EP2043495A1

EP2043495A1 - A carpet cleaning device and a method for cleaning a carpet

Info

Publication number: EP2043495A1
Application number: EP07768990A
Authority: EP
Inventors: Håkan MIEFALK; Johann Zita; Andreas Pohl
Original assignee: Electrolux AB
Current assignee: Electrolux AB
Priority date: 2006-07-06
Filing date: 2007-07-06
Publication date: 2009-04-08
Also published as: WO2008004956A1; CN101484061A; SE530111C2; EP2043495A4; SE0601487L

Abstract

The invention relates to a carpet cleaning device being connectible to a vacuum cleaner provided with a hose and tube (7). The carpet cleaning device has an elongated air suction opening (11) facing the carpet to be cleaned, through which air can be drawn. A rotatably driven brush (10) is positioned in the air suction opening to accomplish agitation of the carpet surface. A valve means (12) is arranged for allowing switching of the air flow through the air suction opening or an alternative air inlet (3). The device also comprises a dispensing unit for the cleaning agent, which is driven by a driving means powered from a power source excluding a mains supply network, and a rotatable turbine wheel (6), which is rotatably driven by the air flow drawn by the vacuum cleaner through the tube (7). At least the brush is rotatably driven by the turbine wheel, wherein the device is formed such that the air flow is passing the turbine wheel when air is drawn through the air suction opening (11) as well as through the alternative air inlet (3). The invention also relates to a method for cleaning of carpets.

Description

A CARPET CLEANING DEVICE AND A METHOD FOR CLEANING A

CARPET

The present invention relates to a carpet cleaning device being adapted to clean carpets by means of a cleaning agent and being connectible to a vacuum cleaner provided with a hose and tube, comprising: a connecting structure for allowing connection to the vacuum cleaner; an elongated air suction opening, which is adapted to be facing the carpet to be cleaned and through which air can be drawn from the area adjacent the carpet surface to withdraw dirt from the carpet; a rotatably driven brush positioned in the air suction opening to accomplish agitation of the carpet surface, on one hand for enable working in of the cleaning agent between the carpet fibres, on the other hand to facilitate releasing of the cleaning agent together with dirt from the carpet, after a desired time period after application of the cleaning agent, to permit withdrawal by the air flow through the air suction opening; a valve means for allowing switching of the air flow between a suction state, when the air is drawn through the air suction opening to withdraw dirt and cleaning agent from the carpet, and a dispensing state when the air is drawn into the device through an alternative air inlet without passing through the air suction opening such that the cleaning agent is prevented from being removed from the carpet during dispensing and simultaneously agitation by means of the brush.

The invention also relates to a method for cleaning carpets. Background of the invention

Carpet cleaners for performing cleaning of carpets on-site by means of some form of cleaning agent, such as e.g. gel, fluid, powder or the like, are known in many different embodiments. Some of them are in form of special purpose machines, which are used to apply the cleaning agent, which, after sufficient acting time and possibly drying, can be removed together with dirt by means of a regular vacuum cleaner. However, there is a great advantage if the application of the cleaning agent as well as the subsequent removing of the cleaning agent and the dirt, can be performed with one and the same machine, not least for the sake of convenience. Therefore, it is known special purpose machines, which also has a vacuum cleaner incorporated. Unfortunately, such machines tend to become very expensive, especially in view of how seldom an individual normally has need for a carpet cleaning device. They also tend to be more heavy and bulky than regular vacuum cleaners, such that they are not well suited to be used also as an ordinary vacuum cleaner. Accordingly, such machines are as a rule intended exclusively for professional use.

