TW201804949A - Wet-type cleaning apparatus with cleaning element and wetting device for achieving optimal cleaning effect with as little liquid usage as possible - Google Patents

Abstract

The present invention relates to a wet-type cleaning apparatus (1) and, more particularly, to a wet mopping device, which comprises a cleaning element (2), in particular a cleaning roller rotatable about a rotating axle (3); and a wetting device (4) for applying liquid to the cleaning element (2). In order to achieve optimal cleaning effect with as little liquid usage as possible, the wetting device (4) is proposed to have a guide surface (6) for liquid, which is disposed above a liquid flow path and between a liquid nozzle ( 5) and the cleaning element (2), and which is displaceable relative to the cleaning element (2) in particular, wherein the guide surface (6) is configured relative to the fluid discharge direction (x) of the liquid nozzle (5) at an angle (<alpha>) between 90 degrees and 170 degrees, in particular between 90 degrees and 105 degrees, such that the liquid accelerated and discharged from the liquid nozzle (5) to the guide surface (6) spreads when impacting on the guide surface (6), and then reaches the cleaning element (2) along the guide surface (6) due to the force of gravity.

Description

Wet cleaning equipment with cleaning element and wetting device

The invention relates to a wet cleaning device, in particular a wet wiping device, having a cleaning element, in particular a cleaning roller rotatable around a rotation axis, and a wetting device for applying liquid to the cleaning element.

In addition, the present invention relates to a method of operating a wet cleaning apparatus in which a liquid is applied to a cleaning element by a wetting device.

In the prior art, wet cleaning equipment and methods of operating wet cleaning equipment have been known to me.

DE 102 29 611 B3, for example, discloses a wet cleaning device having a wiper body that can be driven to rotate around a rotation axis, wherein a cleaning liquid is obtained from a storage tank and a nozzle is arranged along the direction of the rotation axis of the wiper body. , Spray the cleaning solution on the surface of the wiper. The wiper body moistened in this way moves on the surface to be cleaned during the wiping operation, wherein the wiper body collects dirt on the surface to be cleaned.

The disadvantage of this method of wetting the wiper is that it requires a large amount of liquid to wet the entire wiper. In addition, the wiping body is unevenly wetted, causing at least a portion of the surface to be cleaned to be too wet rather than only slightly wetted.

Based on the foregoing prior art, the object of the present invention is to improve the wet cleaning equipment of the aforementioned type so that the surface to be cleaned can be obtained with as little liquid as possible. To the best cleaning.

To achieve the above object, the present invention proposes that the wetting device has a guide surface for liquid, which is disposed between the liquid nozzle and the cleaning element on the flow path of the liquid, and is particularly displaceable relative to the cleaning element. The guide surface is arranged at an angle between 90 ° and 170 °, especially between 90 ° and 105 ° with respect to the liquid discharge direction of the liquid nozzle, so that the liquid is expelled from the liquid nozzle to the guide. The liquid on the guide surface expands when hitting the guide surface, and reaches the cleaning element along the guide surface under the action of gravity.

According to the invention, this wet cleaning device has a guide surface on which liquid can flow towards the cleaning element. The term "liquid" as used in the present invention also refers to steam, droplets, sprays or the like. Since then, the liquid discharged from the liquid nozzle is no longer directly applied to the cleaning element, but is first applied to the guide surface, and then from there to the cleaning element. To this end, the liquid nozzle is arranged relative to the guide surface, so that the liquid exiting the liquid nozzle is accelerated in the direction of the liquid ejection into the guide surface and flows there toward the cleaning element. After the liquid hits the guide surface, the liquid jet expands into a liquid film. The liquid leaving the liquid nozzle is advantageously accelerated by the pump and is ejected from the liquid nozzle in the direction of the liquid which is deviated from the vertical direction. The liquid essentially hits the guide surface in this direction, wherein the force exerted by the pump on the liquid is sufficient to make the liquid reach the guide surface. The liquid generates a liquid spot on the guide surface. With the liquid spot as a starting point, the liquid is divided into several parts and moves substantially in radial directions in various directions, for example, it is also opposite to the direction of gravity. As the distance between the liquid and the liquid nozzle increases, it becomes more vertical due to the influence of the direction of gravity, so that the liquid expands on the guide surface. Through the expansion of the liquid jet, the cleaning element can be wetted uniformly over the entire longitudinal extension of the cleaning element. The cleaning element is preferably movable relative to the guide surface during the wetting process, that is, if the non-planar cleaning element can move back and forth with respect to the guide surface, the cleaning element configured as a cleaning roller is rotated about the rotation axis Spin. Relative release through cleaning elements The relative displacement or rotation of the guide surface of the liquid discharge film can evenly wet the entire surface of the cleaning element. In order to spread the liquid applied to the guide surface as wide as possible and thus to wet the widest area on the cleaning element, the liquid should preferably be applied almost perpendicularly to the guide surface. It is recommended to form an angle between 90 ° and 170 °, especially between 90 ° and 105 °, between the guide surface and the liquid discharge direction of the liquid nozzle. Practice has shown that an angle greater than 105 ° between the guide surface and the direction of liquid discharge will severely reduce the expansion width of the liquid jet.

