EP2893861B1 - Method for cleaning contaminated surfaces with a self-propelled cleaning device and cleaning device for same - Google Patents

Description

The invention relates to a self-propelled cleaning device for the automated cleaning of contaminated surfaces having a floor covering structure, wherein the cleaning device comprises working means for cleaning the contaminated surface.

Such self-propelled cleaning devices are used for the automated cleaning of surfaces. They are for example designed as vacuum cleaners, which are then usually referred to as Robotsauger. But there are also self-propelled cleaning devices for wiping smooth floor coverings known.

Such Robotsauger do not always have an optimal cleaning performance on different floor coverings. For different floor coverings require different technical settings of Robotsaugers, such as different fan speed, brush speed and / or speed to achieve optimum cleaning results. In order to achieve optimum cleaning performance on different floor coverings, the technical settings of the robot vacuum cleaner must be adapted to the particular floor covering to be cleaned.

Although it is known to detect the contaminated surface with a camera and / or to measure the motor current of the drive motor of Robotsaugers during the cleaning drive. With a camera, however, heights and depths of the soil of the contaminated area can not be detected. A current measurement allows only a rough distinction, e.g. between a hard floor and a carpet floor.

So far Robotsauger also use fixed technical settings for a cleaning trip. Only when approaching an obstacle, the driving speed is reduced. Therefore, they may consume more energy for certain floor coverings than would be required for optimal technical settings.

The energy storage of Robotsauger is therefore burdened more than necessary so far. In addition, incorrect technical settings can also lead to damage to floor coverings, such as damage to a carpet runner at too high brush speed. Or the suction power of Robotsaugers is too low, for example, at high speed with low fan speed on a hard floor, so that the contaminated area is insufficiently cleaned.

From the US 2007/0271004 A1 is a cleaning robot known at the wheels of a carpet detection device is arranged. From the US 2005/0166354 A1 is a Vacuum robot known which detects the nature of a ground surface to be cleaned via optical sensor elements.

The object of the invention is therefore to provide a self-propelled cleaning device, with which the disadvantages of the above-mentioned prior art are avoidable, and therefore, regardless of the floor covering of the contaminated surface optimum suction without damaging the flooring with low energy consumption allows.

According to the invention, this object is achieved by a self-propelled cleaning device having the features of claim 1. Advantageous embodiments can be found in the dependent claims.

The self-propelled cleaning device is provided for automated cleaning of a contaminated surface having a flooring structure. It has working means for cleaning the contaminated surface.

The cleaning device is characterized in that it comprises a sensor for detecting the floor covering structure of the contaminated surface.

The contaminated surface is preferably the surface of a carpet, a carpet, a tile floor, a stone floor, a laminate floor, a parquet floor and / or a PVC floor. However, the cleaning device is preferably also suitable for other floor coverings not mentioned in this list.

In order to detect the flooring structure of the contaminated area, or the floor coverings, the sensor is preferably designed as a scanning sensor. Such a scanning sensor is preferably designed to scan the contaminated surface to detect imperfections and / or undulations of the contaminated surface.

According to the invention, the sensor comprises a piezoelectric sensor which cooperates with a scanning probe and forms the scanning sensor. Such a scanning sensor may also be referred to as a finger sensor. In an alternative preferred embodiment, it is provided that the piezo sensor cooperates with a spring-mounted wheel and forms the scanning sensor. In both embodiments, the piezoelectric sensor is preferably arranged so that it detects a change in height of the wheel or the scanning probe.

It is further preferred that the self-propelled cleaning device comprises a device control, which is adapted to control the working means in response to the sensor signal of the sensor.

The working means of the cleaning device preferably comprise a main brush, a side brush, a peripheral brush, a drive motor, a wheel and gear unit, a blower and / or further control sensors. But there are also more or other work equipment preferred, especially if the cleaning device is alternatively or additionally suitable for wiping smooth floors.

By the device control of the cleaning device controls its working means in response to the sensor signal, the operation of the cleaning device is systematically changed in dependence on the detected with the sensor flooring structure.

Particularly preferably, the device control controls technical settings of the work equipment. In this case, the term work equipment such technical devices of the self-propelled cleaning device to understand that are relevant for the cleaning of the contaminated area. Preferably, the term work equipment therefore includes a main brush, a side brush, a peripheral brush, a drive motor, a wheel and gear unit, a fan and / or other control sensors of the cleaning device.

In a preferred embodiment, the device control controls the technical settings speed and / or direction of rotation of the main brush, the side brush, the edge brush, the drive motor and / or the wheel and gear unit - and thus the driving speed of the cleaning device -, and / or the suction power at the blower, and / or the sensitivity of the further control sensors in dependence on the detected sensor signal of the sensor. If the self-propelled cleaning appliance is suitable for wiping smooth floors, it accordingly controls the technical settings of the other or further working means.

Since the device control controls the technical settings of his work equipment as a function of the detected floor covering structure, the self-propelled cleaning device achieves an approximately optimal cleaning result for each floor covering structure with as little energy consumption as possible for the respective floor covering. Compared to a conventional, during a cleaning trip with the same technical settings of the Working means working, self-propelled cleaning device allows the cleaning device according to the invention therefore a significantly improved utilization of its energy storage or batteries.

In order to detect the floor covering structure, it is preferred that the device control is additionally designed to detect the floor covering structure by means of a comparison process of the measured sensor signal with reference signals. For the comparison process, it is preferable for the reference signals to show the floor covering structures for a specific driving speed of the self-propelled cleaning device. The comparison process of the measured sensor signal with the reference signals first preferably comprises a conversion of the measured sensor signal into a converted sensor signal which is calculated as if the self-propelled cleaning device had been operated at the constant defined travel speed. As a result, differences in the driving speed are taken into account. Subsequently, the comparison process comprises the comparison of the converted sensor signal with the reference signals.

Further preferably, the self-propelled cleaning device has a read-only memory for storing conversion algorithms for converting the measured sensor signal into the converted sensor signal, as well as the reference signals.

• ein Sensorsignal mit einem Sensor gemessen wird;
• eine Bodenbelagsstruktur einer verunreinigten Fläche durch einen Vergleichsprozess des Sensorsignals mit Referenzsignalen erfasst wird; und
• technische Einstellungen mindestens eines Arbeitsmittels des selbstfahrenden Reinigungsgerätes in Abhängigkeit von der erfassten Bodenbelagsstruktur verändert werden.

Preference is given to a method for cleaning contaminated surfaces with a self-propelled cleaning device according to the invention, in particular with a robotic vacuum cleaner, in which

• a sensor signal is measured with a sensor;
• a flooring structure of a contaminated area is detected by a comparison process of the sensor signal with reference signals; and
• technical settings of at least one working means of the self-propelled cleaning device depending on the detected flooring structure to be changed.

The sensed sensor signal allows the detection of a variety of different floor coverings and their structure by comparison with the reference signals, such as sensitive, normal or insensitive carpets, hard floors, stone or tile floors, laminate or PVC floors, parquet floors. Sensitive carpets are for example high-pile carpets, insensitive carpets are, for example, close-meshed carpets such. B. Wilton carpets. For example, delicate stone or tile floors are marble floors or high-gloss floors.

In this case, the comparison process comprises a conversion of the measured sensor signal into a converted sensor signal, which reproduces the measured sensor signal for a defined constant driving speed, and a comparison of the converted sensor signal with the reference signals.

Depending on the floor coverings structure, the technical settings of the robotic vacuum equipment are adjusted.

The technical settings changed in dependence on the detected floor covering structure are preferably a rotational speed and / or a direction of rotation of the main brush, a side brush, a peripheral brush, a drive motor and / or a wheel and gear unit of the self-propelled cleaning device, a suction power of a blower of the self-propelled cleaning device, and / or a sensitivity of further control sensors of the self-propelled cleaning device.

The sensor signal also makes it possible to detect a direction of extension of carpet edges and / or joints between joined tiles. It is preferred that the direction of travel of the self-propelled cleaning device is adjusted as a function of the extension direction, so that the direction of travel of the cleaning device is arranged at an angle to the joint direction. As a result, the brushes engage better in the joints and along the edges, and the cleaning result is improved.

In a preferred embodiment, the speed of the main brush is lowered for delicate carpets, particularly high pile carpets, so as not to rupture or tear the carpet threads.

In a further preferred embodiment, the speed of the side brushes is lowered in hard floors, not to slam away lying on them dirt.

In a further preferred embodiment, the rotational speed of the wheel and gear unit is lowered in high-pile carpets and tiles, so that the driving speed of the robotic vacuum cleaner is lowered.

In a further preferred embodiment, the sensitivity of other control sensors is increased in sensitive floor coverings and / or lowered in insensitive floor coverings.

In a preferred embodiment, the measured sensor signal or the converted sensor signal is filtered prior to the comparison to noise, for example by Contamination of the contaminated area or vibration of the cleaning device due to its operation, filter out.

By detecting the flooring structure, it is possible to adapt the technical settings of technical facilities of the robotic vacuum cleaner, in particular its working equipment. This not only improves the cleaning result but also optimizes energy consumption and therefore battery performance. Overall, the cleaner therefore works cleaner and cheaper than conventional cleaning equipment. In addition, the flooring structure can be included in the navigation strategy.

Fig. 1

zeigt in (a) und (b) jeweils einen Ausschnitt aus einem selbstfahrenden Reinigungsgerät mit einem Sensor zum Erfassen der Bodenbelagsstruktur, wobei der Sensor ein piezoelektrischer Sensor ist, in (c) das Reinigungsgerät aus (b) am Boden, und in (d) das Reinigungsgerät aus (b) abgehoben vom Boden;

Fig. 2

zeigt schematisch einen Raum, auf dessen Boden der Verlauf einer Reinigungsfahrt eines selbstfahrenden Reinigungsgerätes dargestellt ist;

Fig. 3

zeigt in (a) - (c) schematisch einen weiteren Raum, auf dessen Boden die Verläufe von Reinigungsfahrten des selbstfahrenden Reinigungsgerätes dargestellt sind, in (d) ein Sensorsignal eines Verlaufes einer in (a) - (c) dargestellten Reinigungsfahrt, und in (e) - (h) Referenzsignale verschiedener Bodenbelagsstrukturen; und

Fig. 4

zeigt einen weiteren Verlauf einer Reinigungsfahrt durch den Raum aus Fig. 3.

Embodiments of the invention are shown purely schematically in the following drawings and will be described in more detail below. It shows:

Fig. 1

shows in (a) and (b) respectively a section of a self-propelled cleaning device with a sensor for detecting the flooring structure, wherein the sensor is a piezoelectric sensor, in (c) the cleaning device of (b) on the ground, and in (d) the cleaning device from (b) lifted off the ground;

Fig. 2

schematically shows a room on the bottom of the course of a cleaning trip of a self-propelled cleaning device is shown;

Fig. 3

shows in (a) - (c) schematically another room, on the bottom of the courses of cleaning trips of the self-propelled cleaning device are shown, in (d) a sensor signal of a course of a (a) - (c) cleaning trip shown, and in ( e) - (h) reference signals of various flooring structures; and

Fig. 4

shows a further course of a cleaning trip through the room Fig. 3 ,

The self-propelled cleaning device of Fig. 1 is a Robotsauger 1, which is intended for cleaning, especially for vacuuming, carpets and smooth floors. The invention is not limited to such Robotsauger 1, but also applicable to self-propelled cleaning equipment, which are additionally or alternatively provided for wiping smooth floors. In the following, the terms self-propelled cleaning device and Robotsauger 1 are used synonymously.

The robotic vacuum cleaner 1 has a drive system which comprises a drive motor, a gear unit and one or more, optionally independently drivable, Drive wheels includes. From the drive system shows the FIG. 1 Here, however, only schematically a wheel and gear unit 16 of the drive system.

In addition, the drive system of the Robotsaugers 1 on a support wheel 14 which is formed either pivotable or as a rotatable ball in all directions. In mutually independent control of the directions of rotation and rotational speeds of the drive wheels of Robotsauger 1 perform any movements on a surface 20 to be cleaned.

As to be cleaned area 20 is in Fig. 1 (a) a smooth floor, and in the Fig. 1 (b) - (d) a carpet presented.

The robotic vacuum cleaner 1 has in a suction region 10 a rotating main brush 17 and rotating side brushes 18, which are provided to support suction nozzles, not shown. With the suction nozzles impurities, such as dust and dirt particles, in a known manner with a filter system, e.g. a vacuum cleaner bag, which is arranged in a dust cassette 19, collected. The suction nozzles interact with a fan motor 15.

The suction area 10, the rotating brush 17, 18, the drive system and the filter system with the fan motor 15 represent the decisive for the cleaning of the contaminated surface 20 working means of Robotsaugers 1. Further existing for the operation of Robotsaugers 1 technical facilities, such as a rechargeable Battery for power supply, charging connections for the battery or a removal option for the vacuum cleaner bag are in the Fig. 1 not shown for reasons of clarity.

Robotsauger 1 has a device control 11, which is connected to the working means 15-18 for the control thereof. A control sensor and / or a camera device with which the robot vacuum cleaner 1 continuously detects its surroundings in order to control, for example, the direction of travel and / or the travel speed in a known manner, are likewise not shown here for reasons of clarity.

Robotsauger 1 of this embodiment has a sensor 12 which is designed as a pressure sensor. For this, it comprises a piezoelectric sensor which is provided for detecting the floor covering structure of the floor 2, the surface 20 of which is to be cleaned. In the following, the terms sensor 12 and piezoelectric sensor are used interchangeably. The piezoelectric sensor 12 cooperates via a spring 13 with the support wheel 14 of the Robotsaugers 1, so that a scanning sensor is formed. Upon compression of the support wheel 14, the sensor 12 via the spring 13 together pressed. This change leads to a change in a voltage U built up by the piezoelectric sensor 12 (see FIG. Fig. 3 (d) ), which is referred to as an electrical sensor signal 70 (see FIG. Fig. 3 (d) ) is detected. The sensor signal 70 is therefore a measure of the waviness of the floor covering.

In the embodiment of Fig. 1 (b) For example, instead of the spring 13 and the jockey wheel 14, the piezoelectric sensor 12 cooperates with a sensing probe 12 'which sweeps over the contaminated surface 20 and compresses the piezoelectric sensor 12 when a ripple occurs, such that the voltage across the piezoelectric sensor 12 decreasing voltage U changes and can be detected as a sensor signal 70.

In the Fig. 1 (c) and (d) the sensor 12 is the Fig. 1 (b) via a pivoting mechanism 101, 102 connected to the wheel and gear unit 16. When not attached to the bottom 2 Robotsauger 1, the sensor 12 with the Abtastfinger 12 'is raised so that it is surrounded by a housing 100 of the Robotsaugers 1 and therefore protected. Only when depositing the Robotsaugers 1 to the bottom 2 of the sensor 12 is extended with the Abtastfinger 12 'so that it sweeps over the contaminated surface 20.

In Fig. 2 schematically a space 3 is shown, in which a first round carpet 41 and a second square carpet 42 are arranged. A robotic vacuum cleaner (not shown here) travels over a driving route 5 represented by way of example during a cleaning drive. The flooring structure changes as the carpets 41, 42 pass over, with the result that the measured sensor signal 70 changes. In a first travel range 51, the measured sensor signal 70 corresponds to that of the floor covering 8 without one of the carpets 41, 42, in a second travel area 52 it corresponds to that of the first or second carpet 41, 42, and in a third travel area 53 it corresponds to a transition from Floor covering 8 without one of the carpets 41, 42 to the first or second carpet 41, 42, ie an edge.

If the quality of the carpets 41, 42 differs, the sensor signals 70 detected by the sensor 12 also differ from one another when passing over the first and second carpets 41, 42 and, if appropriate, the sensor signals 70 detected by the sensor 12 when passing over the transition from the floor covering 8 without one of the carpets 41, 42 to the first carpet 41 and from the floor covering 8 without one of the carpets 41, 42 to the second carpet 42 from each other.

The Fig. 3 (a) shows a further room 3 with several furniture 6. By way of example, possible routes are shown 5 Robotsaugers 1 at a first cleaning trip. In the Fig. 3 (b) In addition, the spatial points 50 are shown at which the sensor 12 has detected voltage peaks U _MAX . The sensor signal 70 of the sensor 12 is in the Fig. 3 (d) for a defined Route 28, the in Fig. 3 (c) is shown, exemplified. The illustration shows the course of the voltage U across the piezoelectric sensor 12 as a function of the time t.

Due to the rectilinear voltage curve of the sensor signal 70 between the measured voltage peaks U _MAX can be concluded that a smooth floor. Due to the presence of voltage peaks U _Max can be concluded that joint 81st The uniform distribution of the voltage peaks U _MAX , that is, the uniform time interval A (s. Fig. 3 (d) ) of their occurrence from one another, makes it possible to draw conclusions about a joint direction 91, 92 in which the joints 8 travel over, relative to a direction of travel 9 of the robot vacuum cleaner 1. Namely, the direction of travel 9 at a constant speed, uniform tiles 8 and equally distributed stress peaks U _{MAX is arranged} transversely to a joint direction 91, 92. And based on the duration of the voltage peaks U _MAX and / or their amount, laminate, stone and tiled floors can be distinguished from each other.

The Fig. 3 (e) - (h) show reference signals 71 - 76 for different floor coverings. Shown is the voltage U detected in the sensor 12 in [V] (volts) over the time t in [s] (seconds). The reference signals 71-76 correspond to fictitious sensor signals which would be detected when the floor coverings were driven over at a constant defined travel speed of the robot vacuum cleaner 1.

In Fig. 3 (e) For example, a first reference signal 71 for a laminate floor is shown. The voltage peaks U _MAX indicate the presence of a waviness, in this case a joint 8 between two laminate tiles 8 or strips (see FIG. Fig. 3 (c) ). A constant voltage curve indicates a flat bottom. Since the distance A between the voltage peaks U _MAX is equal here, the laminate floor is in a straight line transverse to the joint direction 91, 92 (s. Fig. 3 (c) ) run over. When driving over the laminate floor at an angle to the joint direction 91, 92, the waveform voltage spikes U _MAX at different distances (not shown), which indicate a distance of the joints 81 from each other and from those at a known speed on the dimensions of the laminate tiles or strips can be closed. From the height of the voltage peaks U _MAX can also be closed to the depth of the joints.

The Fig. 3 (f) shows a second reference signal 72 for a tiled floor. Here too, the voltage peaks U _MAX indicate the presence of the waviness, namely a joint 81 between two tiles. Again, the distance A between the voltage peaks U _{MAX is the} same, which indicates a straight over driving the joints 81 transverse to the joint direction 91, 92. The stress peaks U _MAX take longer in comparison to those in the laminate floor, which at the same driving speed and the same angle of the direction of travel 9 to the joint direction 91, 92 indicates a wider joint 81 and allows the conclusion on stone or tile floor compared to laminate flooring.

