WO2018162737A1 - Window cleaning robot - Google Patents

Abstract

The invention relates to a window cleaning robot comprising a securing 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 window cleaning robot (10) contact side (52) facing the window surface when the robot is used; at least one storage container (56) for cleaning fluid; at least one fluid channel (60) via which the cleaning fluid can be supplied from the at least one storage container (56) to the at least one cleaning element (58) in order to humidify same; and at least one resistor element (112) which is arranged on or in the at least one fluid channel (60) for providing a resistance against a flow of cleaning fluid through the fluid channel (60) from the at least one storage container (58) to the at least one cleaning element (58).

Description

 WINDOW CLEANING ROBOT

The present invention relates to a window cleaning robot comprising a fixing device for adhering to a window surface, a driving device for moving over the window surface and a cleaning device for cleaning the window surface, wherein the cleaning device comprises at least one cleaning element, which at a contact side of the window cleaning robot, in its use the window surface is facing, is arranged.

Such a window cleaning robot is for example in the

EP 3,181,027 AI described. The window cleaning robot enables autonomous cleaning of a window surface, i. H. in particular a vertically oriented surface. The window cleaning robot is self-propelled and self-steering. By means of a vacuum-operated fastening device, the window cleaning robot can adhere to the window surface, and the drive device enables the window cleaning robot to move on the window surface, wherein the window cleaning robot moves along a main movement direction 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 cleaner in the main moving direction with a cleaning brush for releasing coarse dirt from the window surface. Following the cleaning brush in the main movement direction, the window cleaning robot comprises the cleaning device mentioned at the outset with at least one cleaning element. The cleaning member, such as a cleaning cloth, is disposed on the contact side of the window cleaning robot facing the window surface in use thereof. At the contact side, the window cleaning robot defines a contact plane or - -

Touch level that coincides with a plane defined by the window area.

EP 3 181 027 A1 describes that the window surface can be wetted with a cleaning liquid before cleaning. Alternatively, it is possible to wet the cleaning element with the cleaning liquid. With the cleaning element dirt can be removed from the window surface.

Object of the present invention is to provide a window cleaning robot of the type mentioned, in which a user-friendly humidification of the cleaning element is made possible with a view to a better cleaning result.

This object is achieved in a window cleaning robot of the aforementioned type according to the invention that the window cleaning robot comprises at least one reservoir for cleaning fluid, at least one fluid channel, via the cleaning fluid from the at least one reservoir the at least one cleaning element to the humidification can be supplied, and at least one on or in the at least one fluid channel arranged resistance element for providing a resistance to a flow of cleaning fluid through the fluid channel from the at least one reservoir to the at least one cleaning element.

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 with it a supply of cleaning fluid, so that the user is spared a wetting of 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. As the window cleaning robot usually on is used - a vertically oriented window surface, the amount of cleaning liquid, which is applied via the at least one cleaning element on the window surface, of importance. First, 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 remaining on the window surface after cleaning and, upon re-running, may 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 the at least one fluid channel. The resistance element, which in the present case can also be referred to as a throttle element, forms a resistance with which a flow of the cleaning fluid through the fluid channel to the cleaning element can be influenced, in particular inhibited and, if necessary, completely prevented. By means of the at least one resistance element, it is possible to dose the amount of cleaning fluid supplied to the at least one cleaning element in a structurally relatively simple design of the cleaning device such that preferably as much cleaning fluid as possible and as little as necessary are applied through the resistance region formed by the resistance element can.

It is favorable in terms of a structurally simple embodiment, if the at least one resistance element is designed passive, for example, without moving parts. Although conceivable is the use of at least one controllable valve, but for ease of construction, the cleaning device can preferably make do without a valve on at least one fluid channel.

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

It is particularly advantageous if the cleaning fluid can be temporarily absorbed by the resistance element, e.g. physically and / or chemically, and then can be discharged again, wherein the resistance element serves as a kind of buffer for cleaning fluid.

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

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

Advantageously, the fluid channels are configured identically.

It proves to be favorable if the cleaning device comprises a plurality of resistance elements, which are assigned to a respective fluid channel, wherein the resistance elements are preferably configured identically.

In an advantageous embodiment, exactly one storage container is provided, from which cleaning liquid can be supplied to the at least one cleaning element and in particular to exactly one cleaning element via the plurality of fluid channels. Accordingly, it is favorable if the cleaning device comprises exactly one storage container and exactly one cleaning element. For example, a plurality of fluid channels are provided.

The exactly one storage container is designed to extend longitudinally, for example, in the transverse direction of the window cleaning robot. In the presence of - - A plurality of storage containers can be provided that they are arranged laterally side by side in the transverse direction.

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

The main direction of movement can also be considered as the forward direction of the window cleaning robot, along which main direction of movement or forward direction of the window cleaning robot usually traverses over the window area. The main movement direction can be arbitrarily aligned relative to a direction of gravity (or vertical), depending on the travel of the window cleaning robot, in particular against the direction of gravity up, in the direction of gravity down, perpendicular to the direction of gravity or oblique to the direction of gravity.

In an advantageous embodiment it can be provided that the at least one resistance element is formed by a cross-sectional constriction of the at least one fluid channel. The fluid channel, including its inlet and / or its outlet, may have a cross-sectional constriction which impedes the passage of cleaning fluid through the fluid channel to form a resistance region.

In another advantageous embodiment, it is favorable if the at least one resistance element is formed separately from the at least one fluid channel and arranged on or in this. Thereby, the structural design can be simplified, and depending on the requirements of the window cleaning robot, for example, there is the possibility to provide resistance elements of different types that provide different resistances. For example, the resistance element may be disposed at or positioned in an inlet or outlet of the fluid channel. Advantageously, the resistance element is arranged in a form-fitting manner in the fluid channel. - -

It proves to be favorable if substantially the entire resistor is provided by the at least one resistance element against a flow of cleaning fluid through the at least one fluid channel.