According to the present invention, the guide surface simultaneously performs several tasks. Specifically, one is to expand the liquid ejected from the liquid nozzle, and the other is to guide the liquid fan surface flowing along the guide surface to the cleaning element. Overall, this allows the cleaning element to be fully, uniformly, but only slightly moistened, thereby reducing the overall amount of liquid needed to wet the cleaning element. Other functions of the guide surface will be described in detail below in conjunction with the dependent items.

The invention particularly suggests that the guide surface is also displaceable relative to the cleaning element. To this end, for example, the guide surface can be supported on the wet cleaning device in such a manner that it can be pivoted about a deflection axis. In this way, the guide surface can be moved away from or towards the cleaning element, so that it can be used, for example, in a wiping operation for wetting the cleaning element, for a wet cleaning device (not continuously wetting the cleaning element) and / or Choose between different positions of the regeneration operation for the purpose of cleaning the cleaning element.

The invention particularly proposes that the guide surface bears against the cleaning element with a contact surface. According to this technical solution, the guide surface contacts the cleaning element, wherein a contact surface is formed between the guide surface and the cleaning element. In this case, the liquid applied to the cleaning element cannot flow smoothly on the surface of the cleaning element, but is preferably accumulated in the area of the contact surface, thereby extending the action time of the liquid available to the material of the cleaning element. In addition, cleaning elements (e.g., fibers of a cleaning cover) are compressed on the contact surface to prevent liquid loss. If the cleaning element is a cleaning roller, a wedge-shaped storage is generated in the area of the contact surface. The accumulated volume is formed between the guide surface and the cleaning element like a groove along the longitudinal direction of the cleaning drum. When the cleaning roller rotates, this accumulated volume is distributed on the surface of the cleaning roller in the circumferential direction along the rotation direction of the cleaning roller. Through the expansion of the liquid jet on the guide surface, the entire longitudinal extension of the cleaning element can be achieved according to specific structural conditions. This point mainly depends on the distance from the liquid nozzle to the guide surface, the speed of the liquid discharged by the discharge nozzle, the direction of liquid discharge from the guide surface with respect to the liquid nozzle, the inclination angle with respect to the direction of gravity, and the surface characteristics of the guide surface.

The invention particularly proposes that the guide surface acts on the cleaning element with a pressing force of 5N to 10N. This pressing force can be obtained only by the gravity acting on the guide surface, that is, depending on the specific quality of the guide surface, or, as an alternative or supplement, by a pressing device acting on the guide surface It is obtained that the pressing device is, for example, an elastic element, and its resetting force presses the guide surface against the cleaning element. The pressing force applied when the guide surface is pressed against the cleaning element is used to make the guide surface as close to the cleaning element as possible in a fluid-tight manner, so that the liquid accumulated in the accumulation volume between the guide surface and the cleaning element It cannot flow smoothly on the surface of the cleaning element, but when the cleaning element moves relative to the guide surface, that is, when it moves forward or backward, or rotates, it sweeps across the surface of the cleaning element in a targeted manner.

The invention particularly recommends that the contact surface has a height of 1 cm to 4 cm, particularly preferably about 2 cm, in the incident plane formed by the liquid's flow path. Wherein, the contact surface forms a region, and the guide surface is pressed against the cleaning element in this region. The size of the contact surface depends in particular on the possible curvature of the guide surface and / or the possible curvature of the cleaning element. It has been shown that in the case of a cleaning element designed as a cleaning cylinder with a diameter of 4.5 cm, it is advantageous if the contact surface has an extension of 2 cm, for example. This extension of the contact surface helps to achieve an optimal seal of the accumulated volume. In addition, the controlled compression of the cleaning cover through the cleaning element in the area of the contact surface prevents liquid damage Missed. Furthermore, the contact surface helps the liquid to reach an optimal period of action on the cleaning element.