Therefore it exists a need for a carpet cleaning device, which is in form of a comparatively small and inexpensive attachment that readily can be connected to an ordinary vacuum cleaner for cleaning of carpets when a need for this exists, and which can be disconnected from the vacuum cleaner such that it also can be used for conventional vacuum cleaning. However, many vacuum cleaners are in form of an "upright" -type including a stick, which in an upper end is provided with a handle and in a lower end is provided with an articulated nozzle unit. In an intermediate part, the vacuum cleaner has an electric motor, a fan for generating the suction air flow, a dust collecting bag and the like. The nozzle unit is as a rule connected to the vacuum cleaner in an integrated way, such that an exchange of the nozzle unit for a carpet cleaning device, can not be performed without a great deal of effort. However, most known special purpose machines for carpet cleaning, is formed as an upright-type, since this is advantageous in respect of driving of the rotatable brush and the automatic dispensing of the cleaning agent, due to the proximity to the electric motor and the electric power supply in the vacuum cleaner. A carpet cleaning device according to the introductory part of claim 1, is known from US 4 549 328. In that document is disclosed a power driven brush unit, which is adapted to be connected to a vacuum cleaner in form of a so called canister unit provided with a hose and tube. The brush is rotatable and located in the air suction opening of the unit. By means of a movable mounted shroud the air intake through the air suction opening can be shut off such that the brush may be used to work the cleaning powder into and agitate the carpet without the cleaning powder being sucked into the vacuum cleaner. During this working operation, the air to the vacuum cleaner is entered through a slide valve on the tube. After a desired acting time of the cleaning powder, the shroud is reset such that the air to the vacuum cleaner is entered through the air suction opening and the powder together with dirt can be withdrawn from the carpet into the vacuum cleaner during simultaneously agitation of the carpet by the brush.

However, the rotatably driving of the brush is performed by means of an electric motor in the unit which is powered by mains supply through an electrical cable arranged in the hose and tube. This has to result that the brush unit can not be made universally adaptable to any arbitrary vacuum cleaner having a hose and tube, since the vacuum cleaner must be provided with a power outlet, a cable in the hose and tube as well as some form of connecting means for electrical connection to the carpet cleaning device. A separate electric motor in the brush unit will probably also make the brush unit expensive to manufacture. Moreover, the brush unit is not provided with a powder dispensing unit for convenient dispensing of powder over the carpet at the same time as working the powder into the carpet by agitation by means of the brush. Instead, the powder dispensing has to be performed manually or by means of a separate dispensing unit .

Summary of the invention

It is an object of the invention to improve carpet cleaning devices for vacuum cleaners provided with a hose and tube. More precisely it is an object to provide a carpet cleaning device for a vacuum cleaner provided with a hose and tube for enabling convenient and readily cleaning of carpets, which is comparatively inexpensive to manufacture and which easily can be made universally attachable to any arbitrary vacuum cleaner equipped with a hose and tube. At least this object is achieved by a carpet cleaning device according to claim 1.

The invention also relates to a method for cleaning carpets, having essentially the same object as above. At least this object is achieved by a method according to claim 9.