It is advantageous if 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, although possible, but not mandatory. The absorber element or filter element is in particular liquid permeable, so that the flow of cleaning fluid through the at least one fluid channel is at least inhibited. For this purpose, the absorber element or filter element may have intrinsic passages and / or a porous nature.

The absorber element makes it possible to absorb and hold a certain amount of cleaning fluid (for example, physically and / or chemically), and it can effectively serve for temporarily storing the cleaning fluid while forming the resistance region. When the absorber element comes in contact with the cleaning liquid, it propagates therein, for example, under the capillary action. Cleaning liquid can escape from the absorber element again, but is prevented by the capillary action. However, in particular under the action of pressure on the absorber element, cleaning liquid may be released from the absorber element, as explained below. This makes it possible to achieve a targeted moistening of the cleaning element.

It can be provided that the absorber element or filter element is configured 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 comprises a porous material. The porous texture - - The absorber element or filter element allows the flow of cleaning fluid, but opposed the flow through the fluid channel resistance.

It can be provided that the absorber element or filter element comprises passages for the cleaning fluid. The passages may have a relatively small cross-section, so that the passage of cleaning liquid is inhibited.

In an advantageous embodiment, the absorber element or filter element at least partially consists 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 advantageous if the absorber element or filter element is a dental floss roller. Such a dental floss roller, for example made of cotton-based material, is used in dentistry for receiving saliva and cooling fluid during drilling. In practice, such an absorber element or filter element proves to be advantageous for use in the window cleaning robot.

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

It is favorable when the window cleaning robot has a pumping unit for conveying a gas, for example air, and for providing a pressure difference across the at least one resistance element such that cleaning fluid flows through the at least one fluid channel when the pressure difference is applied, the at least one resistance element advantageously having sufficient resistance provides that the cleaning liquid, in the absence of the pressure difference, the flow through the at least - - A fluid channel is prevented. With the pump unit, a pressure difference can be provided, whereby in particular on different sides (upstream and downstream) of the at least one resistance element different pressures occur and the pressure on the upstream side is higher than on the downstream side. When the pressure difference is applied, the cleaning liquid can flow through the at least one fluid channel, so that the inhibiting effect of the resistance element is overcome under the effect of the pump unit such that a minimum quantity 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 in the absence of the pressure difference preferably does not flow through the at least one cleaning liquid, under the action of the resistance element.

In the above-mentioned embodiments, for example, in the absence of the pressure difference, cleaning liquid can be "collected" at the at least one resistance element, for example by absorption in the absorber element. If the pressure difference occurs via the resistance element, the cleaning fluid is pumped through the at least one fluid channel and the at least one cleaning element supplied, for example, by dissolving cleaning fluid 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, flows through the at least one fluid channel independently of the orientation of the window cleaning robot relative to one

Direction of gravity is hindered. As a result, unintentional leakage of the at least one storage container can be prevented, for example, when the window cleaning robot is positioned over the contact side on a horizontal footprint, 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 be used - - Even with horizontally positioned window cleaning robot moistened.

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

The pump unit is preferably controllable in order to provide a discrete pressure difference across the at least one resistance element. For example, at intervals of about one second, pressure differentials may be provided by the pumping unit, with a respective surge being able to stop, for example, for about 10 ms to 50 ms. It can be provided that an operator can set the intervals and / or the duration of the pressure surges to ensure optimum humidification of the at least one cleaning element.

In another embodiment, it can be provided that the pump unit can be acted upon continuously to provide the pressure difference.

It is favorable if the pump unit is in fluid communication with the at least one storage container via at least one fluid line and if an overpressure in the at least one storage container can be generated by means of the pump unit. The pump unit is, for example via at least one hose line with the at least one reservoir in fluid communication. The interior of the reservoir can be subjected to overpressure, whereby a pressure difference over the at least one resistance element is formed. As a result of the overpressure, cleaning liquid can be pumped through the fluid line, whereby, for example, cleaning liquid dissolves from the absorber element, as described above.

It has already been mentioned at the beginning that the window cleaning robot comprises a fastening device. It is advantageous if the fastening device comprises a suction body and if the pump unit is part of the - -

Fastening device of the window cleaning robot is, for example, to apply to the absorbent body with negative pressure. For example, the pump unit may evacuate a space between the absorbent body and the window surface, or cause deformation of the absorbent body, so that the window cleaning robot may adhere to the window surface.

It proves to be favorable if the control device is in operative connection with, in particular, at least one valve in order to bring the pumping unit into selective fluid communication with the absorbent body. Accordingly, it can be provided that the absorbent body serves to secure the window cleaning robot to the window surface, apart from the normal cleaning operation, during which the window cleaning robot moves over the window surface. For "firmly sucking" on the window surface, the control device can actuate the at least one valve. During the cleaning operation, the at least one valve to the absorbent body is closed, for example, whereby the pump unit as mentioned above can provide the pressure difference across the at least one resistance element. However, it may also be provided that a valve is not required and may be omitted.

For the above purpose, for example, a diaphragm pump is suitable as a suitable pump unit, wherein the suction side may be in communication with the absorbent body and the pressure side, for example, with the at least one reservoir. If only discrete pressure surges are delivered to provide the pressure difference, this may be sufficient for wetting the cleaning element, wherein the absorbent body is not yet activated, however.

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, deviating from the above explanations, no pumping unit is available or used to provide a pressure difference.

In an advantageous embodiment, it proves to be advantageous 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 the cleaning liquid in the direction of the at least one cleaning element is feasible, wherein the at least one feed section and the discharge section are aligned at an angle to each other.

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

Conveniently, the at least one feed section is aligned parallel or substantially parallel to the contact plane of the window cleaning robot defined on the contact side. The aforementioned contact plane defined by the window cleaning robot may 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 aligned transversely or substantially transversely to the contact plane.

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

As already mentioned, the at least one resistance element is advantageously particularly moistenable and suitable for receiving and holding a certain amount of cleaning fluid. In particular, under the action of the pump unit and the resulting pressure difference, a drop of cleaning liquid can form, which detaches from the resistance element and moisten the at least one cleaning element.