The invention further proposes that the wetting device has a plurality of liquid nozzles arranged parallel to the longitudinal extension of the cleaning element. If the cleaning element is, for example, a cleaning drum, the liquid nozzles are arranged parallel to the drum axis. Thereby, a liquid can be applied to the entire cleaning element, that is, to the entire surface thereof. This is achieved on the one hand through the distribution of several liquid nozzles, and on the other hand through the displacement or rotation of the cleaning element relative to the guide surface. The number of liquid nozzles extending along the entire longitudinal direction of the cleaning element to wet the cleaning element depends on the spread of the fluid jet in the area of the contact surface. For example, the liquid nozzles can be arranged at a distance of several centimeters, for example, at a distance of between 3 cm and 6 cm.

The invention proposes that the liquid nozzle has a discharge hole with a diameter of 0.1 mm to 2 mm, especially about 1 mm. The liquid nozzle is, for example, a tubular nozzle. Through a small aperture, a fine liquid jet with a sufficiently high speed can be obtained in order to overcome the distance between the discharge hole of the liquid nozzle and the midpoint of the shot on the guide surface.

According to a preferred embodiment, the liquid nozzle is provided on the guide surface. Therefore, the liquid nozzle is not fixed on the wet cleaning device alone, but is directly provided on the guide surface, so that the liquid loss caused by the distance between the discharge hole of the liquid nozzle and the guide surface can be avoided or at least reduced. In addition to the liquid nozzle, one or more deflection elements may be provided on the guide surface. The deflection elements distribute and / or guide the liquid flowing along the guide surface. The deflection element can be configured, for example, as a protrusion provided on the guide surface or as a groove formed in the guide surface.

The invention further proposes that when the guide surface contacts the cleaning element, it has an angle of about 30 ° to 60 °, especially 45 °, relative to the horizontal plane. The above-mentioned oblique positioning of the guide surface with respect to the horizontal plane enables liquid to flow to the cleaning element under the action of gravity. The oblique position is relative to the liquid discharge direction of the liquid nozzle, and this oblique position helps to achieve the expansion proposed by the present invention.

The invention proposes that the guide surface is concavely curved on the side directed to the cleaning element, and / or has a surface coating, and / or has a surface structure. According to this, in addition to constructing the guide surface as the simplest smooth plane, the guide surface may also have a curved portion, specifically, a curved portion with a recess on the side thereof abutting on the cleaning element. As a result, the contact surface between the guide surface and the cleaning element is increased, and in particular, the period of time during which liquid can enter the cleaning element is also extended. In addition, the guide surface may also have a surface coating, for example, a coating having a hydrophilic or hydrophobic effect. This coating changes the flow characteristics of the liquid on the guide surface. Specifically, for example, it mainly changes the liquid on the guide surface. Velocity when the surface is flowing downward. In addition, a surface structure may be provided, for example, the surface may be structured with a conductive property by a structure such as a groove, a groove, or a bump.

In addition to the wet cleaning apparatus of the present invention, a method for operating a wet cleaning apparatus is also proposed, in which a liquid is applied to a cleaning element by a wetting device, and the liquid is accelerated from a liquid nozzle of the wetting device. It is discharged onto a guide surface, expands when hitting the guide surface, and reaches the cleaning element along the guide surface under the action of gravity, wherein it is between 90 ° and 170 °, especially between 90 ° The angle between and 105 ° applies liquid to the guide surface. In addition, the features described above in connection with wet cleaning equipment are also applicable to the operation method of this wet cleaning equipment.

The invention finally proposes that the cleaning element is a cleaning roller, during the application of the liquid, particularly at a rotation speed between 100 revolutions per minute and 600 revolutions per minute, particularly preferably between 200 revolutions per minute and 450 revolutions per minute. The rotation speed rotates around the rotation axis. The rotation speed of the cleaning drum should be mainly designed based on the diameter of the cleaning drum and the amount of liquid to be applied to the cleaning drum. In particular, by the amount of liquid applied to the cleaning roller, The effected period of time should be at least equal to the period of time that the cleaning roller rotates one revolution. The rotation speed proposed by the present invention, which is preferably 200 to 450 revolutions per minute, is particularly suitable for a rotating drum having a diameter of 4.5 cm.

