Cleaning robot with side brush

Abstract

A cleaning robot (100) for cleaning a floor surface comprises a side brush (130) rotatable about a rotational axis (135) extending in a vertical direction. The side brush (130) has at least one radially projecting brush arm (145), wherein a radially outer section (155) of the brush arm (145) is flexible. A method (600) for cleaning a side brush (130) of such a cleaning robot (100) comprises the steps of determining (605) a cleaning requirement of the side brush (130); and of abruptly accelerating or decelerating (610, 615) the brush arm (145) about the rotational axis (135).

Description

[0001] The present invention relates to a cleaning robot for cleaning a floor surface. In particular, the invention relates to the cleaning of a side brush of such a cleaning robot.

[0002] A cleaning robot is designed to move across a floor surface in a home and clean it. Cleaning can be done, for example, by vacuuming or sweeping. The cleaning robot includes a side brush that rotates around a vertical axis. The side brush has at least one brush arm that, by rotating, moves across the floor surface to collect loose dirt.

[0003] Dirt that comes into contact with the brush arm tends to adhere to it. In particular, damp or greasy dirt can accumulate on the surface of the brush arm, or fibrous dirt can wrap around it. Such soiling can form a layer that is difficult to remove. Accumulated dirt can impede the cleaning action of the brush arm, and the rotation of the side brush can be restricted or even prevented by the dirt.

[0004] One of the problems underlying the present invention is to provide an improved technique for cleaning a brush arm of a side brush on a cleaning robot. The present invention solves this problem by means of the subject matter of the independent claims. Dependent claims describe preferred embodiments.

[0005] The invention relates to a cleaning robot with a side brush. The side brush is rotatable about an axis of rotation extending in a substantially vertical direction and comprises at least one radially projecting brush arm. At least one radially outer section of the brush arm is designed to be flexible. It is proposed to accelerate the brush arm during its rotational movement about the axis of rotation in such a way that it performs a whipping motion to fling off dirt that has accumulated on the brush arm.

[0006] According to a first aspect of the present invention, a method is proposed which includes steps of determining a cleaning requirement of the side brush; and of jerkily accelerating or decelerating the brush arm about the axis of rotation.

[0007] The cleaning requirement can be determined based on the use of the side brush to clean a floor surface. For example, a cleaning requirement can be determined after the side brush has rotated a predetermined number of times around its axis of rotation or after the side brush has rotated for a predetermined time. In another embodiment, the cleaning requirement can be determined based on the distance traveled by the cleaning robot. The cleaning robot can include a device for collecting dirt from the floor surface, and the cleaning requirement can be determined based on the amount of dirt collected. In yet another embodiment, a cleaning requirement can be determined when the rotational resistance of the side brush exceeds a predetermined level. A combination of several criteria can also be used to determine the cleaning requirement.

[0008] The side brush or brush arm can be driven by a drive unit, in particular an electric motor. Typically, the drive unit is controlled to gently accelerate the side brush when starting or to gently decelerate or coast to a stop when stopping. The proposed controlled, jerky acceleration or deceleration of the brush arm can set the radially outer section into oscillation, causing it to perform a whipping motion that flings dirt off. This whipping motion allows a section of the brush arm to reach a high speed, and high accelerations can be exerted on the radially outer section of the brush arm. Adhering dirt can thus be advantageously flung off or shaken off.

[0009] Preferably, the brush arm is repeatedly accelerated and decelerated in a predetermined sequence. This sequence can include rotational movements of varying speeds and / or angles of rotation. For example, the sequence can include oscillations with decreasing or increasing frequency or amplitude. This allows for particularly efficient removal of adhering dirt.

[0010] Due to its flexural elasticity, the brush arm exhibits a natural or resonant frequency. It is particularly preferred that the sequence is tuned to the resonant frequency of the brush arm. If the brush arm is excited at its natural frequency in alternating directions of rotation around the axis of rotation, a standing wave pattern can result. For example, it can be ensured that its radially outer end whips with maximum amplitude in the plane of rotation. By appropriately adjusting the excitation, it can also be achieved that the radially outer end remains essentially stationary, and large movements occur in a radially central section of the brush arm. The excitation frequency can be easily varied to account for the fact that the resonant frequency of the brush arm may be altered, for example, by damping at the floor surface or by adhering dirt.