It is advantageous if the at least one feed section is arranged in or engages in the at least one storage container such that the at least one feed section is arranged vertically downwards at a distance to a bottom wall of the at least one storage container when the window cleaning robot is oriented. This reduces the likelihood that cleaning fluid contained in the reservoir will enter the at least one feed section. When parking the window cleaning robot, for example, on a horizontal footprint, the unintentional leakage of cleaning fluid is largely avoided. The distance of the feed section relative to the bottom wall can accordingly restrict the entry of cleaning liquid into the at least one fluid line.

Preferably, the at least one feed section is aligned in a main movement direction of the window cleaning robot or counter to the main movement direction. With at least one directional component, the at least one feed section can be aligned in or counter to the main movement direction, wherein an inlet opening of the at least one feed section is preferably arranged on its end face. The alignment ensures that cleaning fluid enters the fluid channel depending on the direction of movement of the window cleaning robot. When changing the direction of travel, the admission of the at least one fluid channel changes with cleaning fluid. This proves to be advantageous in practice in order to better dose the amount of cleaning fluid, which is supplied to the at least one cleaning element. - -

It proves to be favorable if two feeding sections oriented at an angle to one another and opening into the delivery section are provided. The two feed sections advantageously define a common plane, which in particular can 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 other feed section to remove pressure from the supply channel. This proves to be favorable in order to ensure reliable humidification of the at least one cleaning element.

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

It is advantageous if the feed sections are arranged such that an angle 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 Zuführabschnitte can be ensured in practice that reliably enters both in a change of direction of the window cleaning robot to the left and to the right via a feed section cleaning liquid into the fluid channel and escapes through the respective other feed air from the supply channel.

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

It can be seen in particular from the above description that a supply of cleaning liquid 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 in the introduction, which comprises at least one reservoir for cleaning fluid and at least one fluid channel via which cleaning fluid from the at least one reservoir can be supplied to the at least one cleaning element for humidification, it may be provided that a supply of cleaning fluid for at least one cleaning element through the at least one fluid channel therethrough depending on the direction of travel of the window cleaning robot with respect to the direction of gravity. This may constitute an independent invention in the context of the present disclosure.

In particular, it can also be seen from the above description that an entry of cleaning liquid into the at least one fluid channel is effected as a function of a change in the direction of travel of the window cleaning robot.

Optionally, in the case of a window cleaning robot of the type mentioned above, which comprises at least one reservoir for cleaning fluid and at least one fluid channel, via which cleaning fluid is supplied from the at least one reservoir to the at least one cleaning element for humidification, it may be provided that an entry of cleaning fluid into the at least one fluid channel is dependent on a change of direction of the window cleaning robot. This may constitute an independent invention in the context of the present disclosure. - -

It proves to be advantageous if the cleaning device comprises two or more fluid channels and if at least one partition between adjacent fluid channels is arranged in the at least one reservoir and space regions in at least one reservoir partially separated from each other, wherein cleaning liquid on the at least one partition wall of a space area flow into a further space region and can flow along the at least one partition wall in the direction of an inlet opening of at least one fluid channel. As a result, for example, in the case of a supply direction change (for example, left-hand curve and / or right-hand curve) of the window cleaning robot, it is possible to guide cleaning liquid along the dividing wall in the direction of the fluid channel, in particular in the case of a reservoir extending in the transverse direction. The space areas are still in fluid communication with each other, so that advantageously as equal as possible distribution of cleaning fluid in the reservoir can be ensured.

It proves to be favorable if three or more fluid channels are arranged laterally next to one another along a longitudinal extension direction of the at least one storage container and if a respective dividing wall is arranged between an end-side fluid channel and a fluid channel positioned directly next to it. In the present case, this may in particular be understood to mean that, for example, fluid channels arranged in the transverse direction are arranged in spatial regions which are separated from the immediately adjacent spatial region via a dividing wall. Since cleaning liquid is consumed during the operation of the window cleaning robot, its level drops in at least one storage container. By the partitions ensures that the end disposed fluid channels are acted upon with a sufficient amount of cleaning liquid to ensure humidification of the at least one cleaning element as possible over its entire length.

It is advantageous if the at least one storage container has a longitudinal extension and with respect to this central region, d. H . insbesonde- A central space region is provided when at least two fluid channels are provided opposite one another laterally adjacent to the middle region, and when a respective partition wall is arranged between the central region and a fluid channel positioned immediately adjacent thereto. As a result, it is possible to ensure that sufficient fluid can be applied to the fluid channels laterally next to the middle region even if cleaning fluid is consumed 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 absorber element or filter element, is fixed by means of the nozzle element on the fluid channel or in the fluid channel.

Conveniently, the cleaning device comprises a cleaning element holding part, on which the cleaning element is preferably releasably fixed. For example, the cleaning element is fixed to the cleaning element holding part via a hook-and-loop fastener. For cleaning or replacement, the cleaning element can be released from the cleaning element holding part.

The cleaning element holding part can be held directly or indirectly, for example via a connecting part, on which at least one storage container. For example, a suspension of the cleaning element holding part or the connecting part 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 additionally, it may be provided that the cleaning element holding part is mounted directly or indirectly resiliently relative to the at least one storage container. For example, spring elements are provided, which act on the cleaning element holding part with a directed force on 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 onto at least one dripping element of the cleaning element holding part on its side facing away from the cleaning element. As a result, cleaning fluid leaving the fluid channel does not readily 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. At the drip element, the cleaning liquid can be distributed to ensure a more uniform humidification of at least one cleaning element.

Preferably, at least one passage opening for cleaning liquid is formed in the cleaning element holding part at one edge of the at least one dripping element. The cleaning liquid passes through the at least one passage opening on the cleaning element holding part.

The cleaning device preferably comprises a drive device in order to set the cleaning element holding part in vibration. For this purpose, for example, a drive motor may be provided, which is coupled via an eccentric with the cleaning element holding part and this is vibrated. The drive motor is fixed, for example, on at least one reservoir.