The Fig. 3 (g) shows in sequence an earlier third reference signal 73 for a close mesh carpet such as a Wilton floor, and a later fourth reference signal 74 for a high pile carpet. Since carpets have a non-uniform waviness, the waveform of these reference signals 73, 74 here varies unevenly, and in fact the larger the higher the pile of the carpet.

The Fig. 3 (h) FIG. 5 shows an earlier fifth reference signal 75 for a smooth floor, for example for a PVC floor, and a later sixth reference signal 76 for a smooth floor with a structure, for example for a dimpled PVC floor.

The sensor signal 70 of the sensor 12 is detected via a defined route 28 and first converted in a comparison process to the constant defined vehicle speed in a converted sensor signal. Subsequently, the flooring is identifiable by comparison with the reference signals 71-76. By comparing the in the Fig. 3 (d) shown sensor signal 70, for example, for the room 3 of Fig. 3 (a) - (c) be closed on a laminate floor of laminate tiles 8.

Not only are carpets of hard floors clearly distinguishable, but also the flooring structure, such as smooth, knobbed, deep pile or close-meshed, is recognizable. In addition, the joint direction 91, 92, in the boards, strips and / or tiles 8 of a floor 2 are laid, and / or the dimensions of the boards and / or tiles 8, with the aid of pointing to the joints 81 voltage peaks U _MAX detected , This information can also be used for the calculation of an optimized route 5.

LIST OF REFERENCE NUMBERS

1

Robot vacuum cleaners

10

suction area

100

casing

101

Swivel mechanism

102

Swivel mechanism

11

device control

12

(piezoelectric) sensor

12 '

scanning probe

13

feather

14

Wheel, support wheel

15

fan

16

Wheel and gear unit

17

main brush

18

side brush

19

suction tank

2

ground

20

Contaminated area

28

Defined driving distance

3

room

41

First carpet

42

Second carpet

5

cleaning section

50

space point

51, 52, 53

first - third cleaning area

6

Furniture

70

sensor signal

71 - 76

reference signals

8th

Flooring, tile, laminate

81

groove

9

direction of travel

91, 92

joint direction

U

Voltage, measured in volts [V]

U _MAX

Transient

t

Time, measured in seconds [s]

Claims (6)

1. Self-propelled cleaning device (1) for automatically cleaning a contaminated surface (20) having a floor covering structure, the self-propelled cleaning device (1) comprising tools (15-18) for cleaning the contaminated surface (20) and a sensor (12) for detecting the floor covering structure of the contaminated surface (20), the sensor (12) being designed as a scanning sensor, characterised in that the sensor comprises a piezoelectric sensor that interacts with a wheel (14) of the self-propelled cleaning device (1).
2. Cleaning device (1) according to claim 1, characterised in that said device comprises a device control means (11) which is designed to control the tools (15-18) on the basis of a sensor signal (70) from the sensor (12).
3. Cleaning device (1) according to either claim 1 or claim 2, characterised in that the tools (15-18) are a main brush (17), a side brush (18), an edge brush, a drive motor, a wheel and transmission unit (16), a fan (15) and/or additional control sensors.
4. Cleaning device (1) according to either claim 2 or claim 3, characterised in that the device control means (11) controls technical settings of the tools (15-18), in particular the rotational speed and/or direction of rotation of the main brush (17), the side brush (18), the edge brush, the drive motor and/or the wheel and transmission unit (16), the suction power of the fan (15) and/or the sensitivity of the additional control sensors.
5. Cleaning device (1) according to any of claims 1 to 4, characterised in that the device control means (11) is designed to detect the floor covering structure by comparing the measured sensor signal (70) with reference signals (71-76).
6. Cleaning device (1) according to claim 5, characterised in that said device comprises a read-only memory for storing the reference signals (71-76).

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