Within the scope of the present invention, wet cleaning equipment refers in principle to all equipment with wet cleaning as its sole or main function. Such equipment includes handheld and automatic wet cleaning equipment, and particularly cleaning robots. In addition, the combined dry and wet cleaning equipment is also referred to as the wet cleaning equipment of the present invention. In addition, in addition to ordinary floor cleaning equipment used for floors, it also refers to wet cleaning equipment used to clean the area above the floor, such as window cleaning equipment.

1‧‧‧ Wet cleaning equipment

2‧‧‧ Cleaning Elements

3‧‧‧rotation axis

4‧‧‧ Wetting device

5‧‧‧ liquid nozzle

6‧‧‧ Guide surface

7‧‧‧ contact surface

8‧‧‧ discharge hole

9‧‧‧ basic equipment

10‧‧‧ Add-ons

11‧‧‧ handle

12‧‧‧handle

13‧‧‧ Filling tube

14‧‧‧deflection axis

15‧‧‧Cleaning Cover

16‧‧‧ Accumulated volume

17‧‧‧ fiber

α‧‧‧ (guide surface relative to the direction of liquid discharge) angle

β‧‧‧ (Guiding plane relative to horizontal plane) angle

r‧‧‧rotation direction

x‧‧‧ discharge direction

Fig. 1 is a schematic diagram of a wet cleaning device of the present invention; Fig. 2 is a schematic diagram of a partition of a wet cleaning device having a cleaning element and a wetting device; Fig. 3 is an enlarged view of a cleaning element having a wetting device; FIG. 2 is a top view of the cleaning element and the wetting device; FIG. 5 is a side perspective perspective view of a side of the guide surface facing the cleaning element.

The present invention is described in detail below with reference to the examples. FIG. 1 shows a wet cleaning device 1, which is here configured as a handheld wet cleaning device 1 with a basic device 9 and an attachment 10. The attachment 10 is detachably held on the base device 9. In addition, the basic device 9 has a handle 11, for example, a telescopic design is adopted here, so that a user of the wet cleaning device 1 can adjust the length of the handle 11 according to his height. A handle 12 is further provided on the handle 11, and the user can use the handle to operate during the normal wiping operation. The wet cleaning device 1 is moved on the surface to be cleaned. During the wiping operation, the user usually manipulates the wet cleaning device 1 to move on the surface to be cleaned in the opposite direction of movement. During this process, the user alternately pushes and pulls the wet cleaning device 1 away.

The attachment 10 has a housing in which the cleaning element 2 is held, and the cleaning element is here a cleaning roller. The casing is provided with a filling pipe 13 through which liquid can be filled into a liquid tank (not shown). The liquid stored in the tank is used to wet the cleaning element 2 from the outside.

The cleaning element 2 is supported inside the housing of the attachment 10 in a rotatable manner about a rotation axis 3. During the wiping operation, the cleaning element 2 is rotated around the rotation shaft 3 at a rotation speed of 350 revolutions per minute, for example, so that the peripheral surface of the cleaning element 2 continuously rolls on the surface to be cleaned. The cleaning member 2 is usually wrapped with a cleaning cover 15, and a sponge body that additionally functions as a liquid storage is sandwiched between the two as appropriate. The cleaning cover 15 is, for example, a textile cleaning cloth, and a plurality of fibers 17 can contain a liquid between them. The outer diameter of the cleaning element 2 including the fibers 17 is 46 mm, for example.

During the wiping operation, dirt is continuously accumulated on the cleaning element 2, that is, on the cleaning cover 15. Therefore, it may be necessary to regenerate the cleaning element 2 after working for a certain period of time, wherein during the regeneration operation, dirt and liquid with dirt are removed from the cleaning element 2.

