Scrubber-drier

Abstract

A scrubber-drier for cleaning surfaces, the scrubber-drier comprising: - at least one cleaning tool; - a first brushless electrical motor, for transporting a volume of air; - a second brushless electrical motor, for driving at least one of the at least one cleaning tools; and - an electrical circuit comprising integrated control for the first brushless motor and the second brushless motor, the electrical circuit being physically separated from each of the first and the second brushless motor, the electrical circuit being in wired or wire-less communication with the first brushless motor and the second brushless motor.

Description

[0001] Title: scrubber-drier

[0002] BACKGROUND

[0003] The present disclosure relates to a scrubber-drier. In particular, the present disclosure relates to a scrubber-drier that has a guide part and a handle with which the scrubber-drier is guided by a user, and having cleaning tools which propel the device forwards. Such a scrubber-drier typically comprises a guide part and a handle, as well as cleaning tools in contact with the surface to be cleaned, a clean water tank, a dirty water tank and a squeegee. In typical use, water is sprayed on a surface to be cleaned, along with a cleaning solution. The surface to be cleaned is scrubbed by the cleaning tools, to clean the surface. The water, as well as the dirt scrubbed off the surface by the cleaning tools, is then sucked up by the squeegee and transported towards the dirty water tank. Hence, the scrubber-drier carries the water with which the surface is to be cleaned, as well as the water which is used to clean the surface; the cleaned surface is left behind substantially dry and one can walk behind the device. It is noted that although scrubber-drier may be designed for cleaning surfaces with water, using a wet cleaning method, they may alternatively be operated as cleaning devices using air suction only, more akin to traditional vacuum machines.

[0004] Examples of such scrubber-driers are described e.g. in patent application WO 2022 / 039591 A2 in the name of the same applicant, and in WO 2011023169 A2, both incorporated by reference in the present application.

[0005] Presently-known scrubber-driers typically have one or two electrical motors for driving the cleaning tools of the scrubber-drier as well as an electrical turbine motor for transporting a volume of air. Such electrical motors could be of the type “carbon brushes” or of the type “direct current brushless motor”, the latter also known as BLDC. In case a BLDC motor is used, it should contain its own control hard- and software, in the form of a printed circuit board integrated with the motor. These electrical motors are typically buy-in parts for the manufacturer of the scrubber-drier. Of course, it is critical that in operation of the scrubber-drier, in particular when using liquids such as water to clean the surface to be cleaned, the electrical motors and the control hardware remains dry. As such, these motors are relatively expensive components and these motors themselves do not by default have their own liquid-proof sealing specification which means that, to render them useful for a scrubber-drier, the motors as well as the control hardware must be protected by a liquid-proof sealing enclosure.

[0006] It has been an object of the present applicant to, on the one hand, simplify the design of a scrubber-drier, so that less expensive parts may be used to obtain an equally-good, or better, scrubber-drier. On the other hand, it has been an objective of the present applicant to design a scrubber-drier that is more reliable in terms of operational conditions and boundaries, where the handling of wetted air poses less problems and where failure of components occurs at a lower frequency.

[0007] SUMMARY OF THE DISCLOSURE

[0008] Accordingly, the present disclosure relates to a scrubber-drier for cleaning surfaces, the scrubber-drier comprising: at least one cleaning tool; a first brushless electrical motor, for transporting a volume of air; a second brushless electrical motor, for driving at least one of the at least one cleaning tools; and an electrical circuit comprising integrated control for the first brushless motor and the second brushless motor, the electrical circuit being physically separated from each of the first and the second brushless motor, the electrical circuit being in wired or wire-less communication with the first brushless motor and the second brushless motor.

[0009] One of the inventive concepts underlying the present disclosure is that, by physically separating the electrical circuits which control the first and second brushless motors from the brushless motors themselves, one the one hand only one electrical circuit is required for all control logic, which may save cost and which may yield to integration advantages that will be explained in more detail in the below. On the other hand, the motors themselves may become simpler in design, omitting the control circuit and omitting the requirement that the control circuit must be protected from becoming wet at all times. Especially for scrubber-driers, that are designed to work with water and wet air, the latter imposes strict sealing requirements, that must be inspected from time to time, leading to all associated disadvantages. These are, then, omitted in the solution as presented herewith.

