The present invention is directed to a cyclone dust separator unit, a cyclone vacuum cleaner and a method of manufacturing a cyclone dust separator.

Cyclone type vacuum cleaners are widely known because of their benefit in bagless dust collection.

Dust separating units of known cyclone type vacuum cleaners often have comparatively cumbersome and complicated mechanical de signs requiring comparatively high assembly and manufacturing efforts .

Therefore, it is one of the objects of the present invention to solve the problems observed with state of technology. In particular, a cyclone dust separator unit, shall be provided, which has a comparatively simple mechanical design and can easily be assembled. Further, under similar considerations, a cyclone type vacuum cleaner and a method of manufacturing a cyclone dust separator unit shall be provided. These and further objects are solved by the features of claims

1, 8 and 10. Embodiments and variants result from respective dependent claims .

According to claim 1, a eyelone dust separator unit for a cy- clone type vacuum cleaner is provided. The cyclone dust separa- tor unit comprises at least two functional subunits.

Here, a functional subunit shall in particular be understood to be a component part of the cyclone dust separator taking over a function and/or being involved in dust separation. A component part in particular may be one or a group of cyclone tanks or cy- clone cups or funnels, one or a corresponding group of air guid- ing elements, an end-cap or closure and the like.

Preferably, each functional subunit, even and in particular if it comprises several sub-elements, is implemented as a one-piece part, i.e. is of integral design.

With the proposed cyclone dust separator unit it is provided, that an air-tight seal between the at least two functional subu- nits is established by at least one bonded connection.

By using bonded connections, it is possible to obtain in a com ^¬ paratively and straight forward way air-tight connections be ^¬ tween respective component parts. Further, in using bonded con- nections, comparatively robust connections and therefore robust designs of the cyclone dust separator unit can be obtained.

An additional advantage is that in using bonded connections, the air-tight connections between respective functional subunits can be established comparatively quickly. Therefore corresponding manufacturing processes can be enhanced and conducted cost effi ^¬ ciently .

It shall be noted, that in using bonded connections as proposed herein, comparatively costly and complicated sealing systems as used in the state of the art and often requiring special sealing elements, numberless screws for fixing purposes and other me ^¬ chanical elements can be dispensed with. In general, respective functional subunits of cyclone dust sepa ^¬ rator units for cyclone type vacuum cleaners are made from plas ^¬ tic materials. Bonding connections, in particular comprising at least one of a welding and adhesive bond, in particular glued connection or joint, can readily be used for these materials.

In a preferred embodiment, the bonded connection comprises at least one of a welding, a welded connection and an adhesive bond, in particular at least one of a welded and adhesive seam, between the at least two different functional subunits. As al ^¬ ready indicated, welding and/or adhesive bonding, in particular gluing, is readily available for plastic materials in general used for respective subunits. Further, establishing of welded and/or adhesive bonded connections between respective plastic parts is comparatively easy and fast, leading to simplified and cost-efficient manufacturing processes. In a further embodiment, it is provided that at least one of the at least one bonded connection is established at least one of circumferentially along at least a section of a contact surface and along at least a section of a common contact line of at least two of the subunits .

The common contact line may run circumferentially along at least a section of the functional subunits. However, the contact line may run along any line across and/or within a surface or edge of the functional subunit. The contact lines or contact surfaces in general constitute sections of the functional subunits, along which or within which air-tight seals have to be established. However it shall be noted, that also non-bonded contact lines or contact surfaces may be present. In one further embodiment, the cyclone dust separator unit com ^¬ prises as functional subunits at least one cyclone base unit and at least one air guiding unit .

The cyclone base unit may for example comprise several cyclone elements, in particular cyclone funnels or cyclone cups, in or by which dust separation via the cyclone-effect is effected.

The air guiding unit is provided for guiding air within the cyclone dust separator unit, in particular within or inside the cyclone elements or cyclone funnels or cyclone cups. In particu ^¬ lar, the air guiding unit may be provided for establishing an airflow within the cyclone dust separator reguired, or at least favorable, for generating the cyclone-effect and for feeding and removing air to and from respective cyclone elements of the cyclone dust separator unit .

The air guiding unit may for example comprise a cover plate for covering a top opening of a cyclone element, in particular cyclone funnel, and a tubular element reaching through the center of the cover plate into the cyclone element or cyclone funnel. A cyclonic airflow can be generated within the cyclone element around the tubular element, for example, if air enters the cyclone element in a tangential direction. The opening provided by the tubular element functions as an air outlet.