The invention is thus based on the understanding that this object may be achieved by a carpet cleaning device, which is in form of an attachment to existing, conventional vacuum cleaners having a hose and tube and which is provided with a turbine wheel. The turbine wheel is driven by the air flow through the vacuum cleaner tube and the air intake to the turbine wheel may be shifted by means of a valve means such that it can be entered through a conventional air suction opening facing the carpet surface to be cleaned, for withdrawal of dirt and cleaning agent from the carpet into the vacuum cleaner, or through an alternative air inlet when the turbine wheel is driven, at the same time as dispensing of a cleaning agent, but no dirt or cleaning agent is drawn from the carpet. The rotation of the turbine wheel is utilized to rotatingly drive a brush located in the air suction opening for agitating of the carpet surface, on one hand when working in the cleaning agent into the carpet, on the other to agitate the carpet to facilitate withdrawal of dirt and cleaning agent from the carpet when the air is entered through the air suction opening. The carpet cleaning device also includes a dispensing unit for a cleaning agent for convenient dispensing of cleaning agent in the same working operation as agitating the cleaning agent into the carpet . The dispensing unit for the cleaning agent is driven by a driving means powered from a power source excluding a mains supply network. In this way neither the rotatable brush, nor the dispensing unit need any mains supply cable from the vacuum cleaner or from a wall socket, which makes it convenient and readily attachable to an arbitrary vacuum cleaner having a hose and tube. Since the carpet cleaning device do not need any mains supply cable from the vacuum cleaner, it is possible to adapt the carpet cleaning device to fit most available vacuum cleaners, having a hose and tube . Within this general idea, the invention may be modified and altered in many different ways within the scope of the claims. For example, it is preferred that also the dispensing unit for the cleaning agent is driven by the turbine wheel through a suitable driving means. However, it is also conceivable that the driving may be performed in other ways, e.g. by means of wheels, which bear against the carpet surface and are rotated when moving the carpet cleaning device over the carpet and the rotational movement is utilized to drive the dispensing unit. One advantage with such a solution is that the dispensing of the cleaning agent is terminated as soon as the user stops moving the carpet cleaning device, which precludes that any cleaning agent should be discharged on the carpet if the carpet cleaning device is hold stationary while the vacuum cleaner is still running. Another possibility is to mount a small electric motor in the carpet cleaning device which is powered by a battery. The power required for driving a dispensing unit is normally so low that a small and inexpensive battery powered electric motor should in most cases be sufficient . Also, the method for dispensing the cleaning agent from the carpet cleaning device can be performed in many different ways. In a hereinafter described, and in the drawings shown, embodiment of the invention, the dispensing unit comprises an elongated hopper containing a cleaning powder. In a lower surface of the hopper, it is provided with holes through which the powder is allowed to fall, preferably through the air suction opening, onto the carpet surface. The discharging of the powder is facilitated by vibrations in the carpet cleaning device, such as by means of an eccentric cam or an unbalanced rotating object, e.g. the turbine wheel. To regulate the amount of powder dispensed from the hopper, the carpet cleaning device is equipped with pins, which can be introduced from beneath into the holes to completely shut the holes or to open them to a desirable extent. However, powder dispensing could be performed in many different ways, such as by a driven belt which is moved through a container filled with powder to convey the powder out from the container and discharge it onto the carpet. It is also conceivable to dispense with a hopper or a container of any kind and instead make provisions to attach a package containing a cleaning agent, of e.g. cardboard or plastics, onto the carpet cleaning device . It is preferred that the cleaning agent is in form of a powder, since then the powder, after a desired acting time in the carpet, can be drawn into the vacuum cleaner together with dirt without any risk of damage to the vacuum cleaner. If a "wet" cleaning agent, such as a gel or a fluid, is used instead, it is a risk that the electric motor of the vacuum cleaner is damaged if the cleaning agent is drawn into the vacuum cleaner before the cleaning agent has dried. This is because in most vacuum cleaners, the air flow is passed by the electric motor. However, it would be conceivable to use also a wet cleaning agent, which preferably should be of a quick- drying type, if care is taken to let the cleaning agent dry sufficiently before it is drawn into the vacuum cleaner.

The invention is hereinafter described in relation to a vacuum cleaner of a canister-type having a canister unit including an electric motor, a fan and a dirt collecting means. However, it is to be understood that the invention is also applicable in a central vacuum cleaner system, having the vacuum cleaner unit built into a building and a hose and tube unit, which is connectible to suction terminals at various locations in the building.

It is preferred that the carpet cleaning device is made attachable to an existing hose and tube of a vacuum cleaner. However, it would also be conceivable that the carpet cleaning device is provided with its own tube, and possibly also its own hose, which is attachable to a vacuum cleaner.

The rotating brush is preferably an ordinary brush having a large number of wires, straws, yarn, or the like, projecting around its periphery. However, the brush could also be formed in other ways, e.g. being provided with a number of flexible lamellas extending in its longitudinal direction.

The turbine wheel in the hereinafter disclosed embodiment, is adapted for a general radial or tangential air flow. Of course the turbine wheel also could be of a type adapted for a general axial air flow. The valve means for shifting the air flow between the suction state and the agitation state, could of course be formed in many different ways. In the hereinafter described embodiment the valve means is in form of a displaceable valve, but it could of course also be e.g. rotatable or articulated. It is also possible to have detachable valve members, which are releasable from and mountable in the air passages of the carpet cleaning device. It is also conceivable to interconnect the regulating means for dispensing of the cleaning agent and the valve means, such that dispensing of cleaning agent is precluded at the same time as the valve means is set in the suction position.

Brief description of the drawings

An embodiment of the invention will hereinafter be described in detail with reference to the drawings, in which:

Fig 1 is a perspective view from above and behind of a carpet cleaning device according to the invention; Fig 2 is a perspective view according to fig 1 from above and the front ;

Fig 3 is an exploded and partly cut perspective view according to fig 1;

Fig 4 is a perspective view of a brush, its driving mechanism and regulator means for the air flow and powder dispensing;

Fig 5 is a schematic cross section through the carpet cleaning device in a powder dispensing state; and

Fig 6 is a schematic cross section according to fig 5 but in a powder and dirt suction state.