Conveniently, the cleaning device forms an assembly comprising the at least one reservoir, which is preferably held movably on a housing of the window cleaning robot. It can be provided, for example, a displaceable mounting of the assembly on the housing, wherein the assembly can be displaced, in particular in the transverse direction of the window cleaning robot.

Conveniently, the cleaning device, based on a main movement direction of the window cleaning robot, the at least one cleaning element downstream at least one peel-off element for removal - - of cleaning liquid from the window surface. As a result, a better cleaning result can be achieved. The peel-off element is designed, for example, as a peel-off lip.

It is advantageous if the window cleaning robot comprises a sensor device by means of which the humidity 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 can be determined whether the cleaning element is sufficiently moistened. If this is not the case, the user can, for example, be provided with an indication of this at a notification unit of the window cleaning robot.

Similarly, it is favorable if the window cleaning robot comprises a sensor device by means of which a filling level of cleaning liquid in the at least one storage container can be determined. For example, it may be provided that the window cleaning robot is used with a docking station, via which the at least one storage container can be filled with cleaning liquid. Based on the sensor device can be determined that the reservoir is sufficiently filled. The filling process can then be ended.

Conveniently, the at least one resistance element is arranged interchangeably on the cleaning device. This gives, for example, the possibility of replacing the resistance element in the event of wear or of changing the wetting properties for the at least one cleaning element by exchanging the resistance element.

The above description discloses in particular an embodiment of a window cleaning robot according to the invention, comprising: at least one storage container for storing a cleaning liquid; at least one cleaning member (eg, cleaning pad) adapted to be moistened with the cleaning liquid and to contact a window surface to detach dirt with the cleaning liquid, the cleaning robot having a window engaging side (eg, contact side) is configured to engage with the window surface to allow its cleaning by the robot, wherein the at least one cleaning element is arranged on the window engagement side; at least one conduit (eg, fluid conduit) for carrying the cleaning fluid, wherein at least some of the conduits are supply conduits, each providing at least a portion of at least one fluid delivery path, each fluid delivery path extending from the at least one reservoir to the at least one purifying member a high-impedance region is disposed 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 fluid delivery path, the respective high impedance region provides sufficient impedance for the flow of cleaning fluid along the affected fluid delivery path such that, in the absence of the air pressure differential, cleaning fluid in the vicinity of the high impedance region in the at least one delivery conduit for the Liquid supply path accumulated; and wherein the air pressure difference is sufficient to drive the cleaning liquid accumulated in the vicinity of the high-impedance region through the high-impedance region concerned and to the at least one cleaning pad.

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

The following description of preferred embodiments of the invention is used in conjunction with the drawings for a more detailed explanation of the invention. Show it :

Figure 1: a perspective view of a window cleaning robot according to the invention;

Figure 2: a plan view of a contact side with a window surface of

 Window cleaning robot of Figure 1;

Figure 3 is a schematic block diagram of the window cleaning robot of Figure 1;

FIG. 4 shows a plan view of a cleaning device of the window cleaning robot from FIG. 1;

Figure 5 is a sectional view taken along line 5-5 in Figure 4;

Figure 6: a perspective view of the cleaning device

 Figure 5, wherein a ceiling wall of a housing is not shown;

Figure 7 is an enlarged view of detail A in Figure 6;

FIG. 8 shows a top view of a sectional view of detail B in FIG. 6, the section line extending along the line 8--8 in FIG. 5:

FIG. 9 shows a perspective view of the cleaning device

 Figure 4;

FIG. 10: a detail view in a sectional view along the line 10-10 in FIG

Figure 4; - -

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

FIG. 12: a representation corresponding to FIG. 5 for a different type

 Embodiment of a cleaning device.

Figures 1 and 2 show a total occupied by the reference numeral 10 advantageous embodiment of a window cleaning robot according to the invention, hereinafter robot 10. The robot 10 is designed self-propelled and self-steering and allows autonomous cleaning a window surface of a window, not shown in the drawing. The robot 10 is therefore usually used for cleaning a vertically oriented window area.

The robot 10 includes a housing 12 that accommodates a fastener 14 for adhering to the window surface, a drive device 16 for moving over the window surface, a controller 18, a pump assembly 20, and a first cleaner 22. The configuration of the robot 10, insofar as the adhesion to the window surface, the method and the function of the first cleaning device 22 is concerned, is described in detail, for example, in EP 3 181 027 A1. 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 is thus made to the above publication. The operation of the components described above will be briefly outlined.

The fastening device 14, of which the pump unit 20 is a part, on the one hand serves 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 pressurized with negative pressure, wherein the negative pressure can be provided by means of a further pumping unit 28. - -

In order for the robot 10 to adhere permanently to the window surface, the fastening device 14 in the present case comprises two absorbent bodies 30 configured as suction cups. The suction body 30 can be acted upon by the pump unit 20 with negative pressure, whereby the robot 10 can adhere so firmly to the window surface that it does not dissolve for a longer period, for example several hours.

For locomotion, the robot 10 includes the drive device 16, which may include, for example, drive wheels 32 and castors 34. Usually, the robot 10 moves during the cleaning movement along a main movement direction H. The main movement direction H is a forward direction of the robot 10 and extends in the longitudinal direction thereof. Transverse to the main movement direction H, a transverse direction Q of the robot 10 is aligned (FIGS. 1 and 2).

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

The robot 10 may have a navigation device 40, which, like the fastening device 14 and the drive device 16, are in operative connection with the control device 18 (FIG. 3).

Furthermore, the robot 10 comprises a device 42 for providing electrical energy, which may comprise, for example, at least one preferably rechargeable battery. It is also conceivable the presence of a power cord. The device 42 is coupled to the control device 18, as well as an operating and pointing 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 comprises a cleaning roller 50, which is aligned in the transverse direction Q and disposed 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, in the intended use, faces the window surface to be cleaned. FIG. 2 illustrates the robot 10 with respect to the contact side 52. At the contact side 52, the robot defines a contact plane 54 which, when adhered to the window surface, coincides with the plane defined by the latter. FIGS. 5 and 10 to 12 show schematically the position of the contact plane 54 when the robot 10 is used as intended.

While a dry cleaning of the window surface is performed with the first cleaning device 22, the second cleaning device 46 enables its wet cleaning. Relative to the main movement direction H, the first cleaning device 22 precedes the second cleaning device 46, so that areas of the window area to be cleaned are first detected 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 by its position on the housing 12, the back 38th

In the following, with reference in particular to FIGS. 4 to 9, the configuration of the second cleaning device 46, which forms a structural unit of the robot 10, will be discussed.

As already mentioned, the window cleaning robot 10 according to the invention comprises at least one reservoir for a cleaning liquid, at least one wettable cleaning element and at least one fluid channel, - - About the cleaning liquid from the at least one reservoir the at least one cleaning element to the humidification is supplied. In the present case, the cleaning device 46 comprises a reservoir 56, a cleaning element 58 and six fluid channels 60, wherein the respective number of these components could also be different.

Overall, the cleaning device 46 is formed longitudinally in the transverse direction Q and has a transversely extending Q extending housing 62, whose extension in the longitudinal direction of the robot 10 is substantially less than in the transverse direction Q. Accordingly, in the cleaning device 46, the reservoir 56 and the Cleaning element 58 an extension in the transverse direction Q on. The housing 62 is held movably on the housing 12 of the robot 10 and preferably mounted displaceably in the transverse direction Q. This improves the capabilities of the robot 10 for near-clean cleaning, for example on window frames.

In the housing 62 of the reservoir 56 is formed with an interior 64. A bottom wall 66, a top wall 68 and a circumferential side wall 70 of the housing 62 define the storage container 56. These position or orientation statements refer here assuming alignment of the robot 10 with the contact side 52 perpendicular to the direction of gravity and serves to To facilitate understanding of the invention with reference to the present description and the drawings. It should be understood that in use of the robot 10 on a vertically oriented window surface, the "down" and "up" characteristics for the walls 66, 68 and "sidewall" for the wall 70 do not match the actual orientation with respect to a direction of gravity because of this depend on the direction of travel of the robot 10. However, it can be defined that the lower wall 66, which in the context of the present explanation forms a bottom wall of the storage container 56, has a smaller distance from the contact plane 54 than the upper wall 68. The side wall 70 extends in sections transversely to the contact plane 54 (FIG. 5). , - -

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

In the region of the recess 72, a cleaning element holding part 74 (hereinafter holding part 74) and a connecting part 76 are received, each extending 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 is designed cloth-shaped in the present case. The cleaning element 58 is detachably fixable on the holding part 74, for example by means of a hook-and-loop fastener. This makes it possible to remove the cleaning element 58 for cleaning or to exchange it for a different cleaning element, for example for adaptation to the window surface.

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

The number of passage regions 78 corresponds to that of the fluid channels 60, and accordingly there are six passage regions 78, 80 in each case. The fluid channels 60 and the passage regions 78, 80 are in each case arranged laterally next to each other in the transverse direction Q. In a central region 82 of the cleaning device 46, with respect to the transverse direction Q, no fluid channel 60 and no passage region 78, 80 are arranged.

On the opposite sides of the central region 82 are each three fluid channels 60 and passage areas 78, 80 are present. 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 each other. With regard to the mean The arrangement is mirror-symmetrical with respect to a plane of symmetry perpendicular to the contact plane 54 that extends in the longitudinal direction of the robot 10. Due to the identical design 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 opposite end sections 84 of the connecting part 76 (FIG. 10). About the elements 86, the connecting part 76 is suspended from the housing 62 by means of corresponding coupling members 88, 90 fixed. 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 may be exposed to vibrations as described below, which lead to the relative movement with respect to the housing 62 and improve the cleaning of the window area.

In the following, reference will be made, in particular to FIGS. 5 to 9, to the construction and functioning of the reservoir 56 and the fluid channels 60.

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

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

Cleaning fluid can flow out of the interior 64 in the direction of the cleaning element 58 via the fluid channel 60 and pass. 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 comprises a delivery section 102, which is aligned with the cleaning element. An angle between the discharge portion 102 and a respective supply portion 98, 100 is about 90 °.

The delivery section 102 passes through an opening 104 in the lower wall 66 and projects into the recess 72. In this case, the discharge section 102 passes through an opening 106 of the passage region 80 and in the present case projects approximately as far as an opening 108 of the passage region 78 (FIG. 5). For abutment against the bottom wall 66, the fluid channel 60 includes a abutment flange 110.

The dispensing section is preferably aligned transversely and in particular perpendicular to the contact plane 54.

In the delivery section 102, a resistance element 112 is received. 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 inserted in a form-fitting manner into the delivery section 102. It is elongated, being aligned along the dispensing section 102. - -

In the present case, the resistance element 102 is a humidable absorber element 114, which can absorb cleaning fluid and release it again. The absorber element 114 can accordingly be soaked with cleaning fluid. By applying a force, in particular a pressure, cleaning fluid can be dispensed again.

The inclusion of cleaning fluid can be done under capillary action. In a corresponding manner, the discharge of cleaning liquid from the absorber element 114 can take place under capillary action.

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

In an advantageous embodiment, the absorber element 114 is made of a cotton-based material. For example, the use of a so-called tooth wadding 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 projects beyond the discharge section 102 in the direction of the cleaning element 58. However, this is not mandatory.

The fluid channel 60 comprises a nozzle element 116, which forms an outlet 118 of the fluid channel 60. In the present case, the nozzle element 116 serves at the same time for fixing the absorber element 114 to the delivery 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 (FIGS. 5 and 9).

The holding part 74 comprises at the respective passage region 78 a drip element 122, which is arranged at a distance from the outlet openings 120. The - -

Drip element 122 is aligned centrally with respect to the delivery section 102. The drip element 122 is surrounded by a substantially annular passage opening 124, which is interrupted only by the use of the drip element 122 on the holding part 74 by means of webs (not shown).

Cleaning liquid exiting from the discharge portion 102, i. which is discharged from the absorber element 114 passes through the outlet openings 120 on the dripping element 122 and from there through the passage opening 124 on the cleaning element 58. In this way, the cleaning liquid is distributed over a large area of the cleaning element 58, especially since a plurality of fluid channels 60 present is. Within the cleaning element 58, a further liquid transport via the capillary action can take place.

The already mentioned feed sections 98 and 100 open into one another and into the discharge section 102 at an orifice region 126. In the present case, the absorber element 114 projects into the mouth region 126 (FIG. 8).

Cleaning liquid passes into the feed sections 98 to the absorber element 114. It proves to be advantageous that a respective inlet of a feed section 98, 100 is arranged at a distance from the lower wall 66. When positioning the robot 10 with the contact side 52 vertically downwards, this limits the amount of cleaning liquid that can enter the fluid channel 60. This ensures, for example, that no cleaning liquid reaches the cleaning element 58 when positioning the robot 10 on an installation surface (for example, table surface).

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

In the absence of the absorber element 114 cleaning fluid 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 applied is so great that after passing the robot on the window surface cleaning liquid remains. This can not only affect the cleaning result, but also complicate the adhesion of the robot 10 on the window surface when driving over again, since the tightness of the suction chamber 26 can not be guaranteed.

On the other hand, if an attempt is made to reduce the amount of cleaning fluid discharged by providing the fluid channel with a small cross-section, humidification of the cleaning element 58 may fail due to the surface tension of the cleaning liquid generating no flow at all.

The present advantageous embodiment allows a structurally simple embodiment of the cleaning device 46 and at the same time offers the possibility to supply the cleaning element 58 with the required amount of cleaning liquid.

It proves to be favorable that two feed sections 98, 100 are provided. Between the feed sections 98, 100 an angle 128 is formed, for example of approximately 80 °. In this case, the feed sections 98, 100 are arranged and aligned such that an angle bisector of the angle 128 runs along the main movement direction H (FIG. 8).

Due to the fact that two supply sections 98, 100 are present, depending on the orientation of the robot 10, cleaning fluid can reach the fluid channel 60 via one of the feed sections 98, 100, pressure equalization taking place via the respective other feed section 98, 100 and air being able to escape. The orientation of the feed sections 98, 100 relative to the main - - Movement ensures that when changes in direction, which are carried out in the forward movement to the left around the fluid channel 60 cleaning fluid is supplied as well as changes in direction, which are executed in the forward movement to the right.

In addition, the orientation of the feed sections 98, 100 can influence which amount of cleaning fluid is supplied to the fluid channel 60 with respect to the direction of gravity, depending on a direction of travel of the robot 10. This configuration is again based on the consideration that with the robot 10 usually vertically oriented windows are cleaned. For example, substantially no cleaning liquid is supplied to the fluid channel 60 during a movement opposite to the direction of gravity (in FIG. 18); this takes place in the case of a left turn as well as a right turn via one of the feed sections 98, 100 under pressure equalization by the respective other feed section 98 , 100.

Therefore, it proves to be favorable for the robot 10 that the entry of cleaning liquid into the fluid channel takes place as a function of a change in the direction of travel of the robot 10.

In order to ensure the most uniform and reliable humidification of the cleaning element 58, 56 partition walls are arranged in the reservoir, which may be formed for example by the housing 62. In the present case, dividing walls 130 are arranged between a respective fluid channel 60, which ends in the transverse direction Q, and the fluid channel 60 positioned directly next to it (FIGS. 6 and 8).

The respective partition wall 130 separates space regions 132 of the interior 64 from one another. A respective dividing wall 130 is such that cleaning liquid can flow past the dividing wall 130 from one space area 132 into the adjacent space area 132. Along the respective partition wall 130, cleaning liquid can be directed in the direction of an inlet opening - -

134 of a feed section 98 or 100 flow. By the partition wall 130 it is ensured that with falling level of the cleaning liquid during operation of the robot 10 at the end disposed fluid channels 60, a sufficient amount of cleaning liquid is present in order to moisturize the cleaning element 58 end reliable.

Between the middle region 82 (now considered in the storage container 56) and the laterally arranged in the transverse direction Q fluid channels 60, a partition wall 130 is also arranged in each case. In this case, it is ensured that the fluid channels 60 arranged laterally next to the central region 82 are supplied with a sufficient amount 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. The absorber element 114 can therefore also be referred to as a throttle element.

Particularly advantageous in the case of the robot 10 is 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 on the upstream side of the absorber element 114 is on the downstream side. The pressure difference is provided in the present case by means of a pump unit, wherein it is to achieve a structurally simple embodiment of advantage when the pump unit 20 of the fastening device can be used.

The pump unit 20 is a diaphragm pump, which can act on the absorbent body 30 with negative pressure and the interior 64 with overpressure. For this purpose, the pump unit 20 is connected via a connection element 136 with fluid line 138 connected thereto to the pumping unit 20 in fluid communication (FIGS. 2 and 4). It can be provided a valve 140 which is associated with the absorbent body 30 and can be controlled by the control device 18. During the cleaning operation can - - The valve 140 to be closed. However, a valve is not essential.

The pump unit 20 can the interior 64 with gas, in particular air, act on and thereby provide an overpressure in the interior 64. This results in a pressure difference across the absorber element 114, because the pressure in the interior space 64 is higher than the ambient pressure at the outlet side of the discharge section 102.

The pumping unit 20 is activated in particular discretely or pulsed. For example, a respective pulse may take approximately 10 ms to 50 ms. The duration between successive pulses may be about 1 second.

In operation of the robot 10, the absorber element 114 is moistened with an appropriate amount of cleaning fluid as discussed above. Since the absorber element 114 forms a resistance to the flow through the fluid channel 60, cleaning liquid does not drip from the absorber element 114 in the absence of the pressure difference.

In contrast, the activation of the pumping unit 20 leads to the provision of the pressure difference via 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 dripping element 122.

It may be provided that the operation of the pumping unit 20 can be adjusted by an operator to adjust the amount of cleaning liquid discharged.