[0011] The cleaning robot may include a suction nozzle. A blower may be configured to draw an airflow from the floor surface through the suction nozzle. It is preferred that the sudden acceleration or deceleration of the brush arm occurs in a predetermined rotational position of the brush arm relative to the suction nozzle.

[0012] The rotational position is preferably chosen so that dirt shaken off the brush arm can be easily picked up by the suction nozzle. If the side brush includes several brush arms, multiple cleaning cycles can be carried out in different rotational positions, with each cycle involving a different brush arm in the predetermined position relative to the suction nozzle.

[0013] According to a second aspect of the present invention, a cleaning robot for cleaning a floor surface is proposed. The cleaning robot comprises a centrifugal element that can be lowered into a movement area of ​​the radially outer region of the brush arm, so that the brush arm, during its rotational movement about the axis of rotation, runs against the lowered centrifugal element and the radially outer region of the brush arm performs a whipping motion.

[0014] The centrifugal element can be designed, for example, as a cylinder or a pin. Raising or lowering it can be easily achieved, for instance, by means of an electric motor or electromagnetic actuator. The centrifugal element can force the described whip-like motion of the brush arm as it rotates around its axis, thus cleaning the brush arm of adhering dirt. Cleaning the brush arm can be advantageously time-saving. A cleaning process of a floor surface by the cleaning robot is only interrupted very briefly to clean the brush arm. The cleaning result on the floor surface can be significantly improved.

[0015] The cleaning robot preferably comprises a drive unit configured to drive the brush arm on the side brush around the axis of rotation at a predetermined speed. The rotational speed is preferably selected such that the radially outer region of the brush arm is deflected against the direction of rotation at the spinning element until its radially outer boundary passes the spinning element and the radially outer region executes the whipping motion.

[0016] The drive unit preferably comprises an electric motor. More preferably, a brushless DC (BLDC) motor is used, whose speed, rotational position, and / or torque can be precisely determined or controlled. The drive unit can control a lower speed to clean the brush arm against the centrifugal element, or a higher speed to move the brush arm across the floor surface. A reverse speed assignment is also possible.

[0017] The cleaning robot preferably includes a suction nozzle. The suction nozzle is further preferably connected to a blower, which is configured to draw an airflow across the floor surface through the suction nozzle. The side brush is further preferably positioned relative to the suction nozzle such that the whipping motion of the brush arm occurs in the area of ​​the suction nozzle. In another embodiment, the whipping motion can occur at a distance from the suction nozzle, with the whipping direction, i.e., the direction in which dirt is flung off the brush arm, pointing towards the suction nozzle. Dirt shaken off the brush arm can thus be sucked directly into the suction nozzle.

[0018] In a further embodiment, in addition to the first centrifugal element described, a second centrifugal element is provided, which can be lowered into the area of ​​movement. The centrifugal elements are preferably arranged such that the brush arm, after sliding off the first centrifugal element, whips against the second centrifugal element. The distances between the centrifugal elements and the axis of rotation can be of similar size. The centrifugal effect can be enhanced by the second centrifugal element. In particular, an impulse can act on the radially outer section of the brush arm, which can dislodge adhering dirt particularly effectively. Both centrifugal elements can be raised or lowered by means of a common actuating device. Individual actuation is also possible. This allows for the generation of different whipping directions.

[0019] The centrifugal element can have a horizontal recess to position the brush arm in a predetermined vertical position. The recess can be designed as a horizontal notch or groove. The recess can have converging edges. Particularly when the brush arm comprises a number of horizontal fibers or hairs, the recess can provide vertical centering. Individual fibers can be more effectively bundled together. The notch also allows for the removal of dirt trapped between the fibers of the bundle.