[0010] Advantageously, the electrical circuit may be placed at a position which is less prone to becoming wet, and potentially may be integrated with a further electrical circuit, that was already part of the scrubber-drier and that was already designed in a fluid-tight manner, as will be detailed in the below.

[0011] Advantageously, because the control circuit is now separated from the brushless motors themselves, these brushless motors are less sensitive to liquids.

[0012] As such, whereas presently known scrubber-drier all have motors that each comprise their own dedicated electrical circuit, according to the present disclosure these dedicated electrical circuits may be removed from the different motors and be integrated at a position that is physically positioned away from the motors, to be connected to the motors with a wired or a wire-less connection.

[0013] According to the present disclosure, the scrubber-drier is arranged for cleaning surfaces. For example, the surface to be cleaned can be a floor, that may be inclined at a positive or negative inclination angle, or that may be arranged substantially horizontally. In other examples, the surface to be cleaned may be a wall or a ceiling, which may respectively be arranged substantially vertically or horizontally.

[0014] According to the present disclosure, the scrubber-drier comprises at least one cleaning tool. In particular, the scrubber-drier may comprise a pair of cleaning tools, i.e. two cleaning tools, or possibly more than that. In particular, the cleaning tools may be inclined with respect to the horizontal, so that they propel themselves forward. More in particular, the inclination angle of the cleaning tools may be variable, e.g. depending on the inclination angle of the guide part. All of this is described in previous patent applications of the present applicant.

[0015] According to the present disclosure, the scrubber-drier comprises a first brushless electrical motor. The first electrical motor may in particular comprise a stator and a rotor, the rotor being rotated by applying electrical energy to the electromagnets of the stator. In return, the rotor starts spinning. A fan may be mounted on the rotor, the fan co-rotating with the rotor and ensuring the transportation of air. In particular, the air may be wetted, although the handling of dry air is usually also possible. To operate the brushless electrical motor, control software and / or hardware is needed. This control software and / or hardware is arranged on the integrated electrical circuit.

[0016] According to the present disclosure, the scrubber-drier comprises at least a second brushless electrical motor for driving a cleaning tool. When there is only one cleaning tool to be driven, there may obviously be only one driving motor. When there are two or more cleaning tools to be driven, there may be a single motor driving all of the tools, a motor may be associated with each cleaning tool, or, especially when there would be more than two cleaning tools, the number of motors may be lower than the number of cleaning tools but higher than one - e.g. four cleaning tools and two motors.

[0017] For controlling the motors, according to the disclosure an integrated control is provided. The integrated control contains substantially all control, e.g. in terms of hardware and software, that is needed to control the at least two different motors of the cleaning device. In particular, the integrated control is arranged on a single electrical circuit, that is positioned at a location physically away from both motors.

[0018] In an embodiment of the present disclosure, the first brushless electrical motor is of the through-flow type and is configured for transporting both wet and dry air, a rotor of the brushless electrical motor being sealed in a fluid-tight manner by a housing, the rotor arranged in heat-exchanging communication with the housing, the air flow transported by the brushless electrical motor being in contact with the housing for cooling the housing. A motor of the through-flow type has a higher efficiency than a motor of the by-pass type, which is more conventional for working with wet air. It is the housing around the stator which prevents the wet air from deteriorating the electrical motor, while the heat-exchanging communication between the stator and the housing allows the stator to be cooled nonetheless. In one embodiment, the stator and housing may be in physical contact with each other, so that the heat exchanging contact may be defined by a convective heat exchange. In another embodiment, a heat exchange medium, e.g. air, may be arranged in between the stator and the housing, so that the heat exchanging contact may be defined by a radiative heat exchange. A liquid-tight rotary seal may be positioned in between the stator and the housing, to allow the stator to rotate despite the presence of the housing and to maintain a fluid-tight seal around the stator. In an embodiment of the present disclosure, the second brushless electrical motor comprises a gearbox, e.g. a planetary gearbox. This allows to obtain a higher efficiency, especially when the tools are to be driven at a relatively low range of rpm’s. In an embodiment of the present disclosure, at least one of the first and the second brushless electrical motors is powered by a battery that is releasably coupled to the scrubber-drier. The brushless electrical motors need electrical power to operate. This power can come, in embodiments, from a socket and a plug that is plugged into the socket, but this may lead to sub-optimal flexibility when the scrubber-drier is to be used for a long period of time and / or at locations that lack a socket. Hence, as an alternative, the motors may draw their electricity from a battery. Advantageously, the battery itself is releasably mounted on a battery station that is a part of the scrubberdrier. The battery itself can then be removed from the scrubber-drier to charge it at any desired location, while the scrubber-drier can be stored at a different location - or can be transported or can be used together with a second battery while the first battery is being charged.