The above configuration allows the most uniform moistening of the cleaning element 58, wherein the amount of cleaning liquid is selectively metered. - -

The vibration of the holding part 74 has already been addressed. For this purpose, the cleaning device 46 comprises a drive device 142 with a drive motor 144. The drive motor 144 is held on the housing 62, for example (FIG. 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 this the holding part 74 is vibrated.

The holding part 74 is further spring-loaded in the direction of the window surface. For this purpose, the cleaning device comprises spring elements 152, configured as compression springs. The spring elements 152 are supported on dome areas 154 of the housing (FIGS. 6 and 8). The respective opposite end acts on the connecting part 76 with a spring force directed onto the window surface.

The robot 10 comprises a further sensor device 156 in order to determine the humidity of the cleaning element 58. For example, the sensor device 156 comprises electrodes 158 (FIG. 9). By the control device 18, which may be part of the sensor device 156, for example, a voltage difference and / or a current flow between the electrodes 158 can be determined. If it is determined that the cleaning element 58 is not sufficiently moist, the user can be provided with an indication, for example, at the pointer 44.

Downstream of the cleaning element 58 in the main movement direction H, the cleaning device 46 comprises a stripping element 160. The stripping element 160 is configured here as a stripping lip 162. The stripping lip 162 extends in the transverse direction Q over substantially the entire width of the housing 62 and allows residual liquid from the Strip window surface. - -

FIG. 12 shows, in a manner corresponding to FIG. 5, 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. For identical or equivalent features and components identical reference numerals are used.

In the cleaning device 170, the fluid channel 60 has the delivery section 102 and only one delivery section 172. The delivery section 102 and the delivery section 172 are oriented at an angle to one another, wherein the angle here is slightly greater than 90 ° and approximately 100 °. The feed section 172 is, at least component-wise, aligned approximately parallel to the contact plane 54 and also opposite to the main movement direction H.

The resistance element 112 is likewise an absorber element 114, which in the present case is, for example, a cigarette filter.

