaning utensil as claimed in claim 5, wherein the angle is between 5 and 30 degrees, and preferably between 15 and 25 degrees.

7. A vacuum cleaner provided with a nozzle formed by the vacuum cleaner utensil as claimed in claim 1.

8. A robot vacuum cleaner formed by the vacuum cleaning utensil as claimed in claim 1.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 shows an embodiment of a vacuum cleaner utensil in accordance with the invention; and

(2) FIG. 2 shows a bottom view of a robot vacuum cleaner in accordance with the present invention.

DESCRIPTION OF EMBODIMENTS

(3) FIG. 1 shows an embodiment of a vacuum cleaner utensil in accordance with the invention, which may be used in the context of a robot vacuum cleaner RVC having a (side) brush assembly BA having at least one rotating brush B, or in the context of a vacuum cleaner nozzle having such a (side) brush assembly BA. In this embodiment, the brush assembly BA is mounted substantially vertically, a brush axis A being at a non-zero angle α with respect to the vertical. In an embodiment, this angle α may be between 5 and degrees 30, and is preferably between 15 and 25 degrees, such as about 20 degrees. As a result, at a right-hand end, which would be at an outer edge of the vacuum cleaner, dirt is wiped from a surface S to be cleaned (e.g. a floor), while at a left-hand end, dirt is released from the brush B, where the dirt can be sucked up by a dirty air inlet (i.e. a suction mouth M) of a vacuum cleaner (nozzle).

(4) An advantage of mounting the brush assembly BA at the angle α with respect to the vertical, is that by letting the brush B lose its connectivity with the surface S, it is possible to create a moment for the dirt to escape the rotational movement of the brush B. At this point the vacuum cleaner (nozzle) will be able to suck up the dirt. This results in a more efficient vacuum cleaner (nozzle).

(5) In accordance with the invention, the vacuum cleaner utensil is provided with a guide G, e.g. a cam or rim at the bottom, which will help to better control the brush B. Without the guide G, the operation of the brush B is not optimized, as the brush B can be in contact with the surface S and free from the surface S at different places, so that the area where the brush B sweeps the surface S cannot be optimized. Just mounting the brush assembly BA at an angle with respect to the vertical does not yet give full control over at which part of the rotational movement of the brush the brush B is touching the surface S. Nor can it define accurately where the brush B is lifted or how ‘quick’ the brush is lifted from the surface S to be cleaned. The geometry of the guide G provided by the present invention provides that full control and thus does give an advantage in efficiency and effectiveness.

(6) The guide G could bring the effect also without the brush axis A being mounted at a non-zero angle α with respect to the vertical (e.g. when the brush hairs B are mounted in such a way on the brush assembly BA that they only touch the surface S to be cleaned as a result of the guide G pushing them towards the surface S), but doing so would increase the deflection of the brush hairs B in the lower position, causing higher friction, wear and reduced lifetime. Besides that there is also an increased risk for brush deformation, so that part of the brush hairs B could remain deflected in the lower position causing the lifting effect to be reduced. So, in a preferred embodiment, the guide G is present in combination with the brush axis A being at a non-zero angle α with respect to the vertical.

(7) FIG. 2 shows a bottom view of a robot vacuum cleaner RVC in accordance with the present invention. The robot vacuum cleaner RVC has three wheels W, two brush assemblies BA each having three brushes B, and a suction mouth M that functions as an inlet for dirty air. In accordance with this embodiment of the invention, at each brush assembly BA the bottom of the robot vacuum cleaner RVC is provided with a round guide G that pushes the brush B downwards towards the surface to be cleaned S at an outer edge of the robot vacuum cleaner RVC. In an embodiment, at that part of the guide G (i.e. at the outer edge of the robot vacuum cleaner RVC), its height is between 5 and 15 mm, preferably not exceeding 10 mm. The height of the guide G is lower at a side of the guide G directed towards the suction mouth M, so that there the brush B is released from the surface to be cleaned S so that dirt can leave the brush B and be sucked up at the suction mouth M.

(8) Embodiments of the invention thus provide a vacuum cleaning utensil having a brush B arranged for rotating about a substantially vertical axis A, and a guide G for pushing the brush B towards a surface S to be cleaned during a part of the rotation of the brush B. Preferably, the guide G has a height that varies along a circumference of the guide G so as to define the part of the rotation where the brush B is pushed towards the surface S, preferably at a part of the rotation where the brush B is directed away from a suction mouth M. A height of the guide G, or at least a part of the guide G that pushes the brush B most towards the surface S, may be between 5 and 15 mm, preferably not exceeding 10 mm. Preferably, the brush B is mounted at an angle α with respect to the vertical, which angle α may be between 5 and 30 degrees, and is preferably between 15 and 25 degrees. A vacuum cleaner is advantageously provided with a nozzle formed by such a vacuum cleaner utensil. A robot vacuum cleaner RVC is advantageously formed by such a vacuum cleaning utensil.

(9) It should be noted that the above-mentioned embodiments illustrate rather than limit the invention, and that those skilled in the art will be able to design many alternative embodiments without departing from the scope of the appended claims. For example, instead of a round guide G having a varying height as described above in relation to FIG. 2, it is possible to have a guide G that is only present at the part of the rotation where it is desired to push the brush B towards the surface to be cleaned S. The brush assembly BA may have one or more discrete brushes B as shown in FIG. 2, or a single brush B around its circumference. In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. The word “comprising” or “having” does not exclude the presence of elements or steps other than those listed in a claim. The word “a” or “an” preceding an element does not exclude the presence of a plurality of such elements. In the device claim enumerating several means, several of these means may be embodied by one and the same item of hardware. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage.