EP3485783B1 - Floor vacuum cleaner and method for operating a floor vacuum cleaner - Google Patents

Description

The invention relates to the optimization of suction power on a floor vacuum cleaner. In particular, the invention relates to the optimization of an autonomous vacuum cleaning robot.

A vacuum cleaning robot is set up to operate autonomously on a floor surface and to remove dirt from the floor by means of an air flow. Dirt is held back from the air flow by a filter system and the cleaned air flow is released into the environment. If the filter system is loaded with a large amount of dirt, the suction power of the floor vacuum cleaner may decrease. A user is then usually prompted to clean the filter system or to empty a dirt container of the filter system.

It has been shown that the suction power of a floor vacuum cleaner can already decrease significantly before the filter system is saturated with dirt or the dirt container is full. An object on which the present invention is based is to specify an improved technique for maintaining the suction power on a floor vacuum device. The invention solves this problem by means of the subject matter of the independent claims. Subclaims reflect preferred embodiments.

A floor suction device comprises a fan for sucking in an air flow near the floor; a dirt container, in the upper part of which the air flow is directed; a filter disposed at a top of the dirt bin, the filter configured to retain debris from the airflow and allow a cleaned airflow to pass; and a controller. A method of controlling the vacuum cleaner includes the steps of controlling the fan to reduce or stop the flow of air and causing the vacuum cleaner to move.

JP 2006 - 095 106 A relates to a canister vacuum cleaner whose dust filter, when clogged, can be rotated to remove accumulated dust.

DE 10 2012 200 765 A1 proposes a vacuum cleaner with a vacuum cleaner motor and a dust collector. An electric power consumption of the vacuum cleaner motor can be controlled based on a pressure difference of suction air pressures upstream and downstream of the dust collector.

EP 1 547 512 A2 refers to a robot vacuum cleaner whose suction power can be controlled depending on a distance from a bottom of the robot vacuum cleaner to a floor.

DE 10 2010 000 573 A1 shows an electrically driven suction/sweeping device. Depending on a specific condition of a surface to be vacuumed, the power of a brush drive can be increased and the blower power can be reduced at the same time.

According to the invention, it was recognized that the filter tends to become clogged with dirt even before the dirt container is filled. The dirt first accumulates on the filter and is held there by the passing air flow. Areas of the filter that are not covered by dirt are therefore flown through more intensively. Accordingly Dirt accumulates in these places as well, until the filter can be covered with a layer of dirt on one side, which is held on the filter by the passing air flow and reduces the overall air flow. If the air flow is reduced even further, for example by switching the fan to a low power or deactivating it, the movement of the vacuum cleaner can cause the dirt to be shaken off the filter and fall into the dirt container. This allows the filter to be cleaned with on-board tools, so that the suction power is improved again. As a result, in particular an autonomous floor cleaning device, for example in the form of a vacuum cleaning robot, can clean the floor better and require less user intervention to clean the filter or empty the dirt container. The method carried out by the control device can, for example, be initiated periodically or in an event-controlled manner. In particular if the method is carried out regularly, the energy consumption of the blower can be reduced by the overall weaker or less frequently clogged filter, so that the floor vacuum cleaner can work for longer or on a larger floor area.

An event that can be used to perform the method is determining reduced suction power. The suction power can be determined by comparing the air pressure before and after the filter. If a pressure difference across the filter exceeds a predetermined threshold value, it can be assumed that the suction power has decreased. This procedure is already carried out on conventional floor vacuum devices. The method can advantageously make use of a corresponding measuring or processing device.

It is also preferred that the movement is controlled as jerkily as possible. In this case, in different embodiments, the movement can take place in horizontal, in vertical or in both directions. For example, acceleration or deceleration can be controlled in the horizontal direction. A series of short acceleration and/or deceleration pulses can also be controlled.

For a movement in the vertical direction, driving the floor vacuum device over an uneven floor can be controlled. The vacuum cleaner can be used in a household in which uneven floors such as a threshold, a carpet edge or a joint can be driven over by the vacuum cleaner. The floor suction device is usually set up to map the soil it is working on itself. A detected unevenness in the floor can be recorded and actively searched for while the method is running. Alternatively, a longer movement of the vacuum cleaner in the horizontal direction can also be controlled in order to exploit uneven floors that are not detected or mapped. The unevenness of the ground can preferably be driven over at high speed. A known unevenness in the ground or one detected when driving over it can therefore be driven over again, for example, at increased speed.

The unevenness of the ground can also be driven over in different directions. In particular, the uneven ground can be driven over alternately forwards and backwards. Other directions of travel, for example at an angle or perpendicular to the initial direction of travel, are also possible. This can cause non-uniform vibrations of the floor vacuum cleaner, which can cause dirt to be knocked off the filter particularly efficiently.

The floor vacuum device includes a drive motor which is coupled to a drive wheel. The drive motor can be controlled to accelerate the vacuum cleaner in such a way that a section of the vacuum cleaner lying in the direction of travel of the drive wheel is lifted off the floor. This driving technique is also known as a wheelie. Depending on the position of a center of gravity and a chassis geometry of the floor vacuum cleaner and the performance of the drive motor, the section of a conventional floor vacuum cleaner can be lifted a few millimeters up to more than one centimeter from the floor. Both when lifting it and later when it falls back to the ground, vibrations can affect the filter, knocking the dirt off it.

According to the invention, the floor suction device is braked when the section has reached a maximum vertical distance from the floor. This can be determined, for example, by means of an inclination sensor, or a suitable acceleration duration is determined on the basis of driving tests and is permanently specified. This form of acceleration can also be repeated several times. In one embodiment, a suspension of a chassis of the floor vacuum cleaner can be used to the hitting the floor Lift the section off the ground again with another burst of acceleration.

In a further embodiment, the floor suction device can be driven in a horizontal direction at a predetermined speed against an obstacle. A predetermined obstacle can be selected for this purpose, for example a charging station, which can be designed not to be damaged during this maneuver. The greater the impact speed and the harder the impact, the stronger the vibrations affecting the filter can be. It is advisable to limit the speed to a predetermined level to avoid damage to the vacuum cleaner.

The method described herein can be controlled in particular by means of the control device of the floor vacuum cleaner. For this purpose, the control device can include, in particular, a processing device which is embodied, for example, as a programmable microcomputer or microcontroller. The method described can be present in whole or in part in the form of a computer program product with program code means and can in particular run on the processing device. Features or advantages of the method can be transferred to the vacuum cleaner and vice versa.

The floor vacuum device can comprise a first pressure sensor for determining a pneumatic pressure upstream of the filter and a second pressure sensor for determining a pneumatic pressure downstream of the filter. In this case, the control device is set up to determine a reduced suction power if a difference in the pneumatic pressures at the pressure sensors exceeds a predetermined threshold value. If so, the cleaning of the filter described herein can be performed.

Figur 1

eine schematische Darstellung eines beispielhaften Bodensauggeräts;

Figur 2

eine seitliche Ansicht des Bodensauggeräts von Figur 1;

Figur 3

einen Längsschnitt durch ein Bodensauggerät in einer weiteren beispielhaften Ausführungsform;

Figur 4

eine Explosionsdarstellung eines exemplarischen Filtersystems für das Bodensauggerät von Figur 3;

Figur 5

eine weitere Ansicht des Filtersystems von Figur 4; und

Figur 6

ein Ablaufdiagramm eines Verfahrens zum Steuern eines Bodensauggeräts

darstellt.The invention will now be described in more detail with reference to the accompanying figures, in which:

figure 1

a schematic representation of an exemplary floor vacuum cleaner;

figure 2

a side view of the floor vacuum from figure 1 ;

figure 3

a longitudinal section through a vacuum cleaner in a further exemplary embodiment;

figure 4

an exploded view of an exemplary filter system for the vacuum cleaner from figure 3 ;

figure 5

Another view of the filter system from figure 4 ; and

figure 6

a flowchart of a method for controlling a vacuum cleaner

represents.

1 shows a schematic representation of an exemplary floor-vacuum device 100. The floor-vacuum device 100 is set up to travel over a floor 105, preferably automatically, and to clean it in the process. The floor vacuum cleaner 100 can be used for cleaning in particular in a household, for example on a predetermined living space. The floor 105 can be divided into different sections, with an uneven floor 110 being able to be present on or between the sections.

The floor vacuum device 100 comprises a blower 115 for sucking in an air flow near the floor 105, and a dirt container 120 into which the air flow is directed. The dirt container 120 is preferably closed off at its top by means of a filter 130 through which the air flow has to pass in order to leave the dirt container 120 again. The filter 125 can in particular comprise a fleece, a sieve or another mechanical pore filter. The air flow can be released from the filter 125 in an area surrounding the floor vacuum cleaner 100 .

The floor vacuum cleaner 100 also includes a control device 130, which is preferably set up both to control the cleaning function and to control the movement of the floor vacuum cleaner 100. The floor vacuum cleaner 100 can include one or more drive motors 135, which preferably each act on a drive wheel 140. In the illustrated embodiment, two drive wheels 140 are provided which can be driven independently of one another with respective hub drive motors 135. Other embodiments are also possible.

In a preferred embodiment, a first pressure sensor 145 is provided upstream of the filter 125 and a second pressure sensor 150 is provided downstream of the filter 125 . The control device 130 is set up to determine on the basis of a pressure difference determined by means of the pressure sensors 145, 150 whether a suction power of the floor vacuum cleaner is reduced. This can be the case in particular when the pressure difference exceeds a predetermined threshold value over a predetermined time. The floor vacuum cleaner usually includes other components, for example for navigation, for collision avoidance or for power supply, which are 1 are not shown.

It is proposed that the control device 130 be set up to automatically clean a filter 125 clogged with dirt by reducing the power of the blower 115 or switching it off and setting the floor suction device 100 in motion in such a way that it is exposed to vibrations. which encourage dirt to be knocked off the filter 125. This process can be triggered in particular if a reduced suction power has been determined beforehand. In other embodiments, the cleaning can also be controlled, for example, periodically or based on another event.

2 shows a side view of the floor vacuum cleaner 100 of FIG 1 . Various options are available for moving the floor vacuum cleaner 100 in such a way that the filter 125 is cleaned as efficiently as possible. In one embodiment, the vacuum cleaner 100 can be accelerated or decelerated in the horizontal direction. In a further embodiment, it can be driven at a predetermined speed against an obstacle, in particular a stationary one. In yet another embodiment, the unevenness of the floor can be driven over. The speed, direction and frequency of the movements can be varied in each case.

According to the invention, the drive motors 135 can be controlled to accelerate the floor vacuum cleaner 100 so much that a section is lifted off the floor 105 . In the illustrated embodiment, the floor suction device 100 comprises an inlet 205 through which the air flow and possibly dirt from the area of the floor 105 are to be sucked in. The inlet 205 can be slid along the floor 105 or guided a predetermined distance across the floor 105 by means of a wheel, slide or other device. A focus 210 is as close as possible to the drive wheel 140 in the horizontal direction. The focus 210 is between the drive wheel 140 and the inlet 205 or the described, corresponding support element. If the drive motor 135 accelerates the drive wheel 140, a torque acts on the center of gravity 210 about the axis of rotation of the drive wheel 140. With sufficient power from the drive motor 135 and a suitable geometry, a section of the floor vacuum cleaner 100 lying in the direction of travel can be lifted off the floor in the vertical direction 105 is lifted. This section then usually falls back onto the floor 105 again. Falling back can be promoted or reinforced by braking the drive wheel 140 accordingly.

3 shows a longitudinal section through a floor vacuum cleaner 100 in a further exemplary embodiment. Unlike the exemplary embodiment of figures 1 and 2 Here the blower 115 is located downstream of the filter 125. The air flow is sucked in here in the area of the inlet 205 and guided into an upper area of the dirt container 120. The introduction preferably takes place in such a way that the air flow can perform a circular or spiral movement in the dirt container 120 . This can result in areas with a reduced flow velocity, into which dirt can fall from the air flow and collect in the lower area of the dirt container 120 . The air flow leaves the dirt container 120 through the filter 125 arranged in the upper area.

4 shows an exploded view of an exemplary filter system 400, in particular for the vacuum cleaner 100 in the embodiment of FIG 3 . The contaminated air flow enters the dirt container 120 on a side facing the viewer, then passes through it, as indicated, preferably on a circular or spiral path, then runs vertically through the filter 125 and leaves the filter system 400 in an area facing away from the viewer. The filter 125 is preferably designed as a fan or pleated filter to maximize its surface area. Other embodiments are also possible.

figure 5 FIG. 4 shows another view of the filter system 400 of FIG 4 . A view of the upper section of the dirt container 120 is shown from the side on which the dirt is intended to collect. Regarding the presentation of 4 the illustrated part of the dirt container 120 is turned upside down. The incoming air flow is shown in the illustration from figure 5 ie initially directed upwards and can later leave the dirt container 120 vertically downwards through the filter 125 again.

6 10 shows a flowchart of a method 600 for controlling a floor-vacuum device 100. The method presented within the scope of this document can interrupt normal operation of the floor-vacuum device 100. Normal operation can, but does not have to, be counted towards method 600.

