EP3592191B1 - Window cleaning robot - Google Patents

Description

The present invention relates to a window cleaning robot, comprising a fastening device for adhering to a window surface, a drive device for moving across the window surface and a cleaning device for cleaning the window surface, the cleaning device having at least one cleaning element which is on a contact side of the window cleaning robot, which during its use facing the window surface, is arranged, wherein the window cleaning robot comprises at least one reservoir for cleaning liquid, at least one fluid channel, via which cleaning liquid from the at least one reservoir can be fed to the at least one cleaning element to moisten it, and at least one arranged on or in the at least one fluid channel Resistance element for providing a resistance against a flow of cleaning liquid through the fluid channel from the at least one reservoir to the at least one cleaning element.

A window cleaning robot is for example in the EP 3 181 027 A1 described. The window cleaning robot enables autonomous cleaning of a window surface, ie in particular a vertically oriented surface. The window cleaning robot is designed to be self-propelled and self-steering. The window cleaning robot can adhere to the window surface by means of a fastening device operated by negative pressure, and the drive device enables the window cleaning robot to move on the window surface, with the window cleaning robot moving along a main direction of movement or forward direction and the window surface, for example, along a meandering cleaning path.

The window cleaning robot described in the EP reference document has a cleaning device with a cleaning brush leading in the main direction of movement in order to loosen coarse dirt from the window surface. The cleaning brush in the main direction of movement comprises the following Window cleaning robot, the cleaning device mentioned at the beginning with at least one cleaning element. The cleaning element, for example a cleaning cloth, is arranged on the contact side of the window cleaning robot, which faces the window surface when it is in use. On the contact side, the window cleaning robot defines a contact plane or touch plane that coincides with a plane defined by the window face.

The EP 3 181 027 A1 describes that the window surface can be wetted with a cleaning liquid before cleaning. Alternatively, there is the possibility of wetting the cleaning element with the cleaning liquid. The cleaning element can be used to remove dirt from the window surface.

The DE 10 2006 033 668 A1 describes a cleaning device for a preferably flat surface, in particular a window pane. The cleaning device has a body and a cleaning device as well as a dosing device that supplies the cleaning device with cleaning agent and also a suction cup that holds the cleaning device in contact with the surface to be cleaned and rests sealingly on the surface at the edge, with a suction device sucking air out of the suction cup and out of the body blows out. At least part of the air blown out by the suction device can be supplied to the dosing device as pressure medium for dispensing the cleaning agent.

The object of the present invention is to provide a window cleaning robot of the type mentioned at the outset, in which user-friendly moistening of the cleaning element is made possible with regard to a better cleaning result.

This object is achieved by a window cleaning robot according to the invention with the features of claim 1.

The window cleaning robot according to the invention has at least one storage container. As a result, there is the possibility that the window cleaning robot carries a supply of cleaning liquid with it, so that the user does not have to wet the window surface and/or the cleaning element. This simplifies the handling of the window cleaning robot. In this case, the cleaning liquid can be supplied to the at least one cleaning element via the at least one fluid line from the reservoir. Since the window cleaning robot is usually used on a vertically oriented window surface, the amount of cleaning liquid that is applied to the window surface via the at least one cleaning element is important. On the one hand, it is desirable to apply a sufficient amount to achieve a better cleaning result. On the other hand, it is desirable to avoid an excessive amount of cleaning liquid that remains on the window surface after cleaning and, if passed over again, can impair the ability of the window cleaning robot to adhere to the window surface or the cleaning result. For this purpose, the window cleaning robot according to the invention comprises at least one resistance element arranged on or in at least one fluid channel. The resistance element, which can also be referred to as a throttle element in this case, forms a resistance with which a flow of the cleaning liquid through the fluid channel to the cleaning element can be influenced, in particular inhibited and, if necessary, also completely prevented. The at least one resistance element makes it possible, given a structurally relatively simple design of the cleaning device, to meter the amount of cleaning liquid supplied to the at least one cleaning element in such a way that preferably as much cleaning liquid as possible and as little as necessary is applied through the resistance area formed by the resistance element can.

With regard to a structurally simple design, it is favorable if the at least one resistance element is designed to be passive, for example without moving parts. Although the use of at least one controllable is conceivable Valve, to simplify the construction, however, the cleaning device can preferably do without a valve on at least one fluid channel.

Accordingly, it is advantageous that the at least one resistance element is liquid-permeable.

In the embodiment according to the invention, it is favorable that the at least one resistance element is formed separately from the at least one fluid channel and is arranged on or in it. As a result, the structural design can be simplified, and depending on the requirements of the window cleaning robot, there is the possibility, for example, of providing resistance elements of different types that provide different resistances. The resistance element can be arranged, for example, at an inlet or at an outlet of the fluid channel, or be positioned in it. Advantageously, the resistance element is arranged in a form-fitting manner in the fluid channel.

It is advantageous that the at least one resistance element is or forms an absorber element or filter element. A cleaning function of the filter element for the cleaning liquid is possible, but not absolutely necessary. The absorber element or filter element is in particular liquid-permeable, so that the flow of cleaning liquid through the at least one fluid channel is at least impeded. To this end, the absorber element or filter element may have intrinsic passageways and/or a porous nature.

The absorber element makes it possible to take up and hold a certain amount of cleaning liquid (eg physically and/or chemically), and it can be used to a certain extent to temporarily store the cleaning liquid while forming the resistance area. When the absorber element comes into contact with the cleaning liquid, this spreads out therein, for example under the capillary effect. Cleaning fluid can from the Absorber element exit again, but is prevented by the capillary action. However, cleaning liquid can be released from the absorber element, in particular when pressure is applied to the absorber element, as explained below. This allows targeted moistening of the cleaning element to be achieved.

It is particularly advantageous if the cleaning liquid can be temporarily absorbed by the resistance element, e.g. physically and/or chemically, and can then be released again, with the resistance element serving to a certain extent as an intermediate store for cleaning liquid.

It can be provided that the cleaning device comprises a plurality of fluid channels via which cleaning liquid can be supplied to the at least one cleaning element.

In an advantageous embodiment, the fluid channels are arranged side by side along a direction of extension of the at least one cleaning element. For example, the at least one cleaning element has a longitudinal extent transverse to a main direction of movement of the window cleaning robot (this direction of extent is also referred to below as the transverse direction). The fluid channels can be arranged side by side in the transverse direction, for example.

The fluid channels are advantageously configured identically.

It proves to be advantageous if the cleaning device comprises a plurality of resistance elements which are assigned to a respective fluid channel, the resistance elements preferably being of identical design.

In an advantageous embodiment, precisely one reservoir is provided, from which the at least one cleaning element and in particular the precisely one cleaning element can flow via the plurality of fluid channels Cleaning liquid can be fed. Accordingly, it is favorable if the cleaning device includes exactly one reservoir and exactly one cleaning element. For example, several fluid channels are provided.

Exactly one reservoir is designed to extend longitudinally, for example, in the transverse direction of the window cleaning robot. If there are a plurality of storage containers, it can be provided that these are arranged laterally next to one another in the transverse direction.

The at least one cleaning element preferably extends transversely to a main direction of movement of the window cleaning robot (in the transverse direction) and is designed as a cloth or sponge.

The main direction of movement can also be regarded as the forward direction of the window cleaning robot, along which main direction of movement or forward direction the window cleaning robot usually travels over the window surface. The main direction of movement can be oriented in any direction relative to a direction of gravity (or vertical), depending on the travel path of the window cleaning robot, in particular upwards counter to the direction of gravity, downwards in the direction of gravity, perpendicular to the direction of gravity or oblique to the direction of gravity.

In an embodiment that is not claimed, it can be provided that the at least one resistance element is formed by a narrowing of the cross section of the at least one fluid channel. The fluid channel, including its inlet and/or its outlet, can have a narrowing of the cross section, which makes it difficult for cleaning liquid to pass through the fluid channel, in order to form a resistance area.

It has proven to be advantageous if the at least one resistance element provides essentially the entire resistance to a flow of cleaning liquid through the at least one fluid channel.

It can be provided that the absorber element or filter element is designed to be elongated and is preferably aligned in a direction of progression or extension of the at least one fluid channel, in particular when arranged in the fluid channel.

The absorber element or filter element consists, for example, of a porous material or includes a porous material. The porous texture of the absorber element or filter element allows the cleaning liquid to flow through, but opposes the flow through the fluid channel with resistance.

It can be provided that the absorber element or filter element includes passages for the cleaning liquid. The passages can have a relatively small cross section, so that the passage of cleaning liquid is impeded.

In an advantageous embodiment, the absorber element or filter element consists at least partially of at least one of the following: cellulose-based material, cotton or cotton-based material, fiber material (natural and/or synthetic fibers) and/or polymer material.

In an advantageous embodiment, it proves to be favorable if the absorber element or filter element is a tooth floss roll. Such a dental floss roll, for example made of cotton-based material, is used in dentistry to absorb saliva and coolant during drilling. In practice, such an absorber element or filter element proves to be advantageous for use in window cleaning robots.

In another advantageous embodiment, the absorber element or filter element is a cigarette filter, for example, which consists of cellulose-based material, for example.

It is favorable if the window cleaning robot has a pump unit for conveying a gas, for example air, and for providing a pressure difference across the at least one resistance element such that when the pressure difference is present, cleaning liquid flows through the at least one fluid channel, with the at least one resistance element favorably having sufficient resistance provides that the cleaning liquid, in the absence of the pressure difference, on flowing through the at least a fluid channel is prevented. A pressure difference can be provided with the pump assembly, as a result of which different pressures occur in particular on different sides (upstream and downstream) of the at least one resistance element and the pressure on the upstream side is higher than on the downstream side. When the pressure difference is present, the cleaning liquid can flow through the at least one fluid channel, so that under the action of the pump unit, the inhibiting effect of the resistance element is overcome in such a way that a minimum amount or advantageously a desired amount of cleaning liquid is supplied to the at least one cleaning element.

In contrast, the at least one fluid channel is preferably not flowed through by the at least one cleaning liquid in the absence of the pressure difference, under the effect of the resistance element.

In the above-mentioned embodiments, cleaning liquid can be "collected" on the at least one resistance element, for example in the absence of the pressure difference, for example by being absorbed in the absorber element. If the pressure difference occurs across the resistance element, the cleaning liquid is pumped through the at least one fluid channel and the at least one cleaning element supplied, for example by cleaning liquid dissolves from the absorber element.

It is favorable if the at least one resistance element provides sufficient resistance that the cleaning liquid, in the absence of the pressure difference, is prevented from flowing through the at least one fluid channel regardless of the orientation of the window cleaning robot relative to a direction of gravity. This makes it possible to prevent the at least one storage container from leaking out unintentionally, for example when the window cleaning robot is positioned on the contact side on a horizontal installation surface, for example that of a table. In contrast, during operation of the window cleaning robot, when the pump unit is used, the at least one cleaning element can can also be moistened when the window cleaning robot is positioned horizontally.

The window cleaning robot advantageously includes a control device for controlling the pump unit.

The pump unit can preferably be controlled in order to provide a discrete pressure difference across the at least one resistance element. For example, pressure differences can be provided by the pump unit at intervals of approximately one second, with a respective pressure surge being able to last approximately 10 ms to 50 ms, for example. Provision can be made for an operator to be able to set the intervals and/or the duration of the pressure surges in order to ensure optimal moistening of the at least one cleaning element.

In a different embodiment, it can be provided that the pump unit can be acted upon continuously in order to provide the pressure difference.

It is favorable if the pump assembly is in fluid connection with the at least one storage container via at least one fluid line and if an overpressure can be generated in the at least one storage container by means of the pump assembly. The pump assembly is in fluid communication with the at least one reservoir, for example via at least one hose line. The interior of the reservoir can be subjected to excess pressure, as a result of which a pressure difference arises across the at least one resistance element. As a result of the overpressure, cleaning liquid can be pumped through the fluid line, cleaning liquid for example being released from the absorber element, as has been described above.

It was already mentioned at the outset that the window cleaning robot includes a fastening device. It is favorable if the fastening device comprises an absorbent body and if the pump unit is part of the Fastening device of the window cleaning robot is, for example, for applying negative pressure to the suction body. For example, the pump unit can evacuate a space between the suction body and the window surface or cause the suction body to deform so that the window cleaning robot can adhere to the window surface.

It has proven to be favorable if the control device is in an operative connection with in particular at least one valve in order to selectively bring the pump unit into fluid connection with the suction body. Accordingly, it can be provided that the suction body is used to secure the window cleaning robot on the window surface, apart from the normal cleaning operation, during which the window cleaning robot moves over the window surface. The control device can actuate the at least one valve in order to "suck firmly" onto the window surface. During the cleaning operation, the at least one valve to the suction body is closed, for example, as a result of which the pump unit can provide the pressure difference across the at least one resistance element, as mentioned above. However, it can also be provided that a valve is not required and can be omitted.

A diaphragm pump, for example, is suitable as a suitable pump unit for the above-mentioned purpose, the suction side of which can be connected to the suction body and the pressure side of which can be connected, for example, to the at least one reservoir. If only discrete pressure surges are delivered to provide the pressure difference, this can be sufficient to moisten the cleaning element, with the suction body not yet being activated.

The use of the pump unit of the fastening device allows a structural simplification of the window cleaning robot. A separate pump unit for pressurizing the cleaning device is not required.

In an advantageous embodiment, it can be provided that, contrary to the above explanations, no pump unit for providing a pressure difference is present or used.

In an advantageous embodiment, it has proven to be favorable if the at least one fluid channel has at least one feed section, via which cleaning liquid enters the at least one fluid channel, and a discharge section arranged at an angle to the at least one feed section, via which the cleaning liquid is discharged in the direction of the at least one cleaning element can be guided, wherein the at least one feed section and the discharge section are aligned at an angle to one another.

The angle between the at least one feed section and the discharge section can be approximately 90°, for example.

The at least one feed section is favorably aligned parallel or substantially parallel to the contact plane of the window cleaning robot defined on the contact side. The above-mentioned contact plane defined by the window cleaning robot can coincide with the plane defined by the window surface. The at least one feed section preferably runs parallel to the contact plane.

The dispensing section is preferably oriented transversely or substantially transversely to the plane of contact.

It has proven to be advantageous if the at least one resistance element, in particular the absorber element or filter element, is arranged in the discharge section. For example, cleaning liquid can be supplied via the at least one feed section and pumped through the at least one resistance element in the direction of the at least one cleaning element under the action of the pump unit.

As already mentioned, the at least one resistance element can advantageously be wetted in particular and is suitable for absorbing and holding a certain amount of cleaning liquid. In particular, under the action of the pump unit and the resulting pressure difference, a drop of cleaning liquid can form, which detaches itself from the resistance element and moistens the at least one cleaning element.

It is advantageous if the at least one feed section is arranged in the at least one storage container or engages in it in such a way that the at least one feed section is arranged at a distance from a bottom wall of the at least one storage container when the window cleaning robot is oriented with the contact side vertically downwards. This reduces the probability that cleaning liquid contained in the reservoir will enter the at least one feed section. When parking the window cleaning robot, for example on a horizontal installation surface, the unintentional escape of cleaning liquid is largely avoided. The spacing of the feed section relative to the bottom wall can correspondingly limit the entry of cleaning liquid into the at least one fluid line.

The at least one feed section is preferably aligned in a main direction of movement of the window cleaning robot or counter to the main direction of movement. The at least one feed section can be aligned with at least one directional component in or against the main direction of movement, with an inlet opening of the at least one feed section preferably being arranged on its end face. The orientation ensures that cleaning liquid enters the fluid channel depending on the direction of movement of the window cleaning robot. When the direction of travel changes, the loading of the at least one fluid channel with cleaning fluid changes. In practice, this proves to be advantageous in order to be able to better meter the quantity of cleaning liquid that is supplied to the at least one cleaning element.

It proves to be advantageous if two feed sections are provided which are aligned at an angle to one another and open into the discharge section. The two feed sections advantageously define a common plane, which can in particular run parallel to the contact plane. The provision of two feed sections proves to be advantageous in practice. Cleaning liquid can enter the fluid channel via a feed section, and air can escape from the feed channel via the other feed section in order to produce the pressure equalization. This proves to be favorable in order to ensure reliable moistening of the at least one cleaning element.

The angle between the feed sections is advantageously less than 180° and suitably less than about 90°. In an advantageous implementation, the angle between the feed sections can be, for example, approximately 60° to 90°, preferably approximately 70° to 80°. In this case, the angle between the feed sections is considered in particular to be the smaller angle formed between them.

It is advantageous if the feed sections are arranged in such a way that a bisector of the angle between the feed sections is aligned in a main direction of movement of the window cleaning robot or counter to the main direction of movement. As a result of this arrangement of the feed sections, it can be ensured in practice that, when the window cleaning robot changes direction of travel to the left or to the right, cleaning liquid reliably enters the fluid channel via one feed section and air escapes from the feed channel via the other feed section.

The at least one resistance element, in particular the absorber element or filter element, advantageously protrudes into one another in an opening area of the feed sections. This proves to be advantageous, for example, for the humidification of the absorber element or filter element.

From the above description it can be seen in particular that cleaning liquid is supplied to the at least one cleaning element through the at least one fluid channel, preferably depending on the direction of travel of the window cleaning robot with respect to the direction of gravity, for example depending on whether the window cleaning robot moves against or in the direction of gravity.

Optionally, in a window cleaning robot of the type mentioned at the outset, which comprises at least one reservoir for cleaning liquid and at least one fluid channel, via which cleaning liquid can be supplied from the at least one reservoir to the at least one cleaning element to moisten it, it can be provided that a supply of cleaning liquid to the at least one cleaning element through the at least one fluid channel depending on the direction of travel of the window cleaning robot with respect to the direction of gravity. This can represent an independent invention within the scope of the present disclosure.

Based on the above description, it can also be seen in particular that cleaning liquid enters the at least one fluid channel as a function of a change in the direction of travel of the window cleaning robot.

Optionally, in a window cleaning robot of the type mentioned at the outset, which comprises at least one reservoir for cleaning liquid and at least one fluid channel, via which cleaning liquid can be supplied from the at least one reservoir to the at least one cleaning element to moisten it, provision can be made for cleaning liquid to enter the at least one fluid channel takes place depending on a change in the direction of travel of the window cleaning robot. This can represent an independent invention within the scope of the present disclosure.

It has proven to be favorable if the cleaning device comprises two or more fluid channels and if at least one partition wall is arranged between adjacent fluid channels in the at least one reservoir and partially separates spatial areas in the at least one reservoir from one another, with cleaning liquid flowing past the at least one partition wall from one spatial area can flow into a further spatial area and can flow along the at least one partition wall in the direction of an inlet opening of at least one fluid channel. This makes it possible, for example, to conduct cleaning fluid along the partition wall in the direction of the fluid channel when the window cleaning robot changes direction (e.g. left turn and/or right turn), especially when the storage container extends in the transverse direction. The spatial areas are nevertheless in flow connection with one another, so that advantageously as even a distribution of cleaning liquid as possible in the reservoir can be ensured.

It has proven to be advantageous if three or more fluid channels are provided side by side along a longitudinal extension direction of the at least one reservoir and if a respective partition wall is arranged between a fluid channel at the end and a fluid channel positioned directly next to it. In the present case, this can in particular be understood to mean that, for example, fluid channels arranged on the outside in the transverse direction are arranged in spatial regions which are separated from the directly adjacent spatial region by a partition. Since cleaning fluid is consumed during operation of the window cleaning robot, its level in the at least one reservoir drops. The partition walls ensure that the fluid channels arranged at the ends are supplied with a sufficient amount of cleaning liquid to ensure that the at least one cleaning element is moistened over its entire length as far as possible.

It is advantageous if the at least one reservoir has a longitudinal extension and a central area with respect to this, ie in particular a central spatial area if at least two fluid channels are provided opposite one another laterally next to the central area, and if a respective partition wall is arranged between the central area and a fluid channel positioned immediately next to it. This makes it possible to ensure that the fluid channels on the side next to the middle area can still be supplied with sufficient cleaning liquid when cleaning liquid is used up during operation of the window cleaning robot and its level in the reservoir drops.

It can be provided that the at least one fluid channel comprises at least one nozzle element forming its outlet with at least one outlet opening for cleaning liquid. It proves to be advantageous if the resistance element, in particular the absorber element or filter element, is fixed on the fluid channel or in the fluid channel by means of the nozzle element.

The cleaning device favorably comprises a cleaning element holding part, on which the cleaning element is preferably detachably fixed. For example, the cleaning member is fixed to the cleaning member holding part with Velcro. The cleaning element can be detached from the cleaning element holding part for cleaning or replacement.

The cleaning element holding part can be held directly or indirectly, for example via a connecting part, on the at least one reservoir. For example, the cleaning element holding part or the connecting part is suspended via preferably elastically deformable elements which are arranged, for example, on opposite end sides of the cleaning element holding part or connecting part.

Alternatively or in addition, it can be provided that the cleaning element holding part is directly or indirectly resiliently mounted relative to the at least one storage container. Spring elements are provided, for example, which act on the cleaning element holding part with a force directed onto the window surface.

It proves to be advantageous if an outlet of the at least one fluid channel, in particular the nozzle element, is directed towards at least one drip element of the cleaning element holding part on its side facing away from the cleaning element. As a result, cleaning liquid emerging from the fluid channel does not directly wet the at least one cleaning element, but first reaches the at least one dripping element. The dripping element is arranged, for example, at a distance from the fluid channel. The cleaning liquid can be distributed on the drip element in order to ensure a more uniform moistening of the at least one cleaning element.

At least one passage opening for cleaning liquid is preferably formed in the cleaning element holding part on an edge of the at least one dripping element. The cleaning liquid reaches the cleaning element holding part through the at least one passage opening.

Preferably, the cleaning means includes driving means for vibrating the cleaning member holding part. For this purpose, a drive motor can be provided, for example, which is coupled to the cleaning element holding part via an eccentric element and causes it to vibrate. The drive motor is fixed, for example, on at least one reservoir.

The cleaning device advantageously forms a structural unit which comprises the at least one reservoir and which is preferably movably held on a housing of the window cleaning robot. For example, the structural unit can be slidably mounted on the housing, it being possible for the structural unit to be slidable in particular in the transverse direction of the window cleaning robot.

Advantageously, the cleaning device comprises at least one stripping element for stripping downstream of the at least one cleaning element, based on a main direction of movement of the window cleaning robot of cleaning liquid from the window surface. This allows a better cleaning result to be achieved. The pull-off element is designed, for example, as a pull-off lip.

It is advantageous if the window cleaning robot includes a sensor device, by means of which the moisture content of the cleaning element can be determined. For example, two electrodes are provided which contact the at least one cleaning element. By determining a voltage difference or a current flow, it can be determined whether the cleaning element is sufficiently moistened. If this is not the case, the user can be provided with a relevant notification on a notification unit of the window cleaning robot, for example.

In a similar way, it is favorable if the window cleaning robot includes a sensor device, by means of which a filling level of cleaning liquid in the at least one reservoir can be determined. For example, it can be provided that the window cleaning robot is used with a docking station, via which the at least one reservoir can be filled with cleaning liquid. The sensor device can be used to determine that the reservoir is sufficiently filled. The filling process can then be terminated.

The at least one resistance element is advantageously arranged on the cleaning device in an exchangeable manner. This gives the possibility, for example, of replacing the resistance element when it is worn or of changing the wetting properties for the at least one cleaning element by replacing the resistance element.

• mindestens einen Vorratsbehälter zum Bevorraten einer Reinigungsflüssigkeit;
• mindestens ein Reinigungselement (z.B. Reinigungspad), das ausgebildet ist, mit der Reinigungsflüssigkeit befeuchtet zu werden und eine Fensterfläche zu kontaktieren, um Schmutz mithilfe der Reinigungsflüssigkeit abzulösen, wobei der Reinigungsroboter eine Fenster-Eingriffsseite (z.B. Kontaktseite) aufweist, die ausgebildet ist, mit der Fensterfläche in Eingriff zu stehen, um deren Reinigung durch den Roboter zu ermöglichen, wobei das mindestens eine Reinigungselement an der Fenster-Eingriffsseite angeordnet ist;
• mindestens eine Leitung (z.B. Fluidleitung) zum Führen der Reinigungsflüssigkeit, wobei zumindest einige der Leitungen Zuführleitungen sind, deren jede zumindest einen Teil mindestens eines Flüssigkeitszuführpfades bereitstellt, wobei jeder Flüssigkeitszuführpfad sich von dem mindestens einen Vorratsbehälter zu dem mindestens einen Reinigungselement erstreckt, wobei ein Hoch-Impedanzbereich in der mindestens einen Zuführleitung für jeden Flüssigkeitszuführpfad angeordnet ist;
• mindestens eine Pumpe für Luft, die dazu ausgebildet ist, eine Luft-Druckdifferenz über jeden Hoch-Impedanzbereich bereitzustellen;
• wobei, für jeden Flüssigkeitszuführpfad, der entsprechende Hoch-Impedanzbereich ausreichend Impedanz bereitstellt für die Strömung von Reinigungsflüssigkeit entlang des betroffenen Flüssigkeitszuführpfades, so dass sich, in Abwesenheit der Luft-Druckdifferenz, Reinigungsflüssigkeit in der Umgebung des Hoch-Impedanzbereichs in der mindestens einen Zuführleitung für den Flüssigkeitszuführpfad akkumuliert; und
• wobei die Luft-Druckdifferenz ausreichend ist, um die Reinigungsflüssigkeit, die in der Umgebung des Hoch-Impedanzbereichs akkumuliert ist, durch den betreffenden Hoch-Impedanzbereich und zu dem mindestens einen Reinigungspad zu treiben.

The above description discloses in particular an embodiment of a window cleaning robot according to the invention, comprising:

• at least one reservoir for storing a cleaning liquid;
• at least one cleaning element (e.g. cleaning pad) that is designed to be moistened with the cleaning liquid and to contact a window surface in order to detach dirt using the cleaning liquid, the cleaning robot having a window engagement side (e.g. contact side) that is designed to engaging a window surface to allow the robot to clean it, the at least one cleaning member being located on the window engaging side;
• at least one line (e.g. fluid line) for conducting the cleaning liquid, at least some of the lines being feed lines, each of which provides at least part of at least one liquid feed path, each liquid feed path extending from the at least one storage container to the at least one cleaning element, a high Impedance range is arranged in the at least one supply line for each liquid supply path;
• at least one air pump configured to provide an air pressure differential across each high-impedance region;
• wherein, for each liquid supply path, the corresponding high-impedance region provides sufficient impedance for the flow of cleaning liquid along the affected liquid supply path such that, in the absence of the air pressure difference, cleaning liquid in the vicinity of the high-impedance region in the at least one supply line for the liquid supply path accumulated; and
• wherein the air pressure differential is sufficient to force the cleaning liquid accumulated in the vicinity of the high-impedance area through the relevant high-impedance area and to the at least one cleaning pad.

The resistance range provided by the at least one resistance element can be viewed in particular as a high-impedance range.

Figur 1:

eine perspektivische Darstellung eines erfindungsgemäßen Fensterreinigungsroboters;

Figur 2:

eine Draufsicht auf eine Kontaktseite mit einer Fensterfläche des Fensterreinigungsroboters aus Figur 1;

Figur 3:

ein schematisches Blockdiagramm des Fensterreinigungsroboters aus Figur 1;

Figur 4:

eine Draufsicht auf eine Reinigungseinrichtung des Fensterreinigungsroboters aus Figur 1;

Figur 5:

eine Schnittansicht längs der Linie 5-5 in Figur 4;

Figur 6:

eine perspektivische Darstellung der Reinigungseinrichtung aus Figur 5, wobei eine Deckenwand eines Gehäuses nicht dargestellt ist;

Figur 7:

eine vergrößerte Darstellung von Detail A in Figur 6;

Figur 8:

eine Draufsicht auf eine Schnittdarstellung von Detail B in Figur 6, wobei die Schnittlinie längs der Linie 8-8 in Figur 5 verläuft:

Figur 9:

eine perspektivische Darstellung der Reinigungseinrichtung aus Figur 4;

Figur 10:

eine Detaildarstellung in Schnittansicht längs der Linie 10-10 in Figur 4;

Figur 11:

eine Schnittansicht längs der Linie 11-11 in Figur 4; und

Figur 12:

eine Darstellung entsprechend Figur 5 bei einer andersartigen Ausführungsform einer Reinigungsvorrichtung.

The following description of preferred embodiments of the invention, in conjunction with the drawing, serves to explain the invention in more detail. Show it:

Figure 1:

a perspective view of a window cleaning robot according to the invention;

Figure 2:

a top view of a contact side with a window surface of the window cleaning robot figure 1 ;

Figure 3:

Figure 12 shows a schematic block diagram of the window cleaning robot figure 1 ;

Figure 4:

a plan view of a cleaning device of the window cleaning robot figure 1 ;

Figure 5:

a sectional view taken along line 5-5 in figure 4 ;

Figure 6:

a perspective view of the cleaning device figure 5 , wherein a top wall of a housing is not shown;

Figure 7:

an enlarged view of detail A in figure 6 ;

Figure 8:

a plan view of a sectional view of detail B in figure 6 , with the line of intersection along the line 8-8 in figure 5 runs:

Figure 9:

a perspective view of the cleaning device figure 4 ;

Figure 10:

a detailed sectional view taken along line 10-10 in figure 4 ;

Figure 11:

a sectional view taken along line 11-11 in figure 4 ; and

Figure 12:

a representation accordingly figure 5 in a different embodiment of a cleaning device.

The figures 1 and 2 show an advantageous embodiment of a window cleaning robot according to the invention, designated overall by the reference numeral 10, hereinafter robot 10. The robot 10 is designed to be self-propelled and self-steering and enables the autonomous cleaning of a window surface of a window not shown in the drawing. The robot 10 is therefore usually used to clean a vertically oriented window surface.

The robot 10 includes a housing 12 which houses an attachment device 14 for adhering to the window surface, a drive device 16 for moving over the window surface, a control device 18, a pump unit 20 and a first cleaning device 22 . The configuration of the robot 10 as far as the sticking to the window surface, the method and the function of the first cleaning device 22 is concerned is, for example, in detail in FIG EP 3 181 027 A1 described. For the function of the fastening device 14, the drive device 16, the control device 18, the pump unit 20 and the first cleaning device 22, reference is made to the above publication. The functionality of the components described above is only briefly outlined.

The fastening device 14, of which the pump unit 20 is a component, serves on the one hand to ensure that the robot 10 adheres to the window surface during the cleaning movement. For this purpose, the fastening device 14 comprises a sealing element 24 which encloses a suction chamber 26 which can be subjected to negative pressure, it being possible for the negative pressure to be provided by means of a further pump unit 28 .

So that the robot 10 can adhere permanently to the window surface, the fastening device 14 in the present case comprises two suction bodies 30, designed as suction cups. The suction bodies 30 can be subjected to negative pressure by the pump unit 20, as a result of which the robot 10 can adhere so firmly to the window surface that it does not detach itself from it for a longer period of time, for example several hours.

For locomotion, the robot 10 includes the drive device 16, which can include drive wheels 32 and castors 34, for example. During the cleaning movement, the robot 10 usually moves along a main movement direction H. The main movement direction H is a forward direction of the robot 10 and runs in its longitudinal direction. A transverse direction Q of the robot 10 is aligned transversely to the main direction of movement H ( figures 1 and 2 ).

Accordingly, the robot 10 has a front side 36 and a rear side 38, these details relating to the main direction of movement H.

The robot 10 can have a navigation device 40 which, like the fastening device 14 and the drive device 16, is operatively connected to the control device 18 ( figure 3 ).

Furthermore, the robot 10 includes a device 42 for providing electrical energy, which can include, for example, at least one preferably rechargeable battery. The presence of a power cord is also conceivable. The device 42 is coupled to the control device 18, as is an operating and notification device 44 for an operator.

The first cleaning device 22 and the second cleaning device 46 explained below are part of a cleaning system 48 which is coupled to the control device 18 .

The first cleaning device 22 includes a cleaning roller 50 which is aligned in the transverse direction Q and is arranged near the front side 36 . Dirt on the window surface can be removed with cleaning elements of the cleaning roller 50, for example cleaning bristles.

The robot 10 has a contact side 52 which, when used as intended, faces the window surface to be cleaned. figure 2 Figure 12 shows the robot 10 looking at the contact face 52. At the contact face 52, the robot defines a contact plane 54 which, when attached to the window face, is coincident with the plane defined thereby. The figures 5 and 10 to 12 schematically show the position of the contact plane 54 when the robot 10 is used as intended.

While dry cleaning of the window surface is carried out with the first cleaning device 22, the second cleaning device 46 enables it to be wet cleaned. In relation to the main direction of movement H, the first cleaning device 22 is positioned in front of the second cleaning device 46 so that areas of the window surface to be cleaned are first covered by the first cleaning device 22 and then by the second cleaning device 46 .

In particular, the second cleaning device 46 is arranged on the rear side 38, or it defines the rear side 38 through its position on the housing 12.

In the following, reference is made in particular to the Figures 4 to 9 on the configuration of the second cleaning device 46, which forms a structural unit of the robot 10.

As already mentioned, the window cleaning robot 10 according to the invention comprises at least one reservoir for a cleaning liquid, at least one moistenable cleaning element and at least one fluid channel, via which the cleaning liquid from the at least one reservoir can be supplied to the at least one cleaning element in order to moisten it. In the present case, the cleaning device 46 comprises a reservoir 56, a cleaning element 58 and six fluid channels 60, in which case the respective number of these components could also be different.

Overall, the cleaning device 46 is designed to extend longitudinally in the transverse direction Q and has a housing 62 that extends in the transverse direction Q, the extension of which in the longitudinal direction of the robot 10 is significantly less than in the transverse direction Q. Accordingly, in the cleaning device 46, the reservoir 56 and the Cleaning element 58 has an extension in the transverse direction Q. The housing 62 is held movably on the housing 12 of the robot 10 and is preferably mounted so that it can be displaced in the transverse direction Q. This improves the capabilities of the robot 10 for cleaning near edges, for example on window frames.

The reservoir 56 with an interior space 64 is formed in the housing 62 . A lower wall 66, an upper wall 68 and a peripheral side wall 70 of the housing 62 delimit the reservoir 56. This position or orientation information relates to the assumption that the robot 10 is aligned with the contact side 52 perpendicular to the direction of gravity and serves to To facilitate understanding of the invention based on the present description and the drawing. It is understood that when the robot 10 is used on a vertically oriented window surface, the "bottom" and "top" properties for the walls 66, 68 and "side wall" for the wall 70 do not correspond to the actual orientation with respect to a direction of gravity because these depend on the direction of travel of the robot 10. However, it can be defined that the lower wall 66, which forms a bottom wall of the reservoir 56 in the context of the present explanation, has a smaller distance to the contact plane 54 than the upper wall 68. The side wall 70 runs in sections transversely to the contact plane 54 ( figure 5 ).

A recess 72 is formed on the housing 62 on the side of the lower wall 66 facing away from the interior space 64 . The recess 72 extends over its entire length along the transverse direction Q and is delimited in the longitudinal direction of the robot 10 by extensions of the side wall 70 .

In the area of the recess 72, a cleaning element holding part 74 (hereinafter holding part 74) and a connecting part 76 are accommodated, each of which extends substantially over the entire length of the housing 62 in the transverse direction Q.

The holding part 74 serves to hold the cleaning element 58, which in the present case is designed in the form of a cloth. The cleaning element 58 can be releasably fixed to the holding part 74, for example by means of a Velcro fastener. This gives the possibility of removing the cleaning element 58 for cleaning or replacing it with a different type of cleaning element, for example to adapt to the window surface.

The holding part 74 and the connecting part 76 are connected to one another, in the present case, for example, by latching. Passage areas 78 of the holding part 74 and 80 of the connecting part 76 are in each case aligned with one another. In the present case, the passage areas 78, 80 are each designed like a dome.

The number of passage areas 78 corresponds to that of the fluid channels 60; accordingly, there are six passage areas 78, 80 in each case. The fluid channels 60 and the passage areas 78, 80 are each arranged laterally next to one another in the transverse direction Q. In a middle area 82 of the cleaning device 46, based on the transverse direction Q, no fluid channel 60 and no passage area 78, 80 is arranged.

On the opposite sides of the central area 82 there are three fluid channels 60 and passage areas 78, 80 respectively. On each side, the fluid channels 60 on the one hand and the dome areas 78, 80 on the other hand are positioned equidistant from one another. Regarding the middle range 82, the arrangement is mirror-symmetrical with respect to a plane of symmetry perpendicular to the contact plane 54, which runs in the longitudinal direction of the robot 10. Due to the identical configuration of fluid channels 60 and passage areas 78, 80, only one of these components is discussed in each case.

The connecting part 76 and, via this, the holding part 74 and the cleaning element 58 are held on the housing 62 . For this purpose, the cleaning device 46 has elastically deformable elements 86 arranged on mutually opposite end sections 84 of the connecting part 76 ( figure 10 ). The connecting part 76 is fixed hanging on the housing 62 by means of the corresponding coupling elements 88 , 90 via the elements 86 . Due to the deformability of the elements 86, however, the connecting part 76 and thus the cleaning element 58 can move relative to the housing 62. In particular, the cleaning element 58 can be exposed to vibrations, as explained below, which lead to relative movement with respect to the housing 62 and improve the cleaning of the window surface.

In the following, reference is made in particular to the Figures 5 to 9 the structure and functioning of the reservoir 56 and the fluid channels 60 are discussed.

The reservoir 56 can, for example, have an inlet 92 ( figures 6 and 11 ) a cleaning liquid can be supplied. The cleaning liquid is, in particular, water to which a cleaning chemical can be added to increase the cleaning effect. The inlet 92 can, for example, couple to a corresponding outlet of a docking station (not shown) for the robot 10 . When the robot 10 is in the docked position, cleaning liquid can flow from a reservoir of the docking station into the reservoir 56 .

The robot 10 has a sensor device 94 which has, for example, two electrodes 96 in the interior 64 . The electrodes 96 can in particular be coupled to the control device 18, which can be part of the sensor device 94. A voltage difference and/or a current flow depending on the level of the cleaning liquid in the reservoir 56 can be detected by the sensor device 94 . For example, a relevant signal can be transmitted to the docking station in order to end the filling process.

Cleaning liquid can flow and reach via the fluid channel 60 from the interior 64 in the direction of the cleaning element 58 . For this purpose, the fluid channel has at least one feed section. In the present case, two feed sections 98, 100 are provided. In addition, the fluid channel 60 includes a dispensing portion 102 which is aligned with the cleaning element. An angle between the discharge section 102 and a respective feed section 98, 100 is approximately 90°.

The dispensing portion 102 extends through an opening 104 in the bottom wall 66 and projects into the recess 72 . The dispensing section 102 reaches through an opening 106 of the passage area 80 and, in the present case, projects approximately to an opening 108 of the passage area 78 ( figure 5 ). The fluid channel 60 includes a contact flange 110 for resting against the lower wall 66.

The release section is preferably aligned transversely and in particular perpendicularly to the contact plane 54 .

A resistance element 112 is accommodated in the discharge section 102 . In this case, each of the fluid channels 60 is assigned a resistance element 112 .

The resistance element 112 is formed separately from the fluid channel 60 and is inserted into the dispensing section 102 in a form-fitting manner. It is elongated oriented along the dispensing portion 102 .

In the present case, the resistance element 102 is a moistenable absorber element 114, which can absorb cleaning liquid and release it again. Accordingly, the absorber element 114 can become soaked with cleaning liquid. By applying a force, in particular a pressure, cleaning liquid can be released again.

Cleaning liquid can be absorbed by capillary action. In a corresponding manner, the cleaning liquid can be released from the absorber element 114 under capillary action.

It is favorable that the expansion of the absorber element 114 when absorbing liquid can be limited by the positioning in the fluid channel 60 .

In an advantageous embodiment, the absorber element 114 consists of a cotton-based material. For example, the use of a so-called dental cotton roll for the absorber element 114, which is positioned in the oral cavity during dental treatment, has proven to be advantageous.

In the present case, the absorber element 114 protrudes beyond the dispensing section 102 in the direction of the cleaning element 58 . However, this is not mandatory.

The fluid channel 60 includes a nozzle element 116 which forms an outlet 118 of the fluid channel 60 . In the present case, the nozzle element 116 also serves to fix the absorber element 114 to the dispensing section 102 and can be made of an elastic material for this purpose. In the present case, the nozzle element 116 has a plurality of outlet openings 120 which are located within the space enclosed by the passage area 78 ( figures 5 and 9 ).

The holding part 74 comprises a dripping element 122 in the respective passage area 78 which is arranged at a distance from the outlet openings 120 . The Drip element 122 is centrally aligned with respect to dispensing portion 102 . The dripping element 122 is surrounded by an essentially ring-shaped passage opening 124 which is only interrupted by means of webs (not shown) for the application of the dripping element 122 to the holding part 74 .

Cleaning liquid that emerges from the discharge section 102, i.e. that is discharged from the absorber element 114, passes through the outlet openings 120 to the dripping element 122 and from there through the through-opening 124 to the cleaning element 58. In this way, the cleaning liquid over a large area of the cleaning element 58 distributed, especially since a plurality of fluid channels 60 is present. Within the cleaning element 58, further liquid transport can take place via the capillary effect.

The supply sections 98 and 100 already mentioned open out into one another at a mouth area 126 and into the discharge section 102. In the present case, the absorber element 114 protrudes into the mouth area 126 ( figure 8 ).

Cleaning liquid reaches the feed sections 98 up to the absorber element 114. It has proven to be advantageous that a respective inlet of a feed section 98, 100 is arranged at a distance from the lower wall 66. When the robot 10 is positioned with the contact side 52 vertically downward, this limits the amount of cleaning liquid that can enter the fluid channel 60 . This ensures, for example, that no cleaning liquid gets onto the cleaning element 58 when the robot 10 is positioned on a set-up surface (for example a table top).

This is also due in particular to the fact that the absorber element 114 provides resistance to a flow of cleaning liquid through the fluid channel 60 to the cleaning element. This proves to be advantageous for targeted moistening of the cleaning element 58 when the robot 10 is in use.

In the absence of the absorber element 114, cleaning liquid could flow without resistance through the fluid channel 60 to the cleaning element 58 and moisten it. This proves to be problematic because the amount of cleaning liquid dispensed is so large that cleaning liquid remains on the window surface after the robot has driven over it. This can not only impair the cleaning result, but also make it more difficult for the robot 10 to adhere to the window surface when it is driven over again, since the tightness of the suction chamber 26 can no longer be guaranteed.

On the other hand, if an attempt is made to reduce the amount of cleaning liquid discharged by providing the fluid channel with a small cross section, moistening of the cleaning element 58 can fail because no flow is formed at all as a result of the surface tension of the cleaning liquid.

The present, advantageous embodiment enables a structurally simple design of the cleaning device 46 and at the same time offers the possibility of supplying the cleaning element 58 with the required quantity of cleaning liquid.

It has proven to be favorable that two feed sections 98, 100 are provided. An angle 128 is formed between the feed sections 98, 100, for example of approximately 80°. The feed sections 98, 100 are arranged and aligned in such a way that a bisector of the angle 128 runs along the main direction of movement H ( figure 8 ).

Due to the fact that there are two feed sections 98, 100, depending on the orientation of the robot 10, cleaning liquid can get into the fluid channel 60 via one of the feed sections 98, 100, with pressure equalization taking place via the other feed section 98, 100 and air being able to escape. The orientation of the feed sections 98, 100 relative to the main direction of movement ensures that when the direction of travel is changed to the left during the forward movement, cleaning fluid is also supplied to the fluid channel 60, as is the case when the direction of travel is changed to the right during the forward movement.

In addition, the orientation of the feed sections 98, 100 can influence the amount of cleaning liquid that is fed to the fluid channel 60 depending on the direction of travel of the robot 10 with respect to the direction of gravity, with this configuration again being based on the consideration that the robot 10 is usually vertical aligned window surfaces are cleaned. For example, during a movement counter to the direction of gravity (upward in Figure 18), essentially no cleaning liquid is fed to the fluid channel 60; this takes place both in the case of a left turn and in the case of a right turn via one of the feed sections 98, 100 with pressure equalization by the respective other feed section 98 , 100.

In the case of the robot 10, it therefore proves to be advantageous for the cleaning liquid to enter the fluid channel as a function of a change in the direction of travel of the robot 10.

In order to ensure that the cleaning element 58 is moistened as uniformly and reliably as possible, partition walls are arranged in the reservoir 56, which can be formed by the housing 62, for example. In the present case, partition walls 130 are arranged between a respective fluid channel 60 at the end in the transverse direction Q and the fluid channel 60 positioned directly next to it ( figures 6 and 8th ).

The respective partition wall 130 separates spatial areas 132 of the interior space 64 from one another. A respective partition 130 is designed in such a way that cleaning liquid can flow past the partition 130 from one spatial area 132 into the adjacent spatial area 132 . Cleaning liquid can flow along the respective partition wall 130 in the direction of an inlet opening 134 of a feed section 98 or 100 flow. The dividing wall 130 ensures that when the level of the cleaning liquid falls during the operation of the robot 10 there is a sufficient quantity of cleaning liquid in the fluid channels 60 arranged at the end to also reliably moisten the cleaning element 58 at the end.

A partition wall 130 is likewise arranged in each case between the middle region 82 (now viewed in the reservoir 56) and the fluid channels 60 arranged laterally next to it in the transverse direction Q. This ensures that the fluid channels 60 arranged laterally directly next to the middle region 82 are supplied with a sufficient quantity of cleaning liquid.

As already mentioned, the absorber element 114 can be moistened with the cleaning liquid and forms a resistance to the flow through the fluid channel 60. For this reason, the absorber element 114 can also be referred to as a throttle element.

It is particularly advantageous in the robot 10 that cleaning liquid can be applied in a targeted manner by generating a pressure difference across the absorber element 114 . In this case, the pressure is on the upstream side of the absorber element 114 than on the downstream side. In the present case, the pressure difference is provided by means of a pump unit, it being advantageous in order to achieve a structurally simple configuration if the pump unit 20 of the fastening device can be used.

The pump assembly 20 is a membrane pump that can apply negative pressure to the suction body 30 and excess pressure to the interior 64 . For this purpose, the pump unit 20 is flow-connected to the pump unit 20 via a connecting element 136 with a fluid line 138 connected thereto ( figures 2 and 4 ). A valve 140 can be provided, which is assigned to the suction body 30 and can be controlled by the control device 18 . During the cleaning operation the valve 140 must be closed. However, a valve is not absolutely necessary.

The pump assembly 20 can apply gas, such as in particular air, to the interior space 64 and thereby provide an overpressure in the interior space 64 . This leads to a pressure difference across the absorber element 114 because the pressure in the interior space 64 is higher than the ambient pressure on the outlet side of the discharge section 102.

The pump unit 20 is activated in particular in a discrete or pulsed manner. Each pulse can last approximately 10 ms to 50 ms, for example. The duration between successive pulses can be about 1 s.

During operation of the robot 10, the absorber element 114 is moistened with a suitable quantity of cleaning liquid, as explained above. Since the absorber element 114 provides resistance to flow through the fluid passage 60, cleaning fluid will not drip from the absorber element 114 in the absence of the pressure differential.

In contrast, the activation of the pump unit 20 leads to the provision of the pressure difference across the absorber element 114, so that drops of cleaning liquid can be released from the absorber element 114 and, as explained above, can reach the cleaning element 58 via the nozzle element 116 and the drip element 122.

It can be provided that the mode of operation of the pump unit 20 can be adjusted by an operator in order to adjust the amount of cleaning liquid dispensed.

The above configuration enables the cleaning element 58 to be moistened as uniformly as possible, with the amount of cleaning liquid being metered in a targeted manner.

The vibration of the holding part 74 has already been mentioned. For this purpose, the cleaning device 46 comprises a drive device 142 with a drive motor 144. The drive motor 144 is held, for example, on the housing 62 ( figure 11 ). An eccentric element 148 is held eccentrically on a drive shaft 146 of the drive motor 144 . In the present case, the eccentric element 148 is arranged in a form-fitting manner in a receptacle 150 of the connecting part 76 . Under the action of the drive motor 144, the connecting part 76 and with it the holding part 74 are made to vibrate.

The holding part 74 is also spring-loaded in the direction of the window surface. For this purpose, the cleaning device includes spring elements 152, designed as compression springs. The spring elements 152 are supported on dome areas 154 of the housing ( figures 6 and 8th ). The respectively opposite end acts on the connecting part 76 with a spring force directed towards the window area.

The robot 10 includes a further sensor device 156 in order to determine the moisture content of the cleaning element 58 . For example, the sensor device 156 includes electrodes 158 ( figure 9 ). For example, a voltage difference and/or a current flow between the electrodes 158 can be determined by the control device 18, which can be part of the sensor device 156. If it is determined that the cleaning element 58 is not sufficiently moist, a notification can be provided to the user, for example on the notification device 44 .

Downstream of the cleaning element 58 in the main direction of movement H, the cleaning device 46 comprises a stripping element 160. In the present case, the stripping element 160 is configured as a stripping lip 162. The stripping lip 162 extends in the transverse direction Q essentially over the entire width of the housing 62 and allows residual liquid to be removed from the strip window area.

figure 12 shows in one of the figure 5 corresponding manner an embodiment of a cleaning device 170, which can be used instead of the cleaning device 46 in the robot 10 according to the invention. Identical reference symbols are used for features and components that are the same or have the same effect.

In the cleaning device 170, the fluid channel 60 has the discharge section 102 and only one feed section 172. The discharge section 102 and the feed section 172 are oriented at an angle to one another, the angle here being slightly greater than 90° and being approximately 100°. The feed section 172 is aligned, at least in terms of components, approximately parallel to the contact plane 54 and further counter to the main direction of movement H.

An absorber element 114 is also used as the resistance element 112, which in the present case is a cigarette filter, for example.

The fluid channel 60 in the cleaning device 170 is made of an elastically deformable material, for example, and is inserted into the opening 104 .

The nozzle element 116 at the outlet 118 is omitted, but this could also be present.

Claims (15)

1. Window cleaning robot, comprising a fastening device (14) for adhering to a window surface, a drive device (16) for moving over the window surface, a cleaning device (46) for cleaning the window surface, wherein the cleaning device (46; 170) has at least one cleaning element (58) which is arranged on a contact side (52) of the window cleaning robot (10) that faces the window surface during its use, at least one reservoir (56) for cleaning liquid, at least one fluid channel (60) via which the cleaning liquid can be supplied from the at least one reservoir (56) to the at least one cleaning element (58) to moisten it, and at least one resistance element (112) arranged on or in the at least one fluid channel (60) for providing a resistance against a flow of cleaning liquid through the fluid channel (60) from the at least one reservoir (58) to the at least one cleaning element (58), characterized in that the at least one resistance element (112) is liquid-permeable, the at least one resistance element (112) is formed separately from the at least one fluid channel (60) and is arranged thereon or therein, and that the at least one resistance element (112) is or forms an absorber element (114).
2. Window cleaning robot according to Claim 1, characterized in that the cleaning device (46; 170) comprises a plurality of fluid channels (60) and/or that the at least one cleaning element (58) extends transversely to a main movement direction (H) of the window cleaning robot (10) and is designed as a cloth or sponge.
3. Window cleaning robot according to Claim 2, characterized in that at least one of the following applies:

   - the fluid channels (60) are arranged laterally next to one another along an extension direction (Q) of the at least one cleaning element (58);

   - the cleaning device (46; 170) comprises a plurality of resistance elements (112) which are assigned to a particular fluid channel (60);

   - a reservoir (56) is provided, from which cleaning liquid can be supplied to the at least one cleaning element (58) and in particular to the exactly one cleaning element (58) via the plurality of fluid channels (60).
4. Window cleaning robot according to any one of the preceding claims, characterized in that at least one of the following applies:

   - the absorber element (114) is designed to extend longitudinally and is preferably oriented in a running or extension direction of the at least one fluid channel (60);

   - the absorber element (114) consists of a porous material or comprises a porous material;

   - the absorber element (114) comprises passages for the cleaning liquid;

   - the absorber element (114) consists at least in part of a cellulose-based material, a cotton or cotton-based material, a fiber material and/or a polymer material;

   - the absorber element (114) is a dental cotton roll or a cigarette filter.
5. Window cleaning robot according to any one of the preceding claims, characterized in that the window cleaning robot (10) has a pump unit (20) for conveying a gas and for providing a pressure difference via the at least one resistance element (112) such that, when the pressure difference is applied, cleaning liquid flows through the at least one fluid channel (60), preferably the at least one resistance element (112) provides sufficient resistance, and the cleaning liquid, in the absence of the pressure difference, is prevented from flowing through the at least one fluid channel (60).
6. Window cleaning robot according to Claim 5, characterized in that at least one of the following applies:

   - the at least one resistance element (112) provides sufficient resistance so that the cleaning liquid, in the absence of the pressure difference, is prevented from flowing through the at least one fluid channel (60) regardless of the orientation of the window cleaning robot (10) relative to the direction of gravity;

   - the window cleaning robot (10) has a control device (18) for actuating the pump unit (20), and the pump unit (20) can be actuated to provide a discrete or continuous pressure difference;

   - the pump unit (20) is in fluidic connection with the at least one reservoir (56) through at least one fluid line (138), and an overpressure can be generated in the at least one reservoir (56) by means of the pump unit (20);

   - the fastening device (14) comprises a suction body (30) for drawing the window cleaning robot (10) to the window surface, and the pump unit (20) is part of the fastening device (14) of the window cleaning robot (10) for applying negative pressure to the suction body (30), wherein the control device (18) is in operative connection in particular with at least one valve (140) in order to selectively fluidically connect the pump unit (20) to the suction body (30).
7. Window cleaning robot according to any one of the preceding claims, characterized in that the at least one fluid channel (60) has at least one feed section (98, 100) via which the cleaning liquid enters the at least one fluid channel (60), and a delivery section (102) arranged at an angle to the at least one feed section (98, 100), via which the cleaning liquid can be guided in the direction of the at least one cleaning element (58), wherein the at least one feed section (98, 100) and the delivery section (102) are oriented at an angle to each other, in particular the angle is approximately 90°.
8. Window cleaning robot according to Claim 7, characterized in that at least one of the following applies:

   - the at least one feed section (98, 100) is oriented parallel or substantially parallel to the contact plane (54) of the window cleaning robot (10) defined on the contact side (52), and/or the delivery section (102) is oriented transversely or substantially transversely to the contact plane (54);

   - the at least one absorber element (114) is arranged in the delivery section (102);

   - the at least one feed section (98, 100) is arranged in the at least one reservoir (56) or engages therein in such a way that the at least one feed section (98, 100) is arranged at a distance from a base wall (66) of the at least one reservoir (56) when the window cleaning robot (10) is oriented with the contact side (52) vertically downward;

   - the at least one feed section (98, 100) is oriented in a main movement direction (H) of the window cleaning robot (10) or counter to the main movement direction (H);

   - two feed sections (98, 100) which are oriented at an angle to one another and open into the delivery section (102) are provided.
9. Window cleaning robot according to Claim 8, characterized in that at least one of the following applies:

   - the angle between the feed sections (98, 100) is approximately 60° to 90°, preferably approximately 70° to 80°;

   - the feed sections (98, 100) are arranged such that an angle bisector of the angle (128) between the feed sections (98, 100) is aligned in a main movement direction (H) of the window cleaning robot (10) or counter to the main movement direction (H);

   - the at least one absorber element (114) projects into a mouth region (126) of the feed sections (98, 100).
10. Window cleaning robot according to any one of the preceding claims, characterized in that at least one of the following applies:

    - cleaning liquid is supplied to the at least one cleaning element (58) through the at least one fluid channel (60) depending on the direction of travel of the window cleaning robot (10) with respect to the direction of gravity;

    - the at least one fluid channel (60) is designed such that the entry of cleaning liquid into the at least one fluid channel (60) is dependent on a change in direction of travel of the window cleaning robot (10);

    - the cleaning device (46; 170) comprises two or more fluid channels (60), and at least one partition wall (130) is arranged between adjacent fluid channels (60) in the at least one reservoir (56) and partially separates spatial regions (132) in the at least one reservoir (56) from one another, wherein cleaning liquid can flow past the at least one partition wall (130) from one spatial region (132) into another spatial region (132), and can flow along the at least one partition wall (130) in the direction of an inlet opening (134) of at least one fluid channel (98, 100).
11. Window cleaning robot according to Claim 10, characterized in that three or more fluid channels (60) arranged laterally next to one another along a direction of longitudinal extension (Q) of the at least one reservoir (56) are provided, wherein a respective partition wall (130) is arranged between an end-side fluid channel (60) and a fluid channel (60) positioned directly adjacent thereto, and/or the at least one reservoir (56) has a longitudinal extension and a central region (82) with respect thereto, at least two fluid channels (60) are provided opposite one another laterally next to the central region (82), wherein a respective partition wall (130) is arranged between the central region (82) and a fluid channel (60) directly adjacent thereto.
12. Window cleaning robot according to any one of the preceding claims, characterized in that the at least one fluid channel (60) comprises at least one nozzle element (116) which forms its outlet (118) and has at least one outlet opening (120) for cleaning liquid, and/or the cleaning device (46; 170) comprises a cleaning element holding part (74) on which the cleaning element (58) can preferably be detachably fixed.
13. Window cleaning robot according to Claim 12, characterized in that at least one of the following applies:

    - an outlet (118) of the at least one fluid channel (60), in particular the nozzle element (116), is directed toward at least one drip element (122) of the cleaning element holding part (74) at its side facing away from the cleaning element (58);

    - at least one passage opening (124) for cleaning liquid in the cleaning element holding part (74) is formed on an edge of the at least one drip element (122);

    - the cleaning device (46; 170) comprises a drive device (142) in order to cause the cleaning element holding part (74) to vibrate.
14. Window cleaning robot according to any one of the preceding claims, characterized in that the cleaning device (46; 170) forms an assembly comprising the at least one reservoir (56), which is preferably movably held on a housing (12) of the window cleaning robot (10), and/or the cleaning device (46; 170) comprises, in relation to a main movement direction (H) of the window cleaning robot (10), at least one squeegee element (160) for removing liquid from the window surface downstream from the at least one cleaning element (58).
15. Window cleaning robot according to any one of the preceding claims, characterized in that at least one of the following applies:

    - the window cleaning robot (10) comprises a sensor device (156) by means of which the moisture of the cleaning element (58) can be determined;

    - the window cleaning robot comprises a sensor device (94) by means of which a fill level of cleaning liquid in the at least one reservoir (56) can be determined;

    - the at least one resistance element (112) is interchangeably arranged on the cleaning device (46; 170).

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