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

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

Claims

A window cleaning robot comprising attachment means (14) for adhering to a window surface, drive means (16) for moving over the window surface, cleaning means (46) for cleaning the window surface, the cleaning means (46; 170) at least cleaning member (58) comprising, at a contact surface (52) of the window cleaning robot (10) facing the window surface in use, at least one reservoir (56) for cleaning fluid, at least one fluid channel (60) over the cleaning fluid from the at least one Reservoir (56) is supplied to the at least one cleaning element (58) for its humidification, and at least one at or in the at least one fluid channel (60) arranged resistance element (112) for providing a resistance to a flow of cleaning fluid through the fluid channel (60) from at least one storage container (58) for at least ens a cleaning element (58). 2. Window cleaning robot according to claim 1, characterized in that the at least one resistance element (112) is liquid-permeable. 3. Window cleaning robot according to claim 1 or 2, characterized in that the cleaning device (46; 170) comprises a plurality of fluid channels (60). 4. Window cleaning robot according to claim 3, characterized in that the fluid channels (60) are arranged laterally side by side along a Erstre- ckungsrichtung (Q) of the at least one cleaning element (58). 5. window cleaning robot according to claim 3 or 4, characterized in that the cleaning device (46; 170) a plurality of counterclaim Standing members (112) associated with a respective fluid channel (60). 6. Window cleaning robot according to one of claims 3 to 5, characterized in that a storage container (56) is provided, from which the at least one cleaning element (58) and in particular exactly one cleaning element (58) via the plurality of fluid channels (60 ) Cleaning fluid can be supplied. 7. Window cleaning robot according to one of the preceding claims, characterized in 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. 8. Window cleaning robot according to one of the preceding claims, characterized in that the at least one resistance element (112) by a cross-sectional constriction of the at least one fluid channel (60) is formed. 9. Window cleaning robot according to one of claims 1 to 7, characterized in that the at least one resistance element (112) is formed separately from the at least one fluid channel (60) and arranged on or in this. 10. Window cleaning robot according to claim 9, characterized in that the at least one resistance element (112) is an absorber element (114) or forms. 11. Window cleaning robot according to claim 10, characterized in that the absorber element (114) is configured elongate and is preferably aligned in a direction or extension direction of the at least one fluid channel (60). 12. Window cleaning robot according to claim 10 or 11, characterized in that for the absorber element (114) at least one of the following applies: the absorber element (114) consists of a porous material or comprises a porous material; the absorber element (114) comprises passages for the cleaning fluid; the absorber element (114) consists at least partially of a cellulose-based material, a cotton or cotton-based material, a fiber material and / or a polymer material. 13. Window cleaning robot according to one of claims 10 to 12, characterized in that the absorber element (114) is a tooth wad roll or a cigarette filter. 14. Window cleaning robot according to 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 across the at least one resistance element (112) such that at applied pressure difference cleaning fluid through the at least one fluid channel (60) flows through, preferably that the at least one resistance element (112) provides sufficient resistance that the cleaning fluid, in the absence of the pressure difference, is prevented from flowing through the at least one fluid passage (60). 15. Window cleaning robot according to claim 14, characterized in that the at least one resistance element (112) provides sufficient resistance that the cleaning liquid, in the absence of WO 2018/162737 _ 3g _ PCT / EP2018 / 055953 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 a direction of gravity. 16. Window cleaning robot according to claim 14 or 15, characterized in that the window cleaning robot (10) has a control device (18) for driving the pump unit (20) and that the pump unit (20) is controllable to provide a discrete or continuous pressure difference. 17. Window cleaning robot according to one of claims 14 to 16, characterized in that the pump unit (20) with the at least one reservoir (56) via at least one fluid line (138) is in fluid communication and that by means of the pumping unit (20) an overpressure in at least one storage container (56) can be generated. 18. window cleaning robot according to one of claims 14 to 17, characterized in that the fastening device (14) comprises a suction body (30) for sucking the window cleaning robot (10) on the window surface and that the pump unit (20) part of the fastening device (14) of the Window cleaning robot (10) is for applying the suction body (30) with negative pressure, wherein the control device (18) in particular with at least one valve (140) is operatively connected to selectively bring the pump unit (20) in fluid communication with the absorbent body (30) , 19. Window cleaning robot according to one of the preceding claims, characterized in that the at least one fluid channel (60) at least one feed section (98, 100), via the cleaning liquid enters the at least one fluid channel (60), and at an angle to at least one Supply section (98, 100) arranged discharge section (102) through which cleaning fluid in the direction of the at least one cleaning element (58) is feasible, wherein the mini- WO 2018/162737 _ ₄ g _ PCT / EP2018 / 055953 least one feed section (98, 100) and the discharge portion (102) are aligned at an angle to one another, in particular that the angle is approximately 90 °. 20. window cleaning robot according to claim 19, characterized in that the at least one feed section (98, 100) parallel or substantially parallel to the contact side (52) defined contact plane (54) of the window cleaning robot (10) is aligned and / or that the discharge section (102) is aligned transversely or substantially transversely to the contact plane (54). 21. Window cleaning robot according to claim 19 or 20, characterized in that the at least one resistance element (112), in particular the absorber element (114), in the discharge section (102) is arranged. 22. Window cleaning robot according to one of claims 19 to 21, characterized in that the at least one feed section (98, 100) is arranged in such a manner in at least one storage container (56) or engages in that the at least one feed section (98, 100) at Orientation of the window cleaning robot (10) with the contact side (52) vertically downward at a distance from a bottom wall (66) of the at least one storage container (56) is arranged. 23. Window cleaning robot according to one of claims 19 to 22, characterized in that the at least one feed section (98, 100) in a main movement direction (H) of the window cleaning robot (10) or against the main movement direction (H) is aligned. 24. Window cleaning robot according to one of claims 19 to 23, characterized in that two angularly aligned and in the discharge section (102) opening feed sections (98, 100) are provided. 25. Window cleaning robot according to claim 24, characterized in that the angle between the feed sections (98, 100) is approximately 60 ° to 90 °, preferably approximately 70 ° to 80 °. 26. Window cleaning robot according to claim 24 or 25, characterized in that the feed sections (98, 100) are arranged so that an angle bisector of the angle (128) between the feed sections (98, 100) in a main movement direction (H) of the window cleaning robot (10 ) or against the main direction of movement (H) is aligned. 27. Window cleaning robot according to one of claims 24 to 26, characterized in that the at least one resistance element (112), in particular the absorber element (114) in an orifice region (126) of the feed sections (98, 100) protrudes into one another. 28, window cleaning robot according to one of the preceding claims, characterized in that a supply of cleaning liquid to at least one cleaning element (58) through the at least one fluid channel (60) therethrough depending on the direction of travel of the window cleaning robot (10) with respect to the direction of gravity. 29. Window cleaning robot according to one of the preceding claims, characterized in that the at least one fluid channel (60) is designed such that an entry of cleaning liquid into the at least one fluid channel (60) depends on a change of direction of the window cleaning robot (10). 30. window cleaning robot according to one of the preceding claims, characterized in that the cleaning device (46; 170) comprises two or more fluid channels (60) and that in at least one reservoir (56) at least one partition wall (130) between adjacent hard fluid channels (60) is arranged and space regions (132) in the at least one reservoir (56) partially separated from each other, wherein cleaning liquid on the at least one partition wall (130) pass from one space area (132) in another space area (132) and along the at least one partition wall (130) can flow in the direction of an inlet opening (134) of at least one fluid channel (98, 100). 31, window cleaning robot according to claim 30, characterized in that three or more along a longitudinal direction (Q) of the at least one reservoir (56) laterally juxtaposed fluid channels (60) are provided and that a respective partition (130) between an end-side fluid channel (60 ) and a fluid channel (60) positioned immediately adjacent thereto. 32. Window cleaning robot according to claim 30 or 31, characterized in that the at least one storage container (56) has a longitudinal extent and with respect to this central region (82), that at least two fluid channels (60) opposite each other laterally adjacent to the central region (82). are provided, and that a respective partition wall (130) between the central region (82) and a directly adjacent positioned fluid channel (60) is arranged. 33. Window cleaning robot according to one of the preceding claims, characterized in that the at least one fluid channel (60) at least one nozzle (116) forming the outlet (118) comprising at least one outlet opening (120) for cleaning fluid. 34. Window cleaning robot according to one of the preceding claims, characterized in that the cleaning device (46; 170) comprises a cleaning element holding part (74) on which the cleaning element (58) is preferably detachably fixable. 35. A window cleaning robot according to claim 34, characterized in that an outlet (118) of the at least one fluid channel (60), in particular the nozzle element (116), on an at least one dripping element (122) of the cleaning element holding part (74) on the cleaning element (58 ) facing away from the side. 36. Window cleaning robot according to claim 35, characterized in that 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 dripping element (122). 37. A window cleaning robot according to any one of claims 34 to 36, characterized in that the cleaning device (46; 170) comprises a drive device (142) for causing the cleaning element holding part (74) to vibrate. 38. Window cleaning robot according to one of the preceding claims, characterized in that the cleaning device (46; 170) forms a unit comprising the at least one storage container (56), which is preferably held movably on a housing (12) of the window cleaning robot (10). 39. Window cleaning robot according to one of the preceding claims, characterized in that the cleaning device (46; 170), based on a main movement direction (H) of the window cleaning robot (10), the at least one cleaning element (58) downstream at least one stripping element (160) for peeling of cleaning liquid from the window surface. 40. Window cleaning robot according to one of the preceding claims, characterized in that the window cleaning robot (10) comprises a sensor device (156) by means of which the moisture of the cleaning element (58) can be determined. 41. Window cleaning robot according to one of the preceding claims, characterized in that the window cleaning robot comprises a sensor device (94) by means of a level of cleaning liquid in at least one reservoir (56) can be determined. 42. Window cleaning robot according to one of the preceding claims, characterized in that the at least one resistance element (112) is arranged exchangeably on the cleaning device (46; 170).