DEVICE FOR A CYCLONE VACUUM CLEANER The present invention relates to a device for a vacuum cleaner having a cyclone separator which is connected to a vacuum source, the cyclone separator including a mainly cylindrical cyclone housing having an inlet through which dust laden air is drawn tangentially into the cyclone housing, an intermediate part arranged below the cyclone housing and having a liner shaped as a hollow up-side-down truncated cone with a lower opening facing toward a collecting container arranged below the intermediate part, and an outlet arranged centrally in the cyclone housing.

Vacuum cleaners which include cyclone separators are known in the art. A disadvantage with such vacuum cleaners is that emptying of the collecting container is unhygienic work since the container, when being removed from the vacuum cleaner, typically has an open structure which permits the dust to whirl up into the air when the container is turned up-side-down during the emptying operation. Moreover, dust tends to stick to the inner surfaces of the container, which means that such surfaces have to be manually cleaned or wiped.

Vacuum cleaners of the above-mentioned type can also be used as so called wet cleaners in order to remove a liquid cleaning agent together with dirt from a floor. The liquid and dirt are separated by the cyclone and collect in the container. The presence of liquid has a positive effect since the dust is entrained in the liquid, and reduces the above-described emptying problems relating to whirling dust. However, if relatively large amounts of liquid are collected in the container the container will become heavy. The container also has to be emptied after each use since bacteria grows rapidly in wet environments and tends to cause odor and hygiene problems.

The present invention is directed toward a device which makes it possible to use the vacuum cleaner in a conventional way within the household in order to clean up dust and dirt particles while also making it possible to empty the container without dust

whirling up during the emptying operation.

In accordance with the present invention, a vacuum cleaner includes a cyclone separator having a cyclone housing with an inlet and a liner. Dust laden air is drawn into the cyclone housing via the inlet, and dirt is centrifugally separated from air and falls down through an opening in the liner into a collecting container. A liquid tank is connected to supply liquid to the cyclone separator. The liquid supplied to the cyclone separator helps to entrain the dust and particles in the container.

In further accordance with the present invention, the liquid tank is connected to the cyclone housing inlet by means of a tube connection. Air flowing through the inlet serves to draw liquid from the tank, through the tube connection and into the cyclone separator. A valve is provided to control fluid flow through the tube connection.

These and further features of the present invention will be apparent with reference to the following description and drawings, wherein: FIG. 1 is a schematic vertical view showing a vacuum cleaner provided with a cyclone separator including a device according to the invention; FIG. 2 is a partly broken vertical view through the cyclone separator; FIG. 3 is a plan view of the cyclone separator shown in FIG.

2; FIG. 4 is a section on the line IV-IV in FIG. 2.

With reference to FIG. 1, a vacuum cleaner comprising a vacuum cleaner housing 10 enclosing a vacuum source designed as a motor-fan unit 11 is illustrated. The inlet side of the fan is connected to a cyclone separator 12 arranged at a front part of the vacuum cleaner. The cyclone separator 12 via a hose 13, a tube handle 14 and a tube shaft 15, communicates with a nozzle 16.

With reference to FIGS. 2-4, the cyclone separator 12 has an inlet part 17 with a sleeve 18 to which the hose 13 is connected, an outlet part 19 with an opening 20 which is connected to the inlet side of the fan, and first and second cyclones connected in

series between the inlet part 17 and the outlet part 19.

The first cyclone comprises a first cyclone housing 21 having a circular cross section into which air flows tangentially through a first inlet 22. The cyclone housing 21 supports an annular liner 23 designed as a hollow, truncated, up-side-down cone having a centrally arranged first inlet opening 24. The cyclone housing 21 extends below the liner 23, and has a lower end forming a circular flange part 25 which is received in a sleeve-shaped enlargement 26 of a cylinder shaped container 27.

The first cyclone is also provided with a first outlet 28.

The first outlet 28 comprises several openings arranged at the periphery of a circle spaced radially inwardly from the cyclone housing 21. The openings forming the first outlet 28 continue into gradually narrowing channels 29, each of the channels 29 having side walls formed by two adjacent plate-shaped elements 30 which are secured between an upper annular plate 31 and a lower annular plate 32. The upper plate 31 also forms a roof part of the first cyclone housing 21.

The upper plate 31 supports a second cyclone housing 33 for the second cyclone. The second cyclone housing includes an upper cylinder shaped part 34 which is surrounded by the lower annular shaped plate 32. The second cyclone housing 33 extends downwardly through the opening 24 in the liner 23. Relatively beneath the liner, the cyclone housing 33 also has a lower tube-shaped part 35 with a gradually decreasing diameter. The tube-shaped part 35 defines a second opening 36 which faces toward the container 27.

A flap member 37 is pivotally secured to the tube-shaped part 35 adjacent to the periphery of the second opening 36 by means of a hinge 38.