Detailed description of an embodiment of the invention

Fig 1 and 2 of the drawings depicts the exterior appearance of a carpet cleaning device according to an exemplary embodiment of the invention. The overall design of the carpet cleaning device is more or less like an ordinary nozzle unit for a vacuum cleaner, having a tubular connection sleeve 1 adapted to be connected to an outer end of a tube of a vacuum cleaner provided with a hose and tube. However, the carpet cleaning device is somewhat different from an ordinary nozzle unit, since it also comprises a lid 2 covering a powder containing compartment, an alternative air inlet 3 and adjustable levers 4, 5 for switching air intake and controlling of the powder dispensing, respectively, to be explained more in detail below.

Now reference is made to figs 3 to 6, from which the mechanical structure of the device can be seen in detail. A radial flow turbine wheel 6 is arranged in a rear portion of the carpet cleaning device, just in front of the connection sleeve 1, and is rotationally driven by the air flow through a vacuum cleaner tube 7 connected to the sleeve. The turbine wheel is connected to a rotary shaft 8, which is rotationally journalled by a bearing sleeve 15. A driving belt 9 is laid over a drive pulley in the outer end of the rotary shaft 8 and a corresponding drive pulley in an outer end of a rotary brush 10. Accordingly, the brush is rotationally driven by the turbine wheel 6. The brush 10 is located at an air suction opening 11 in a lower front portion of the device such that the carpet can be agitated by means of the brush when it is rotating. By means of a valve means 12, the air intake to the vacuum cleaner can be shifted between air intake through the air suction opening 11 and the alternative air inlet 3.

The valve means 12, which is best seen in fig 4, is elongated and is formed with a generally horizontal portion 12' and a generally vertical portion 12''. The valve means 12 can be displaced sideways by operating the lever 4, such that either the horizontal portion 12' or the vertical portion 12'' is positioned at the air intake to the turbine wheel 6. When the horizontal portion 12' is positioned at the air intake to the turbine wheel, as is illustrated in figs 4 and 6, the air passage from the alternative air inlet 3 is closed and the air is drawn through the air suction opening 11 past the brush 10, i.e. the device is now in a suction state, wherein dirt and powder can be drawn from the carpet. When, on the other hand, the vertical portion 12'' is positioned at the air intake to the turbine wheel, as is illustrated in fig 5, the air passage from the air suction opening 11 is closed and the air is drawn through the alternative air inlet 3 on the upper surface of the device, i.e. the device is now in a powder dispensing state when the powder is worked in between the fibres in the carpet without any air drawn through the air suction opening 11.

In the powder dispensing state, the powder is dispensed from a hopper 13 through holes 14 formed in the bottom in the lowest part of the hopper, such that the powder falls at the side of the brush 10 down onto the carpet and can be worked into the carpet by means of the brush. To facilitate dispensing of the powder through the holes 14 in the bottom of the hopper 13, the device is provided with an unbalance vibrator in form of a not in the drawing shown weight on one of the turbine blades. In this way, the carpet cleaning device will be exposed to small vibrations, which will assist in transporting the powder in the hopper 13 towards the holes 14.

The dispensing of the powder can be started and terminated and the amount of powder regulated by operating the lever 5 sideways. This will, by means of a not in detail shown mechanism, actuate a powder regulating ledge 16 to be displaced upwards or downwards. The lower edge of the ledge 16 is provided with upward directed pointed pins 17, corresponding in size and position to the holes 14 in the bottom of the hopper 13. Accordingly, when displacing the ledge 16 to an uppermost position, the tips of the pins 17 will be displaced into the holes and shut off the powder dispensing. When, on the other hand, displacing the ledge 16 in a downward direction, the holes will open such that the powder can fall out through the holes and the powder dispensing will gradually increase as the ledge is displaced further downwards and reach its largest amount in the lowermost position of the ledge.

In figs 5 and 6 of the drawings, is also shown one of totally two wheels 18, which are arranged to facilitate moving of the carpet cleaning device over a carpet .