[0019] Typically, the battery station comprises an electrical circuit. On the electrical circuit, e.g. control soft- and hardware is arranged that prevents unsafe operation of the battery in fail-modes of the battery itself. According to the present disclosure, the electrical circuit used for control of both motors may be integrated with the electrical circuit for controlling the battery.

[0020] In an embodiment of the present disclosure, the electrical circuit may be a printed circuit board, although other options for providing electrical circuit are well- known to one skilled in the art.

[0021] In an embodiment of the present disclosure, the integrated printed circuit board is configured for controlling the rotational speeds of the respective tools individually. This allows, for example, to rotate the tools with the same speed I rpm when the scrubberdrier is to move forwards in a straight line. It also allows to rotate the tools at a different speed I rpm when the scrubber-drier is to make a turn. In particular, when the scrubberdrier comprises two cleaning tools and is to make a left turn, the right tool may be rotated at a higher speed I rpm than the left tool, to allow the easy turning of the scrubber-drier. Likewise, when the scrubber-drier is to make a right turn, the left tool may be rotated at a higher speed / rpm. In other words, when the scrubber-drier is manipulated to effect a turn, the rotational speeds of the respective tools are preferably set at mutually different speeds by the integrated printed circuit board.

[0022] In an embodiment of the present disclosure, the scrubber-drier comprises at least two distinct motor: one for the transportation of air and one for driving the cleaning tool(s). Potentially, a single motor may fulfil both of these functions: drive the tool(s) as well as transporting air.

[0023] In an embodiment of the present disclosure, the scrubber-drier further comprises a third electrical motor, each of the second and third electrical motors configured for driving one of the cleaning tools. This may make it more easy to operate the different cleaning tools at a different speed I rpm.

[0024] In an embodiment of the present disclosure, the scrubber-drier further comprises a guide part having a handle, wherein in use the handle is held by a user which operates the scrubber-drier by walking behind the scrubber-drier. This, in contrast, to e.g. cleaning tools which operate fully automatically and / or cleaning tools on which one can sit.

[0025] In an embodiment of the present disclosure, the guide part comprises a gravity sensor that is arranged in communication with the integrated printed circuit board, wherein the rotational speeds of the tools are controlled based on measurements provided by the gravity sensor. This allows the scrubber-drier to automatically turn as soon as the guide part is manipulated by the user, without the user needing to exert any substantial forces on the scrubber-drier.

[0026] BRIEF DESCRIPTION OF THE DRAWINGS

[0027] These and other aspects of the present disclosure are further elucidated with reference to the attached figures. In these figures, like and same elements are indicated with the same reference numerals. In particular:

[0028] Fig. 1 schematically shows, in an isometric view from above, an embodiment of the scrubber-drier according to the present disclosure; and

[0029] Fig. 2 schematically shows, in an isometric view from above, the scrubberdrier of Figure 1 , wherein some of the parts are hidden so that other parts are shown more clearly. DETAILED DESCRIPTION OF THE DRAWINGS

