KR102700204B1 - Wet cleaning device - Google Patents

Abstract

A wet cleaning device (WCD) comprises a mopping unit (MU) for wet cleaning a surface, and a device (ST) for increasing the pressure of the mopping unit against the surface by suction. The device (ST) comprises a hose at one side of the mopping unit (MU), the hose having an opening for applying suction to the surface. The hose may be present at opposite sides of the mopping unit (MU). Alternatively, the hose may be present around the mopping unit (MU). Preferably, the suction of the device is controllable. Advantageously, the suction is controllable depending on the detection of a stain, the speed of the wet cleaning device (WCD), and/or the type of surface. When the wet cleaning device (WCD) is formed by a mopping robot vacuum cleaner, the suction for the device (ST) is advantageously part of the suction generated for vacuum cleaning.

Description

Wet cleaning device

The present invention relates to a wet cleaning device.

Tough floor cleaning is traditionally done by first vacuuming the floor and then mopping the floor. Vacuuming removes coarse dirt, while mopping removes stains. In recent years, more and more devices have come onto the market that feature vacuuming and mopping at the same time. Robot vacuum cleaners also offer a solution for vacuuming and mopping the floor. For this purpose, a water tank with a mop is attached to the (vacuuming) robot.

U.S. Patent Application Publication No. 2014033468 discloses a floor tool in the sense that it is a dual-function vacuum cleaning device. First, the floor tool provides a suction cleaning function; second, the floor tool has the ability to support a cleaning element, preferably in the form of a wiping sheet, for vacuuming a floor surface and wiping the floor surface at the same time. The suction nozzle is configured to float relative to a connecting neck of the floor tool, which provides several advantages. First, the downward force applied to the user through the neck is directly transmitted to the supporting member and not to the suction nozzle, which improves the cleaning performance of the wiping sheet supported on the supporting member. Second, since the suction nozzle is subjected to a very small downward force, it can be gently pushed across the floor surface, which is beneficial to the pick-up performance of the suction nozzle.

U.S. Patent Application Publication No. 2017367552 discloses a self-moving floor treatment device including a machine body base and a water tank. A cleaning cloth is attached to the bottom of the water tank, and the water tank is connected to the bottom surface of the machine body base in a manner of floating up and down. By mounting the water tank on the machine body base in a floating manner so as to leave a predetermined gap therebetween, the water tank and the cleaning cloth can float up and down within a predetermined space range. Since the actual force acting on the floor is only the gravity of the water tank and the cleaning cloth itself and does not include the gravity of the machine, compared with conventional products, the frictional force between the cleaning cloth and the floor is reduced, the phenomenon of the machine slipping on the floor with water can be effectively avoided, the floor cleaning efficiency is improved, and the obstacle crossing ability of the machine with the water tank is improved.

The object of the present invention is in particular to provide an improved wet cleaning device. The invention is defined by the independent claims. Advantageous embodiments are defined in the dependent claims.

One aspect of the present invention comprises a mopping unit for wet cleaning a surface, and a device for increasing the pressure of the mopping unit against the surface by suction. The device comprises a hose on one side of the mopping unit, the hose having an opening for applying suction to the surface. The hose may be present on opposite sides of the mopping unit. Alternatively, the hose may be present around the mopping unit. Preferably, the suction power of the device is controllable. Advantageously, the suction power is controllable depending on the detection of a stain, the speed of the wet cleaning device, and/or the type of surface. When the wet cleaning device is formed by a mopping robot vacuum cleaner, the suction for the device is advantageously part of the suction generated for vacuum cleaning.

The present invention is based on the recognition that wet cleaning devices, such as robot vacuum cleaners, are preferably not very heavy so that a user can easily pick up the wet cleaning device. In order to mop a surface (e.g., a floor), some pressure on the surface is often required to remove heavy stains. Here, a contradiction is encountered. The wet cleaning device needs to be light in weight so that it can be easily lifted, but on the other hand, the wet cleaning device needs to provide sufficient pressure on the floor to enable the wet cleaning device to properly mop the surface. To overcome this contradiction, it is necessary to provide a way to apply force to the floor without making the wet cleaning device heavier.

One aspect of the present invention will be to enable a wet cleaning device to provide increased pressure on the ground during mopping while maintaining a lightweight design. Embodiments of the present invention provide an under-pressure region around a mopping unit to anchor the mopping unit to the ground. In a robotic vacuum cleaner embodiment, the under-pressure may advantageously be created by directing a portion of the airflow of the vacuum cleaner through a tubing system around the mop.

These and other aspects of the present invention will be apparent from and elucidated with reference to the embodiments described hereinafter.

FIG. 1 is a bottom view of one embodiment of a wet cleaning device according to the present invention.
Figure 2 is a drawing showing a cross-section of the embodiment of Figure 1.