[0020] According to yet another aspect of the present invention, a base station for a cleaning robot described herein comprises a centrifugal element which lies in a movement range of the radially outer region of the brush arm when the cleaning robot is in a predetermined parking position at the base station.

[0021] In this way, a known cleaning robot can be used with the technique proposed herein to clean the side brush of the cleaning robot. The cleaning robot can assume the parking position to, for example, recharge an electrical energy storage device, empty a dirt container, or take on operating fluid. The cleaning robot can be easily steered into the predetermined parking position. Due to the known position of the cleaning robot relative to the base station in the parking position, the spin element can be easily attached so that the described whipping effect occurs and the cleaning of the brush arm is successful.

[0022] In another embodiment, the spinning element can be lowered vertically out of or raised into the movement area. The spinning element can be moved, for example, by an electric motor or electromagnetically. The extendable / retractable spinning element can improve the cleaning robot's freedom of movement at the base station.

[0023] The invention will now be described in more detail with reference to the accompanying figures, in which: Figure 1 shows a cleaning robot; Figure 2 shows a side brush on a cleaning robot; Figure 3 shows the movement sequence of a side brush; Figure 4 shows a cleaning robot with a side brush in a further embodiment; Figure 5 shows a cleaning robot with a base station; and Figure 6 shows a flowchart of a process. represent.

[0024] Figure 1Figure 1 shows an exemplary cleaning robot 100 in a view of its underside. The cleaning robot 100 includes a motion control system, which is exemplified by two independently controllable drive wheels 105 and a guide wheel 110. The cleaning robot 100 is designed to move across a floor surface and clean it. For cleaning, a suction nozzle 115 is provided as an example, through which an airflow can be drawn in. Optionally, a brush roller 120 can be attached in the area of ​​the suction nozzle 115, which is preferably driven about a horizontal axis of rotation. Also optionally, one or more mopping pads 125 are provided, with which a wet cleaning of the floor surface can be carried out.

[0025] A side brush 130 is rotatably mounted about a vertical axis of rotation 135. A drive device for driving the side brush 130 about the axis of rotation 135 is provided in Figure 1Not visible. The side brush 130 comprises a hub 140 from which one or more brush arms 145 extend radially. The side brush 130 is preferably mounted on the cleaning robot 100 with respect to the suction nozzle 115 such that the axis of rotation 135, relative to a longitudinal or travel direction of the cleaning robot 100, is located laterally and in front of the suction nozzle 115. A brush arm 145 comprises a radially inner section 150 and a radially outer section 155. At least the radially outer section 155 is designed to be flexible. Optionally, the sections 150 and 155 can also be identical and, in particular, integrally formed.

[0026] It is proposed to provide a centrifugal element 160 within the range of motion of the brush arm 145 around the axis of rotation 135 on the cleaning robot 100. The centrifugal element 160 is preferably positioned such that the brush arm 145 runs against the centrifugal element 160 in a region between the inner section 150 and the outer section 155. More preferably, the centrifugal element 160 is vertically movable, and its vertical position can be controlled by a control device of the cleaning robot 100.

[0027] Figure 2 Figure 1 shows a side brush 130 on a cleaning robot 100. The illustrated embodiment corresponds to that of Figure 1The side brush 130 is attached to the cleaning robot 100 in such a way that a brush arm 145 on the spinner 160 can perform a whip-like movement to shake off dirt that has accumulated on the brush arm 145. For this purpose, the brush arm 145 on the spinner 160 can be deflected in the plane of rotation about the axis of rotation 135 in the opposite direction of its rotation until its radially outer limit passes the spinner 160. Due to the elasticity of the brush arm 145, it then performs a whip-like movement in the plane of rotation, whereby high accelerations can act on individual sections of the brush arm 145.

[0028] Figure 3 shows a movement sequence of a side brush 130. Figures 3a to 3d show the cleaning robot 100 from Figure 1 at successive time points during a cleaning process of a brush arm 145.