In an optional step 605, the floor vacuum device 100 is in normal operation. In a step 605 it can be determined that the suction power of the floor vacuum cleaner 100 has decreased to a predetermined extent. In particular, this measure can be defined by a threshold value that a pressure difference between an upstream and a downstream side of the filter 125 exceeds. If no decrease in suction power was determined, operation can be continued. In other embodiments, whether to clean the filter 125 may also be determined in a different manner.

For cleaning, in a step 615 the power of the fan 115 can be reduced or, in particular, switched off. Simultaneously or subsequently, in a step 620, a movement of the floor vacuum cleaner 100 can be controlled, which is preferably suitable for knocking off dirt adhering to the underside of the filter 125. Falling dirt can accumulate in the lower area of the dirt container 120 in particular. After the dirt has been removed, the usual operation of the floor vacuum cleaner 100 can be continued in an optional step 625 .

In another embodiment, after cleaning the filter 125, it can be determined whether the cleaning was successful. This can be the case in particular when the pressure difference described has fallen below the predetermined threshold value. If the cleaning was unsuccessful, it can be determined that the dirt container 120 is no longer able to hold it. In this case, for example, a user can be asked to empty the dirt container 120 .

Reference sign

100

floor suction device

105

floor

110

uneven ground

115

fan

120

dirt container

125

filter

130

control device

135

drive motor

140

drive wheel

145

first pressure sensor

150

second pressure sensor

205

inlet

210

main emphasis

400

filter system

600

procedure

605

operation

610

Determine decrease in suction power

615

Turn off fan

620

control movement

625

operation

Claims (8)

1. Method (600) for controlling a floor cleaning appliance (100), wherein the floor cleaning appliance (100) comprises the following:

   - a drive motor (135), which is coupled to a drive wheel (140);

   - a fan (115) for drawing in an air current at floor level;

   - a dirt container (120), into the region of which, in particular the upper region, the air current is conducted;

   - a filter (125), which is arranged on the dirt container (120), in particular on an upper side of the dirt container (120),

   - wherein the filter (125) is configured to retain dirt from the air current and to allow a cleaned air current to pass,

   wherein the method (600) comprises the following steps:

   - actuating (610) the fan (115), in order to reduce the air current; and

   - causing (620) a movement of the floor cleaning appliance (100),

   characterised in that

   - the drive motor (135) is actuated to accelerate the floor cleaning appliance (100) such that a section (205) of the floor cleaning appliance (100) lying in the direction of travel of the drive wheel (140) is raised from the floor (105), and

   - the floor cleaning appliance (100) is braked when the section (205) has reached a maximum vertical distance from the floor (105).
2. Method (600) according to claim 1, further comprising a determining (610) of a reduced suction power.
3. Method (600) according to claim 1 or 2, wherein the movement is jerky.
4. Method (600) according to one of the preceding claims, wherein a movement of the floor cleaning appliance (100) is controlled (620) via a floor unevenness (110).
5. Method (600) according to claim 4, wherein the floor unevenness (110) is moved over (620) in alternating directions.
6. Method (600) according to one of the preceding claims, wherein the floor cleaning appliance (100) is moved against an obstacle in the horizontal direction with a predetermined speed.
7. Floor cleaning appliance (100), in particular autonomous vacuum cleaner robot, comprising:

   - a drive motor (135), which is coupled to a drive wheel (140);

   - a fan (115) for drawing in an air current at floor level;

   - a dirt container (120), into the region of which, in particular the upper region, the air current is conducted;

   - a filter (125), which is arranged on the dirt container, in particular on an upper side of the dirt container (120),

   - wherein the filter (125) is configured to retain dirt from the air current and to allow a cleaned air current to pass; and

   - a control apparatus (130), which is configured to actuate the fan (115), in order to reduce the air current and cause a movement of the floor cleaning appliance (100),

   characterised in that

   - the drive motor (135) is actuated to accelerate the floor cleaning appliance (100) such that a section (205) of the floor cleaning appliance (100) lying in the direction of travel of the drive wheel (140) is raised from the floor (105), and

   - the floor cleaning appliance (100) is braked when the section (205) has reached a maximum vertical distance from the floor (105).
8. Floor cleaning appliance (100) according to claim 7, further comprising a first pressure sensor (145) for determining a pneumatic pressure upstream of the filter (125) and a second pressure sensor (150) for determining a pneumatic pressure downstream of the filter (125), wherein the control apparatus (130) is configured to determine a reduced suction power, when a difference between the pneumatic pressures of the pressure sensors (145, 150) exceeds a predetermined threshold value.

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