[0030] Turning to Figure 1 initially, shown here is a scrubber-drier 100. The scrubberdrier 100 generally comprises a frame 15, on which two cleaning tools 1 , 2 are mounted as well as a hinge mechanism 16. Coupled to the hinge mechanism 16 is a guide part 10, to which a handle 11 is mounted at the end. The handle 11 comprises two bars at which a user can grab the scrubber-drier 100, and via which it can manipulate and operate the scrubber-drier 100. In particular, via the handle 11 the guide part 10 can be moved backwards and forwards as well as sidewards with respect to the neutral position thereof that is shown in Figure 1. When the guide part 10 is moved, and the scrubber-drier 100 is turned off, the frame 15 remains stationary. Movement of the guide part 10 with respect to the frame 15 is allowed by the hinge member 16, which preferably allows the guide part 10 to be rotated over more than 360 degrees about a vertical axis. Provided on the handle 11 is an operators screen 12 that may e.g. contain an informative screen displaying relevant information about the scrubber-drier 100 - such as running operational time, amount of battery left, potential warning signals, an on / off button, and other relevant information.

[0031] The scrubber-drier 100 may be used without water to clean a surface to be cleaned S. However, in the below only the operation with water is described.

[0032] Attached to the guide part 10 are clean water tank 13 and dirty water tank 14. The clean water tank 13 contains the water and, potentially, the cleaning solution with which a surface to be cleaned S is cleaned. In use, the water is sprayed in front of the tools 1 , 2 and / or injected in the tools 1 , 2 to scrub the surface by rotating the tools 1 , 2 using motors 4, 5 and clean the surface S. Electrical motors 4, 5 may comprise a planetary gearbox for efficient operation. Electrical motors 4, 5 are powered by battery 6 and, not visible, a further battery. These batteries are preferably releasably coupled to the scrubber-drier 100, so that when the battery is empty a different one can be put in place while the empty battery is charging, and operation of the scrubber-drier 100 may continue. Once the surface S is clean, and the water is dirty, the now-dirty water is sucked up by a squeegee 9 and stored in dirty water tank 14. The upwards transportation of the dirty water, along with air as a transportation medium, is carried out by a further electrical motor, that is not visible and generally indicated by reference numeral 3, that has a fan. In the shown scrubber-drier 100, all motors are brushless direct current motors, although that may not be true for scrubber-driers 100 in general.

[0033] The above described, very briefly, some general operating principles of the scrubber-drier of Figure 1. Turning now to Figure 2, only a few components of the scrubber-drier are shown therein. In particular, Figure 2 shows the batteries 6, 7 which power the various electrical motors 3, 4, 5. As mentioned in the above, there is one electrical motor 3 that transports (wet) air which has been sucked up by squeegee 9 from the surface to be cleaned to the dirty water tank. In particular, motor 3 is of the through-flow type and is configured for transporting both wet and dry air, a rotor of the motor 3 being sealed in a fluid-tight manner by a housing, the rotor arranged in heatexchanging communication with the housing, the air flow transported by the brushless electrical motor being in contact with the housing for cooling the housing. As such, the housing for the brushless motor is waterproof.

[0034] The other motors 4, 5 each drive a cleaning tool 1 , 2, although in other embodiments one motor may drive both cleaning tools 1 ,2. In yet other embodiments, the number of cleaning tools may differ from two, either being larger or smaller and / or there may be a single motor which fulfils both functions of driving the cleaning tools and transporting the (wet) air.

[0035] To operate the brushless direct current motors 3, 4, 5 one the one hand electrical power is required, and on the other hand control logic is required. Electrical power is provided by batteries 6, 7, which are mounted on the frame of the scrubber drier. Indeed, power supply cables are visible between the battery 6, 7 station and each of the motors 3, 4, 5 of the scrubber-drier.

