VACUUM CLEANER BRUSH ROLL

Abstract

An autonomous cleaning robot having a body, a driving means configured to move the robot in a forward direction over a surface being cleaned, a suction opening arranged at an underside of the body, and a roller arranged at the underside of the body and in front of the suction opening, relative the forward direction. The roller is configured to define a front air passageway at the surface, and comprises bristles arranged to form a front air barrier restricting an air flow in the front air passageway. The front air barrier is configured to be substantially uniform over an entire turn of the roller, wherein the bristles are further arranged to direct the air flow towards a particle passing by the roller, and further into the suction opening.

Claims

1. An autonomous cleaning robot, comprising: a body; a driving means configured to move the robot in a forward direction over a surface being cleaned; a suction opening arranged at an underside of the body; and a roller arranged at the underside of the body and in front of the suction opening, relative the forward direction; wherein: the roller is configured to define a front air passageway at the surface being cleaned; and the roller comprises bristles arranged to form a front air barrier restricting an air flow in the front air passageway, the front air barrier being configured to be substantially uniform over an entire turn of the roller, wherein the bristles are further arranged to direct the air flow towards a particle passing by the roller, and further into the suction opening.

2. The autonomous cleaning robot according to claim 1, wherein the bristles are distributed such that the number of bristles pointing towards the surface are distributed over a length portion of the roller corresponding to at least 50% of a total length of the roller.

3. The autonomous cleaning robot according to claim 1, wherein the bristles are uniformly distributed over substantially an entire envelope surface of the roller.

4. The autonomous cleaning robot according to claim 1, wherein the bristles are arranged with a density of 1 000-20 000 bristles per cm.sup.2.

5. The autonomous cleaning robot according to claim 1, further comprising a sealing edge arranged behind the suction opening, relative the forward direction, and configured to be spaced from the surface so as to define a rear air passageway between the surface and the sealing edge.

6. The autonomous cleaning robot according to claim 5, wherein the sealing edge is arranged such that a flow resistance of the rear air passageway is higher than a flow resistance of the front air passageway.

7. The autonomous cleaning robot according to claim 5, wherein a clearance between the surface and the sealing edge is smaller than, or equal to, a clearance between the surface and the body in front of the suction opening, relative the forward direction.

8. The autonomous cleaning robot according to claim 7, wherein the clearance between the sealing edge and the surface is 0-7 mm.

9. The autonomous cleaning robot according to claim 1, further comprising a roller housing having an inner surface, wherein the inner surface is arranged to partly surround the roller, along a portion of the roller facing away from the surface being cleaned, to form an upper air passageway with the roller, the upper air passageway having a higher flow resistance than the front air passageway.

10. The autonomous cleaning robot according to claim 1, wherein the roller is rotatable such that a portion of its envelope surface facing the surface to be cleaned is moved towards the suction opening.

11. The autonomous cleaning robot according to claim 1, wherein: the bristles protrude from a surface of a core of the roller, the core has a diameter in the range of 8-40 mm, and the bristles have a length in the range of 3-15 mm.

12. The autonomous cleaning robot according to claim 1, wherein the roller is arranged in the front third of the body, as seen in the forward direction.

13. (canceled)

14. The autonomous cleaning robot according to claim 11, wherein the core has a diameter in the range of 15-25 mm.

15. The autonomous cleaning robot according to claim 11, wherein the bristles have a length in the range of 3-10 mm.

16. The autonomous cleaning robot according to claim 11, wherein the bristles have a length in the range of 3-7 mm.

17. The autonomous cleaning robot according to claim 1, wherein the bristles are arranged with a density of 10 000-18 000 bristles per cm.sup.2.

18. The autonomous cleaning robot according to claim 1, wherein the bristles are arranged with a density of 12 000-17 000 bristles per cm.sup.2.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The above, as well as additional objects, features and advantages of the present inventive concept, will be better understood through the following illustrative and non-limiting detailed description of embodiments. Reference will be made to the appended drawings, on which:

[0019] FIG. 1 illustrates a top view of an autonomous cleaning robot according to an embodiment;

[0020] FIG. 2 is a cross section of an autonomous cleaning robot according to an embodiment;

[0021] FIG. 3 is a cross section of a roller of an autonomous cleaning robot according to an embodiment; and

[0022] FIG. 4 is a perspective view of a roller of an autonomous cleaning robot according to an embodiment.

[0023] Like reference numerals are used for like elements on the drawings. Unless otherwise indicated, the drawings are schematic and generally not to scale.

DETAILED DESCRIPTION OF EMBODIMENTS

[0024] FIG. 1 is a top view of an autonomous cleaning robot 100 for household use according to an embodiment, comprising a body 110, a driving means 120, 121, a suction opening (not shown), a suction unit 112 and a roller 140. The body 110 may form a chassis having an outer cover for protecting and enclosing functional units, such as control electronics, dust box and fan unit, arranged in the interior of the robot. Further, the chassis may provide support for the driving means 120, which in the present example is represented by two driving wheels 120 and a support wheel 121 arranged at the underside of the chassis. The driving of the drive wheels 120 may be performed by separate motors for improved navigation and movement control.

[0025] The roller 140 may be arranged at the underside of the chassis, and such that it engages a surface of the floor during operation. Preferably, the roller 140 is arranged in the front third of the body, as seen in the forward direction. The roller 140 may comprise a core and a plurality of bristles, which will be described in more detail in connection with the following figures.