Claims

1. A carpet cleaning device being adapted to clean carpets by means of a cleaning agent and being connectible to a vacuum cleaner provided with a hose and tube (7), comprising: a connecting structure (1) for allowing connection to a vacuum cleaner; an elongated air suction opening (11) , which is adapted to be facing the carpet to be cleaned and through which air can be drawn from the area adjacent the carpet surface to withdraw dirt from the carpet; a rotatably driven brush (10) positioned in the air suction opening to accomplish agitation of the carpet surface, on one hand for enable working in of the cleaning agent between the carpet fibres, on the other hand to facilitate releasing of the cleaning agent together with dirt from the carpet, after a desired time period after application of the cleaning agent, to permit withdrawal by the air flow through the air suction opening (11) ; a valve means (12) for allowing switching of the air flow between a suction state, when the air is drawn through the air suction opening (11) to withdraw dirt cleaning agent from the carpet, and a dispensing state when the air is drawn into the device through an alternative air inlet (3) without passing through the air suction opening such that the cleaning agent is prevented from being removed from the carpet during dispensing and simultaneously agitation by means of the brush; c h a r a c t e r i z e d in that the device also comprises : a dispensing unit for dispensing of a cleaning agent, which is driven by a driving means powered from a power source excluding a mains supply network, for controlled discharging of the cleaning agent to the carpet ; and a rotatable turbine wheel (6) , which is rotatably driven by the air flow drawn by the vacuum cleaner through the tube (7) ; wherein at least the brush (10) is rotatably driven by the turbine wheel (6) via a driving mechanism, and wherein the device is formed such that the air flow is passing the turbine wheel in the suction state as well as in the dispensing state so as to accomplish rotational driving of the brush in both states.

2. A carpet cleaning device according to claim 1, c h a r a c t e r i z e d in that also the driving means for dispensing of the cleaning agent is driven by the turbine wheel (6) .

3. A carpet cleaning device according to claim 1 or 2, c h a r a c t e r i z e d in that the carpet cleaning device is adapted for a cleaning agent in form of a powder .

4. A carpet cleaning device according to claim 3 , c h a r a c t e r i z e d in that the carpet cleaning device includes a powder containing compartment in form of a hopper (13) having holes (14) in a lower portion.

5. A carpet cleaning device according to claim 4 , c h a r a c t e r i z e d in that a powder regulating means includes pins (17) , which can be introduced from beneath into the holes (14) of the hopper (13) .

6. A carpet cleaning device according to any of the claims 3-5, c h a r a c t e r i z e d in that the powder feeding is accomplished by means of vibrations.

7. A carpet cleaning device according to claim 6, c h a r a c t e r i z e d in that the vibrations is generated by means of the rotating turbine wheel (6) .

8. A carpet cleaning device according to any of the claims 1-7, c h a r a c t e r i z e d in that the valve means is in form of a displaceable valve member (12) having a generally horizontal portion 12' and a generally vertical portion 12''.

9. A method for cleaning of carpets by means of a cleaning agent, comprising the steps of: using a vacuum cleaner of a type having a hose and tube (7) , through which air is drawn to withdraw dirt from the carpet ; connecting a carpet cleaning device to the vacuum cleaner, having a rotatable brush (10) at an elongated air suction opening (11) in a downward facing surface of the carpet cleaning device, a dispensing unit for the cleaning agent, a rotatable turbine wheel (6) driven by the air flow through the vacuum cleaner tube, a valve means (12) for switching the air intake between a suction state, when the air is drawn via the air suction opening (11) and past the turbine wheel (6) , and a dispensing state, when the air is drawn via an alternative air inlet (3) such that the air flow does not pass the brush but still passes the turbine wheel; setting the valve means (12) in the dispensing state for dispensing the cleaning agent over the surface of a carpet to be cleaned, and simultaneously rotatingly driving the brush (10) by means of the turbine wheel (6) , which is driven by the air flow drawn through the vacuum cleaning tube, to accomplish agitation of the carpet surface to work in the cleaning agent between the carpet fibres; letting the cleaning agent act on the carpet for a desired time period; setting the valve means (12) in the suction state and terminating the dispensing of the cleaning agent, for performing of suction of dirt and cleaning agent from the carpet during simultaneously agitation of the carpet by means of the brush (10) to facilitate releasing of dirt and cleaning agent from the carpet .

10. A method according to claim 9, comprising the further step to drive also the dispensing unit by means of the turbine wheel (6) .