FIG. 2 shows a section of the attachment 10 in which the cleaning element 2 is held in such a way that it can be rotated about the rotation axis 3. The cleaning element 2 is surrounded by a cleaning cover 15, which has a large number of fibers 17. The cleaning element 2 corresponds to a wetting device 4 having a total of four liquid nozzles 5 (see FIG. 4) and a guide surface 6. The guide surface 6 is supported on the attachment 10 in such a manner that it can be deflected about the deflection axis 14 and is abutted against the cleaning cover 15 under the influence of gravity in FIG. 2. The plurality of fibers 17 of the cleaning cover 15 are compressed by the gravity acting on the guide surface 6. In this region, there is a contact surface 7 between the guide surface 6 and the cleaning element 2, which in this case has an extension of approximately 2 cm in the circumferential direction of the cleaning element 2. On the one hand, the contact surface 7 extends along the axial direction of the rotating shaft 3 and covers the entire longitudinal extension of the cleaning element 2; on the other hand, as shown in the figure, it extends along the circumferential direction of the cleaning element 2. The liquid nozzles 5 are arranged side by side along the axial direction of the rotation axis 3 (see FIG. 4), and each has a discharge hole 8 with a diameter of about 1 mm. The liquid nozzle 5 corresponds to a pump (not shown) that conveys liquid from a liquid tank of the wet cleaning apparatus 1. The period of time during which the liquid is released is, for example, a period of time during which the cleaning element 2 rotates two to three revolutions. The amount of liquid released is 5 for example 3 ml per liquid nozzle. The distance between the discharge hole 8 of the liquid nozzle 5 and the guide surface 6 in the liquid discharge direction x is about 10 mm. The liquid system hits the guide surface 6 at a speed of about 11 m per second, and flows downward on the guide surface 6 by a distance of, for example, 25 mm until it reaches the surface of the cleaning element 2. In the meantime, the liquid extends, for example, to a width of 50 mm to 60 mm. For clarity, the figures are not drawn to scale. In the area in front of the contact surface 7, liquids converge to form an accumulation volume 16. The cleaning element 2 rotates counterclockwise in the direction of rotation r, wherein the liquid system contained in the accumulation volume 16 is dispensed onto and into the cleaning cover 15 through the guide surface 6, and is particularly pressed into the cleaning cover. Between the many fibers 17 of the object 15.

FIG. 3 shows an enlarged schematic view of another cleaning element 2 with a wetting device 4. Here, the cleaning element 2 is still configured as a cleaning drum that rotates around the rotation axis 3, which rotates counterclockwise around the rotation axis 3. The cleaning cover 15 has a fine fiber structure. The wetting device 4 here comprises, for example, two liquid nozzles 5 (see the perspective perspective view of FIG. 5) and a guide surface 6, which can be deflected about the deflection axis 14 relative to the cleaning element 2. On the side of the guide surface 6 facing the cleaning element 2, An angle α is formed between the liquid discharge direction x of the mouth 5 and the guide surface 6, which is about 105 °. In addition, the guide surface 6 has an inclination of 75 ° with respect to the horizontal plane. The liquid discharged from the discharge hole 8 of the liquid nozzle 5 hits the guide surface 6, and a substantially circular liquid spot is first formed on the guide surface 6. Then, the liquid spot expands under the influence of gravity when the liquid moves downward in the direction of the cleaning element 2, so that the formed liquid fan surface has a liquid spot in the axial direction of the cleaning element 2 than the liquid spot originally applied to the guide surface 6. For large width. The liquid flowing down on the guide surface 6 enters the area of the contact surface 7 between the guide surface 6 and the cleaning element 2, where it reaches the accumulation volume 16 which has been formed between the guide surface 6 and the cleaning element 2. . The guide surface 6 is solely based on the gravity acting on the guide surface 6 and is pressed against the cleaning cover 15 of the cleaning element 2 with a pressing force of 8 N here. As a result, the fibers 17 of the cleaning cover 15 are compressed, and the liquid can no longer pass between the guide surface 6 and the cleaning element 2. The cleaning element 2 rotates counterclockwise around the rotation axis 3, wherein the cleaning cover 15 always sweeps the accumulated volume 16 of the liquid in the circumferential direction in different sections. The liquid is thus distributed on the peripheral surface of the cleaning cover 15 and among the fibers 17 of the cleaning cover 15, and in particular, is distributed along the rotation axis 3 in the entire longitudinal direction of the cleaning cover 15. Extend on. The accumulation volume 16 forms the amount of liquid residing on the cleaning cover 15. This liquid amount continuously releases the liquid component volume to the cleaning cover 15, and a new liquid component volume is sucked from the guide surface 6. Based on the size of the accumulation volume 16 and the rotation speed of the cleaning element 2, a period of time is generated. During this time, the accumulation volume 16 resides on the partition of the peripheral surface of the cleaning element 2, and the cleaning cover can be wetted there. 15. The dimensions given in conjunction with the embodiment shown in FIG. 2 can also be exemplarily applied to the embodiment shown in FIG. 3.

FIG. 4 shows a top view of the partition 10 with the cleaning element 2 and the wetting device 4 as shown in FIG. 2. The wetting device 4 has four Spacing arrangement of liquid nozzles 5.