[0026] During operation, the robot 100 may move autonomously over the surface to be cleaned, and preferably in a forward direction indicated by the arrows in FIGS. 1 and 2. When moving in the forward direction, debris, dust and other particles may be engaged by the bristles of the roller 140 and sucked into the interior of the robot 100 by means of an airflow that is passing over the surface. The roller 140 may preferably rotate in the same direction as the wheels 120, and with a speed that allows the bristles to brush the particles towards the suction opening 132 in the body 110 of the robot 100.

[0027] FIG. 2 is a cross section of a cleaning robot 100 according to an embodiment, which may be similarly configured as the cleaning robot discussed in connection with FIG. 1. Thus, the robot 100 may comprise a body, or chassis 110, accommodating a suction unit 112 for generating a suction airflow and filtering out dust and particles from the same. The suction airflow passes through the suction opening 132 and into the suction channel 130, leading into the interior of the robot 100. The suction opening 132 may be arranged at least slightly behind the roller 140 as seen in the forward travel direction indicated by the arrow.

[0028] In connection with the suction opening 132, and at the underside of the chassis 110, the roller 140 may be arranged for facilitating transport of dust and particles into the suction channel 130. The roller 140 may comprise an air impermeable core 144, which may be substantially cylindrical, onto which a plurality of bristles 142 may be attached. The bristles 142 may be attached with one end to the core such that the other end points away from the core 144, along a radial direction of the roller 140. The bristles may be arranged to form an air barrier that restricts the air flow in a front air passageway F between the core 144 and the surface. Preferably, the roller 140 is arranged to engage the floor surface during operation, such that the air in the front air passageway passes through the bristles 142 on its way towards the suction channel 130. By arranging the bristles 142 sufficiently dense in terms of number of bristles per unit area, a sealing against the surface may be accomplished that prevents a substantial amount of air from passing through the front air passageway F.

[0029] The chassis 110 may further comprise a sealing edge 150 arranged at the underside of the chassis 110 and behind the suction opening 132, relative the forward direction. The sealing edge 150 may be provided to reduce a clearance between the chassis 110 and the surface and thereby define a rear air passageway R for the air entering the suction opening 132 and passing towards the suction channel 130. Preferably, the clearance between the chassis 110 and the surface is smaller behind the roller 140 than in front of the roller 140, to provide a flow resistance in the rear air passageway R that is higher than in the front air passageway F. The clearance behind the roller 140 may for example be 0-7 mm. In an example, the sealing edge 150 is arranged to abut the surface to provide a flow resistance in the rear air passageway R that is higher than in the front air passageway F and hence force most of the air passing into the interior of the robot 100 to pass through the front air passageway F rather than the rear air passageway R.

[0030] A further air passageway may be defined at the upper side of the roller 140. This air passageway may hence be referred to as an upper air passageway U, and may be defined between an inner surface of a roller housing 160. The flow resistance along the upper air passageway U may be increased by increasing the length of the passageway and/or reducing a spacing between the inner surface and the roller 140. It is advantageous to use an upper air passageway that has a higher flow resistance than the front air passageway F, which allows it to restrict most of the airflow to the front air passageway F and thereby force the flowing air towards the surface to be cleaned.

[0031] FIG. 3 is a cross section of a roller according to an embodiment, which may be similarly configured as the embodiments discussed above in connection with FIGS. 1 and 2. The roller 140 may comprise a substantially cylindrical core 144 that can be mounted in the chassis such that it is rotatable around its length axis A, and spaced apart from the floor surface during operation. Further, the roller 140 comprises a plurality of bristles 142 arranged in a protruding manner on the air impermeable core 144. The bristles may be distributed such that the number of bristles that for a given point in time are directed towards the surface is constant. Further, as illustrated in the present figure, the bristles 142 may be evenly distributed along the length axis A of the core 144 such that the number of bristles pointing towards the surface are distributed along the entire length of the roller 140. In the present example, the bristles may be formed of nylon, polypropylene or hair.

[0032] The bristles 142 may be arranged such that they give way for a particle P passing under the roller 140. More specifically, the bristles 142 may be bent or pushed aside by the particle P such that an opening is formed in the barrier, allowing a flow of air to be directed towards the particle P and further into the suction opening. As indicated in the present figure, the particle P is small enough to pass through the gap defined by the clearance between the core 144 and the surface, and large enough to bend the bristles 142 to the side to create a local airflow through the barrier.

[0033] FIG. 4 is a perspective view of a roller 140 according to an embodiment, which may be similar to the embodiments described with reference to FIGS. 1 to 3. In the present example, the bristles 142 are distributed substantially uniformly over the entire roller 140, with the exception of one or several helical regions 146 wound around the length axis A of the roller 140. The helical region 146 forms a local gap in the air barrier, which due to the helical arrangement moves along the length axis A as the roller 140 rotates. The gap may for example be provided in order to provide a slight increase in the air flow through the front air channel. It may be desired to increase the air flow depending on the characteristics of the surface and to reduce the friction generating vacuum between the robot and surface.

[0034] The person skilled in the art is by no means limited to the example embodiments described above. On the contrary, many modifications and variations are possible within the scope of the appended claims. Additionally, variations to the disclosed examples can be understood and effected by the skilled person in practising the claimed inventive concept, from the study of the drawings, the disclosure, and the appended claims. 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.