The outlet openings 28 of channels 29 lead to second inlet openings 39 formed in the upper cylinder shaped part 34 which are directed tangentially with respect to the second cyclone housing 33. The channels 29 are directed such that the air flow direction in the second cyclone is reversed with respect to the air flow direction in the first cyclone. The second cyclone also has a second outlet 40 which is a central circular opening in the upper plate 31. The second outlet 40, via the tube-shaped outlet part

19, is connected to the opening 20.

The container 27 receives a circular plate 41 which, by means of widely spaced-apart distance means 42, is spaced above a bottom wall 43 of the container 27, thereby creating a chamber or space 44 between the plate 41 and the bottom wall 43. The plate 41, which may be perforated, has a somewhat smaller diameter than the inner diameter of the container 27 such that a peripheral slot or gap 45 is defined between the container side wall and the plate 41.

The chamber 44 is, by means of a nipple 46 and a tube connection 47, fluidly connected to a valve 48 secured to the outlet part 19. The valve is controlled by a control means 49.

The valve 48 is also, via a tube connection 50, connected to the outlet part 19. Accordingly, when the valve 48 is in an open position the chamber 44 is in fluid communication with the outlet part 19.

The container 27 receives a bag 51 made of an air impermeable material, such as plastic. The bag 51 is clamped between the enlargement 26 of the container 27 and the flange part 25 of the cyclone housing, as illustrated, and thereby effectively seals the upper end of the space between the bag 51 and the container 27.

On the flange part 25 of the cyclone housing and the container 27 there are a plurality of hooks 52 on which a liquid tank 53 is supported. The tank 53 is provided with a tube 54 extending from near a bottom 55 of the tank through an upper wall 56 of the tank and, via a valve 57, to an inlet opening 58. The inlet opening 58 issues into the inlet part 17. The tube 54 is connected to the inlet part by means of a coupling 59. The inlet opening 58 is preferably arranged in a narrowing section 60 of the inlet part 17 such that an injector is formed (FIG. 4). The tank 53 is also provided with a refill opening which is normally covered by a cover 61.

The device operates in the following manner. When the vacuum cleaner is started an under-atmospheric pressure is created in the cyclone separator which means that the turbulence of the air causes the flap member 37 to initially pivotally oscillate.

Thereafter, the pressure differential between the first and second

cyclones causes the flap member to pivotally close to seal the second opening 36. At the same time, dust laden air is drawn into the cyclone separator through the inlet part 17.

The air flows via the tangentially directed opening 22 into the first cyclone housing 21 and creates a first vortex which surrounds the cylinder part 34 of the second cyclone housing 33.

Centrifugal forces in the first vortex tend to through particles radially outwardly toward an inner periphery of the first cyclone housing 21. The centrifugally separated particles fall, due to gravity, downwardly through the opening 24 in the liner 23 and into the bag 51 inserted in the container 27. At the same time, partially cleaned air from the more central portion of the first vortex flows through the first outlet 28 and the channels 29 and into the second cyclone housing 33 through the second inlet openings 39 to create a second vortex therein.

The channels 29 are directed such that the second vortex air flow is reversed 1800 relative to the first vortex air flow. Due to inertia of the particles and the rapid change of air flow direction, a substantial majority of the particles entrained in the first vortex will remain in the first vortex in the first cyclone. Since the second inlet 39 is tangentially directed with respect to the second cyclone housing 33, the second vortex has a smaller diameter and rotates in an opposite direction as compared to the first vortex.

In the second cyclone housing 33 additional particles are centrifugally separated, and these separated particles fall down and collect on the flap member 37. Cleaned air exits the second cyclone housing via the second outlet 40 and flows into the outlet part 19 from which it, via the opening 20, and also via optional, mechanical filters (not shown) escapes to the motor-fan unit 11.

When the vacuum cleaner is shut off there will be a pressure equalization between the spaces on each side of the second cyclone housing 33 which means that the flap member 37, because of its own weight and the weight of particles thereon, will pivot downwardly to a vertical position. Accordingly, particles resting on the flap member will fall down into the bag 51.

Before the vacuum cleaner is emptied after one or, usually,

several cleaning operations, and while it is still running, the valve 57 is opened. An under-atmospheric pressure created by the injector draws the liquid, which preferably is water, from the tank 53 into the air flowing through the inlet part 17. Liquid particles are then separated from the air in the cyclone and fall down into the container and bind the dust in the container.

When the vacuum cleaner has been shut off, the container can be emptied by removing the container 27 from the flange part 25 of the cyclone separator whereby the bag 51 together with the collected particles can be lifted out from the container and be thrown away without the dust whirling around. When inserting a new bag in the container, the bag 51 is clamped between the flange part 25 and the upper part of the container 27 and then the vacuum cleaner is started. Normally, the valve 48 is in an open position. Accordingly, an under-atmospheric pressure is established in the chamber 44 and air which is present between the bag and the container wall will be drawn out through the tube connection 47, 50 and thereby cause the bag 51 to abut the container wall and the plate 41.

It is of course possible to use devices according to the present invention for binding dust in other types of cyclone vacuum cleaners than for the type which has been described above and to use the collecting container without the bag which has been described above. In the shown embodiment the valve 48 is closed if a bag is not used.