[0036] Associated with the batteries is an electrical circuit 8, which contains control logic for the batteries 6, 7 - e.g. to prevent them from decharging below a certain minimum amount, to shut them off in case of an overcurrent being drawn, to detect other malfunctions and potentially more relatively standard control operations. As the scrubber-drier is designed to work with water that is scrubbed by the tools 1 , 2 and as the batteries are quite close to the tools 1 ,2, the electrical circuit 8 needs to be water-proof. Advantageously, the electrical circuit 8 associated with the batteries 6, 7 comprises not only the control hard- and software for controlling the batteries, but also functions as an integrated control for the motors 3, 4, 5 of the scrubber-drier. This results in a scrubber-drier that has the electrical circuit comprising the integrated control for the motors 3, 4, 5 and, optionally, also for the batteries 6, 7 physically separated from the motors 3, 4, 5. The electrical circuit 8, typically in the form of a printed circuit board, comprises hardware and software that together generate control signals for the purpose of operating the scrubber-drier and is constructed in a water-proof manner. The electrical circuit sends it’s control signals to the motors via e.g. a wire-less connection or via a wired connected e.g. integrated with the power supply cable or running parallel thereto.

[0037] A particular advantage of having de-centralized, integrated control over all motors 3, 4, 5 is that this not only makes the motors 3, 4, 5 themselves much more simple and cost-effective, it also allows all kinds of new control algorithms - in particular when the electric motors are brushless such as here. In particular, it become possible to have the integrated control set the rotational speeds of the respective cleaning tools 1 , 2 individually and independently. In particular, when the scrubber-dries is manipulated to effect a turn, the rotational speeds of the tools 1 , 2 may be set at mutually different speeds I rpm’s, the inner tool turning slower than the outer turn, to make the turn more easily and effectively, with less force needed by the operator of the scrubber-drier. For example, changing the relative rotational speeds of the tools 1 , 2 may be done after a gravity sensor integrated with the guide part has determined that the guide part is moved in the sidewards direction, to allow the scrubber-drier to turn in the direction in which the guide part is moved.

Claims

CLAIMS1. A scrubber-drier for cleaning surfaces, the scrubber-drier comprising: at least one cleaning tool; a first brushless electrical motor, for transporting a volume of air; a second brushless electrical motor, for driving at least one of the at least one cleaning tools; and an electrical circuit comprising integrated control for the first brushless motor and the second brushless motor, the electrical circuit being physically separated from each of the first and the second brushless motor, the electrical circuit being in wired or wire-less communication with the first brushless motor and the second brushless motor.

2. The scrubber-drier according to claim 1 , wherein the first brushless electrical motor is of the through-flow type and is configured for transporting both wet and dry air, a rotor of the brushless electrical motor being sealed in a fluid-tight manner by a housing, the rotor arranged in heat-exchanging communication with the housing, the air flow transported by the brushless electrical motor being in contact with the housing for cooling the housing.

3. The scrubber-drier according to claim 1 or 2, wherein the second brushless electrical motor comprises a gearbox, e.g. a planetary gearbox.

4. The scrubber-drier according to any one of the preceding claims, wherein at least one of the first and the second brushless electrical motors is powered by a battery that is releasably coupled to the scrubber-drier.

5. The scrubber-drier according to claim 4, wherein the integrated control on the electrical circuit further comprises control for the battery, and is associated with said battery.

6. The scrubber-drier according to any one of the preceding claims, wherein the electrical circuit is a printed circuit board.

7. The scrubber-drier according to any one of the preceding claims, wherein the integrated control is configured for controlling the rotational speeds of the respective tools individually.

8. The scrubber-drier according to any one of the preceding claims, wherein when the scrubber-drier is manipulated to effect a turn, the rotational speeds of the respective tools are set at mutually different speeds by the integrated electrical circuit.

9. The scrubber-drier according to any one of the preceding claims, wherein the first electrical motor and the second electrical motor are different motors.

10. The scrubber-drier according to any one of the preceding claims, further comprising a third electrical motor, each of the second and third electrical motors configured for driving one of the cleaning tools.

11. The scrubber-drier according to any one of the preceding claims, further comprising a guide part having a handle, wherein in use the handle is held by a user which operates the scrubber-drier by walking behind the scrubber-drier.

12. The scrubber-drier according to claim 11 , wherein the guide part comprises a gravity sensor that is arranged in communication with the integrated electrical circuit, wherein the rotational speeds of the tools are controlled based on measurements provided by the gravity sensor.

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