Figures 1 and 2 relate to a wet cleaning device (WCD) formed by a mopping robot cleaner. As is typical, the mopping robot cleaner has wheels (W), a nozzle (N) having an optional rotating brush (B), and a mopping unit (MU). The mopping unit (MU) has a liquid tank (not shown) and a (replaceable) cleaning cloth. According to the present invention, a suction tool (ST) is provided on one side of the mopping unit (MU). In the illustrated embodiment, the suction tool (ST) is formed by a hose having a plurality of openings around the mopping unit (MU). Alternatively, the hose may have slit-shaped openings. The hose may be made of rubber or some suitable plastic or other suitable material. The hose may be bonded to the mopping unit (MU).

As illustrated in FIG. 2, dirty air from a nozzle (N) is guided to a dirt separation and collection unit (DC), as is typical for a vacuum cleaner, through which an air flow is generated by a fan (F). According to one embodiment of the present invention, part of the air flow generated by the fan (F) is used to generate suction for a suction tool (ST). A valve (V) is present to control how much air flow is available for the suction tool (ST). The valve (V) may be formed by a clamp around a hose: if the hose is compressed by the clamp, less suction is available to the suction tool (ST). Advantageously, the amount of suction available to the suction tool (ST) depends on the detection of a stain (presence of a stain => greater suction), the speed of the wet cleaning device (WCD) (too low speed => reduced suction), and/or the type of surface. To control the valve, a processor (which is present in the robot vacuum cleaner anyway) receives data (e.g. from a camera (not shown)) and has software which can determine the presence of stains and the type of surface from the camera image. This software can include artificial intelligence based on a trained neural network. The wheel speed can be derived, for example, from the amount of current drawn by the motor that rotates the wheels (W): if the current is relatively high, the motor should work powerfully, so that it is reasonable to reduce the suction for the suction tool and thus reduce friction.

It should be noted that the above-mentioned embodiments illustrate rather than limit the present invention, and that those skilled in the art will be able to design many alternative embodiments without departing from the scope of the appended claims. In the above examples, a rectangular robot vacuum cleaner is depicted having a rectangular mopping unit (MU). Obviously, the wet cleaning device may have a different shape (e.g., circular), and the same is mentioned for the mopping unit (MU) which may have a shape as illustrated in, for example, U.S. Patent Application Publication No. 2017367552. In the depicted embodiment, the mopping unit (MU) is surrounded by a suction tool (ST), however, in other embodiments, the suction tool (ST) is only present on one side or the opposite side of the mopping unit (MU). The suction tool (ST) need not be along one side, i.e., the suction tool need not have an elongated shape, as long as the suction tool causes the mopping unit (MU) to exert increased pressure on the surface. The wet cleaning device of the present invention may also be arranged to clean (vertical) surfaces such as windows or walls. The wet cleaning device of the present invention need not have a vacuum cleaner function. And, if the wet cleaning device has a vacuum cleaner function, it may or may not use a vacuum cleaner fan (F) to generate suction to increase the pressure of the mopping unit against the surface; a separate low-power fan may be used for this purpose, which may have the advantage that better control of the mopping pressure may be achieved independently of the vacuum cleaning operation. The wet cleaning device with a vacuum cleaner function may have the following different operating modes: (1) vacuum cleaning only, (2) wet cleaning only, and (3) both vacuum cleaning and wet cleaning. In the second mode, the use of a separate suction unit to generate the underpressure may have the advantage that less energy is consumed. In the claims, any reference numeral indicated in parentheses shall not be construed as limiting the claim. The word "comprising" does not exclude the presence of elements or steps other than those listed in a claim. The singular form "a" or "an" preceding an element does not exclude the presence of plural such elements. The invention may be implemented by hardware comprising several distinct elements. In a device claim enumerating several means, several of these means may be implemented by one and the same item of hardware. Measures recited in different dependent claims may advantageously be used in combination.

Claims (8)

As a wet cleaning device (WCD),
A mopping unit (MU) for wet cleaning the surface; and
Including a device (ST) for increasing the pressure of the mop unit against the surface by suction,
A wet cleaning device (WCD), wherein the above equipment (ST) includes a hose at one side of the mopping unit (MU), the hose having an opening for applying suction to the surface. A wet cleaning device (WCD) in the first aspect, wherein the hose is present on opposite sides of the mopping unit (MU). In the first paragraph, a wet cleaning device (WCD) wherein the hose is present around the mopping unit (MU). A wet cleaning device (WCD) according to any one of claims 1 to 3, wherein the suction power of the equipment (ST) is controllable. A wet cleaning device (WCD) in accordance with claim 4, wherein the suction power is controllable according to detection of stains. In the fourth paragraph, a wet cleaning device (WCD) wherein the suction power is controllable according to the speed of the wet cleaning device. A wet cleaning device (WCD) in accordance with claim 4, wherein the suction power is controllable according to the type of the surface. A wet cleaning device (WCD) according to any one of claims 1 to 3, wherein the wet cleaning device is formed by a mopping robot vacuum cleaner, and the suction for the device is a part of the suction generated for vacuum cleaning.

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