[0029] In Figure 3aA brush arm 145 moves towards the centrifugal element 160, rotating in a clockwise direction. Figure 3b The brush arm 145 is deflected backwards against the direction of rotation of the centrifugal element 160. Figure 3c A contact point between the brush arm 145 and the centrifugal element 160 has been reached at the outermost point of the brush arm 145. Figure 3d The brush arm 145 has detached from the centrifugal element 160 and performs a centrifugal movement due to its inherent elasticity.

[0030] In the illustrated embodiment, a brush arm 145, during its rotation about the axis of rotation 135, sweeps over a section of the suction opening 115. The whipping motion of a brush arm 145 that has slid off the centrifugal element 160 preferably occurs in such a way that any dirt detached during this process can be effectively picked up by the suction opening 115. In the illustrated embodiment, the whipping motion takes place below or in the area of ​​the suction opening 115.

[0031] Figure 4 Figure 1 shows a cleaning robot 100 with a side brush 130 in a further embodiment. In this embodiment, in addition to the spinning element 160, a further spinning element 405 is provided. The spinning element 160 can also be called the first spinning element and the spinning element 405 the second spinning element. Figures 4a and 4b show successive time points of a rotational movement of the side brush 130 on the cleaning robot 100.

[0032] In Figure 4a The brush arm 145 slides along the first centrifugal element 160 due to the rotational movement of the side brush 130. Figure 4bIt can be seen how the brush arm 145, after passing the first centrifugal element 160, strikes the second centrifugal element 405 due to its rotational movement and inherent elasticity. The resulting whip-like motion can already dislodge dirt from the brush arm 145. If the side brush 130 continues to rotate until the brush arm 145 disengages from the second centrifugal element 405, the action described above with reference to Figure 2 The described whipping motion occurs again and further dirt can be shaken off.

[0033] Figure 5 shows an example cleaning robot 100 with a base station 500. In Figure 5a The cleaning robot 100 moves towards the base station 500. In Figure 5bThe cleaning robot 100 has assumed a predetermined parking position at the base station 500. In this position, for example, electrical contacts between the cleaning robot 100 and the base station 500 may be closed.

[0034] A spin element 160 is attached to the base station 500 in such a way that it is positioned within the movement range of the brush arm 145, the side brush 130, and the cleaning robot 100. Figure 1 The spinner element 160 is located when the cleaning robot 100 has assumed the park position. Optionally, the spinner element 160 can be vertically adjustable. In the illustrated raised position, the spinner element 160 extends into the movement range of the brush arm 145; in a lowered position, the movement range can be cleared by the spinner element 160.

[0035] Figure 6 shows a flowchart of an exemplary procedure 600 for controlling a cleaning robot 100 according to Figure 1 .

[0036] In step 605, the cleaning requirement of a brush arm 145 of the side brush 130 can be determined. The cleaning requirement can be determined, for example, based on the amount of previously collected dirt, an operating time, a predetermined number of revolutions of the side brush 130, a distance traveled by the cleaning robot 100, or on the basis of another parameter.

[0037] In step 610, the side brush 130 can be selectively accelerated and / or decelerated in a jerky motion to guide the brush arm 145 into the described whip-like movement. In particular, multiple accelerations and decelerations can be controlled. This can be done according to a predetermined sequence, which can be variable in amplitude and / or frequency. In one embodiment, the side brush 130 is accelerated or decelerated in a rotational position that ensures that a brush arm 145 is in a predetermined position, so that dirt shaken off by it can preferably be picked up by a cleaning element of the cleaning robot 100.

[0038] In another embodiment, in step 615, the centrifugal element 160 on the cleaning robot 100 can be extended. If a second centrifugal element 405 is present, it can also be extended. Subsequently, the drive unit of the side brush 130 can be controlled to rotate the side brush 130 at a predetermined rotational speed about the axis of rotation 135, so that the brush arms 145 on the centrifugal elements 160, 405 perform the described whip-like movements.

[0039] The corresponding control can take place if the cleaning robot 100 is in the predetermined parking position at the base station 500. In this case, the spinner 160 and / or the additional spinner 405 can be extended from the base station 500.