FIG. 5 shows a perspective perspective view of the side of the guide surface 6 facing the cleaning element 2. The wetting device 4 basically corresponds to the structure shown in FIG. 3. The liquid spots on the guide surface 6 can be seen in the drawing. These liquid spots are formed by the liquid discharged from the discharge hole 8 of the liquid nozzle 5 and are guided along the guide surface 6 toward the cleaning element under the action of gravity. The direction of 2 extends so as to extend along the entire longitudinal direction of the cleaning element 2, that is, in the direction of the rotation axis 3, to wet the cleaning cover 15 of the cleaning element 2.

2‧‧‧ Cleaning Elements

3‧‧‧rotation axis

4‧‧‧ Wetting device

5‧‧‧ liquid nozzle

6‧‧‧ Guide surface

7‧‧‧ contact surface

8‧‧‧ discharge hole

10‧‧‧ Add-ons

13‧‧‧ Filling tube

14‧‧‧deflection axis

15‧‧‧Cleaning Cover

16‧‧‧ Accumulated volume

17‧‧‧ fiber

r‧‧‧rotation direction

x‧‧‧ discharge direction

Claims (10)

A wet-type cleaning device, particularly a wet-wiping device, having a cleaning element (2), in particular a cleaning roller rotatable about a rotation axis (3), and a wetting device for applying liquid to the cleaning element (2) ( 4), characterized in that the wetting device (4) has a guide surface (6) for liquid, which is provided on a liquid flow path between a liquid nozzle (5) and the cleaning element (2) And is particularly displaceable relative to the cleaning element (2), wherein the guide surface (6) is between 90 ° and 170 ° with respect to the liquid discharge direction (x) of the liquid nozzle (5) Angle (α) between 90 ° and 105 °, so that the liquid expelled from the liquid nozzle (5) onto the guide surface (6) hits the guide surface ( 6) when expanding, and reach the cleaning element (2) along the guide surface (6) under the action of gravity. The wet-type cleaning device as claimed in claim 1, wherein the guide surface (6) abuts the cleaning element (2) with a contact surface (7), and in particular, the pressing force acts on the cleaning with a pressing force of 5N to 10N. The element (2), wherein the contact surface (7) has a height of 1 cm to 4 cm, particularly preferably about 2 cm in an incident plane formed by its flow path. For example, the wet cleaning device of claim 1 or 2, wherein the pressing force exerted by the guide surface (6) on the cleaning element (2) is consistent with the gravity acting on the guide surface (6). , And / or depends on the elastic force of the elastic element that urges the guide surface (6) toward the cleaning element (2). The wet cleaning device according to any one of the preceding claims, wherein the wetting device (4) has a plurality of liquid nozzles (5) arranged parallel to the longitudinal extension of the cleaning element (2). The wet-type cleaning apparatus according to any one of the preceding claims, wherein the liquid nozzle (5) has a discharge hole (8) having a hole diameter of 0.1 mm to 2 mm, particularly about 1 mm. The wet cleaning apparatus according to any one of the preceding claims, wherein the liquid nozzle (5) It is set on the guide surface (6). The wet cleaning device according to any one of the preceding claims, wherein when the guide surface (6) contacts the cleaning element (2), it has an angle of about 30 ° to 90 ° with respect to the horizontal plane, in particular 45 ° ( β). The wet cleaning device according to any one of the preceding claims, wherein the guide surface (6) is concavely curved on a side directed to the cleaning element (2), and / or has a surface coating, and / or Has a surface structure. A method for operating a wet cleaning device, in particular a method for operating a wet cleaning device (1) according to any one of the preceding claims, wherein a liquid is applied to the cleaning element (2) by a wetting device (4), which It is characterized in that the liquid is accelerated to be discharged from a liquid nozzle (5) of the wetting device (4) onto a guide surface (6), expands when hitting the guide surface (6), and acts on gravity The lower edge of the guide surface (6) reaches the cleaning element (2), wherein the guide is directed at an angle (α) between 90 ° and 170 °, especially between 90 ° and 105 °. The surface (6) applies a liquid. The method according to claim 9, wherein the cleaning element (2) is a cleaning roller, during the application of the liquid, particularly at a rotation speed between 100 rpm and 600 rpm, particularly preferably at 200 rpm The rotation speed between the minute and 450 rpm rotates around the rotation axis (3).