[0040] After the cleaning of the brush arm 145 is completed in one of steps 610, 615, the procedure 600 can end in step 620. Reference sign

[0041] 100 Cleaning robot 105 Drive wheel 110 Spur wheel 115 Suction nozzle 120 Bristle roller 125 Mop pad 130 Side brush 135 Rotary axis 140 Hub 145 Brush arm 150 Radial inner section 155 Radial outer section 160 (First) centrifugal element 405 (second) centrifugal element 500 base station 600Procedure 605Determine cleaning requirements 610Accelerate / decelerate side brush in a targeted manner 615Extend spin element and rotate side brush in a targeted manner 620End

Claims

1. Method (600) for cleaning a side brush (130) of a cleaning robot (100), wherein the side brush (130) is rotatable about an axis of rotation (135) extending in a vertical direction and has at least one radially projecting brush arm (145); wherein a radially outer section (155) of the brush arm (145) is flexible; wherein the method (600) comprises the following steps: - determining (605) a cleaning requirement of the side brush (130); and - jerkily accelerating or decelerating (610, 615) the brush arm (145) about the axis of rotation (135).

2. Method (600) according to claim 1, wherein the brush arm (145) is accelerated and decelerated (610) multiple times in a predetermined sequence.

3. Method (600) according to claim 2, wherein the sequence (610) is tuned to a resonance frequency of the brush arm (145).

4. Method (600) according to one of the preceding claims; wherein the cleaning robot (100) comprises a suction mouth (115); and the jerky acceleration or deceleration (610, 615) of the brush arm (145) takes place in a predetermined rotational position of the brush arm (145) with respect to the suction mouth (115).

5. Cleaning robot (100) for cleaning a floor surface; wherein the cleaning robot (100) comprises the following elements: - a side brush (130) rotatable about an axis of rotation (135) extending in a vertical direction; - wherein the side brush (130) has at least one radially projecting brush arm (145); - wherein the brush arm (145) is flexible in a radially outer region (155); and - a flailing element (160) that can be lowered into a movement range of the radially outer region (155) of the brush arm (145); - such that the brush arm (145), during its rotational movement about the axis of rotation (135), runs against the lowered flailing element (160) and the radially outer region (155) of the brush arm (145) performs a whipping motion.

6. Cleaning robot (100) according to claim 5, further comprising a drive device which is configured to drive the brush arm (145) at a predetermined speed about the axis of rotation (135), such that the radially outer area (155) of the brush arm (145) is deflected at the centrifugal element (160) against the direction of rotation of the brush arm (145) until its radially outer boundary passes the centrifugal element (160), and the radially outer area (155) then performs the whipping motion.

7. Cleaning robot (100) according to claim 5 or 6, further comprising a suction mouth (115); wherein the whipping movement takes place in the area of ​​the suction mouth (115).

8. Cleaning robot (100) according to one of claims 5 to 7, further comprising a second centrifugal element (405) which can be lowered into the movement range of the radially outer region (155) of the brush arm (145); wherein the centrifugal elements (160, 405) are arranged such that the radially outer region (155) of the brush arm (145) whips against the second centrifugal element (405) after sliding off the first centrifugal element (160).

9. Cleaning robot (100) according to one of claims 5 to 8, wherein the spinning element (160, 405) has a horizontal recess to bring the brush arm (145) into a predetermined vertical position.

10. Base station (500) for a cleaning robot (100) with a side brush (130) rotatable about a rotation axis (135) extending in a vertical direction; wherein the side brush (130) has at least one radially projecting brush arm (145); wherein the brush arm (145) is flexible in a radially outer region (155); wherein the base station comprises a centrifugal element (160, 405) located in a movement range of the radially outer region (155) of the brush arm (145) when the cleaning robot (100) is in a predetermined parking position at the base station (500).

11. Base station (500) according to claim 10, wherein the centrifugal element (160, 405) can be lowered vertically from the range of motion of the radially outer area (155) of the brush arm (145).

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