With the present embodiment, a first bonded connection is estab lished between the at least one cyclone unit and the at least one air guiding unit . In this way, and in particular by providing a suitable bonded connection, in particular as described further above, it can be prevented that incoming, uncleaned air passes by and does not enter the cyclone unit, e.g. a cyclone element .

The first bonded connection preferably is at least one of a welded and adhesive bonded, i.e. glued, connection, providing an air-tight seal between the cyclone base unit and the air guiding unit .

In particular it is possible to establish an air-tight seal between the cover plate and the cyclone element, in particular an upper rim of the cyclone element. Here, a circumferential welding and/or adhesive seam, in particular gluing seam, can be used for example, in particular running along the contact line between the cyclone element and cover plate.

Connecting the cyclone base unit and the at least one air guiding unit via the first bonded connection can be done in comparatively guick manufacturing steps, in turn lowering the costs for the overall manufacturing process and cyclone dust separator unit .

In particular and in contrast to state of the art systems, it is not mandatory to mount sealings and fix screws to seal the air guiding unit against the cyclone base unit.

In one variant of the cyclone dust separator unit, the cyclone base unit comprises several cyclone elements and the air guiding element comprises a corresponding number of air guiding elements, wherein each cyclone element at least partially accommo ^¬ dates one air guiding element and the first bonded connection is implemented at a circumferential edge of the air guiding unit along a contact line between the air guiding unit and cyclone base unit.

In particular with such integrated, and m particular comparatively complex parts, air-tight connections can be established comparatively easy as compared to solutions reguiring conven ^¬ tional seals. Further, in using circumferential connections, in particular at least one of weldings and adhesive bondings, the cyclone chambers can be effectively provided with air-tight seals. In addition a stepwise assembly of the cyclone dust sepa ^¬ rator in which bonded connections, in particular weldings and/or adhesive bondings, for example gluing connections, are used, makes it possible to integrate all necessary and different ducts, air guides and air channels in a single part, i.e. tool, such as the cyclone dust separator unit. In particular the bonded connection can be applied to compara ^¬ tively complex cyclone dust separator units. Such cyclone dust separator units may be of a configuration in which the cyclone base unit comprises a first group of cyclone elements and a se ^¬ cond group of cyclone elements . The cyclone elements of each group, i.e. of the first group and the second group, may be ar ^¬ ranged in a line, while longitudinal axes of the cyclone ele ^¬ ments of each group may be oriented parallel to each other. The first and second group of cyclone elements may be arranged in a U- or V-shaped configuration.

A U- or V-shaped configuration in particular shall mean that the cyclone elements of the first and second group are arranged and aligned essentially along and in particular parallel to limbs of the U- or V-shape.

The embodiment and variant comprising a V- or U-shape can be considered a highly integrated cyclone dust separator unit, which may for example be used for a secondary dust separation stage of a cyclonic vacuum cleaner. Despite the comparatively complex construction of the cyclone dust separator unit, the proposed bonded connection enables a straight forward, efficient and cheap manufacture of the cyclone dust separator.

It shall be noted again, that the cyclone base unit and the air guiding unit may be implemented as one-piece parts. This may in particular be applied to the cyclone base unit in U- or V-shape configuration.

In an embodiment it is provided, that the cyclone dust separator further comprises as a functional subunit at least one cyclone head unit. The cyclone head unit in particular is adapted to cover the top part of single cyclone elements already connected to the air guiding unit, i.e. to corresponding air guiding elements . In particular the cyclone head may provide an air duct or an air chamber connecting an air outlet of an air guiding element to an air outlet of the cyclone dust separator unit.

In the previous embodiment, it may be provided that at least one second bonded connection is established at least one of between the cyclone head unit and the cyclone base unit and between the cyclone head unit and the air guiding unit. In doing so, a two- stage manufacturing process may be used, in which in a first stage all the necessary air-tight seals between cyclone base unit and air guiding unit, and in a second stage all the neces- sary air-tight seals to the cyclone head are established. It has shown that implementing multi-stage, in particular two-stage, manufacturing processes is effective for manufacturing cyclone dust separator units with highly integrated air ducts, ductings and chambers, in particular reguired for effectively operating a cyclone dust separator.

As can be seen, the proposed cyclone dust separator unit enables comparatively easy and cost efficient manufacturing processes. Further, comparatively complex cyclone dust separator units can be assembled and designed at acceptable effort and cost.

According to claim 8, a cyclone vacuum cleaner is proposed. The cyclone vacuum cleaner comprises at least one cyclone dust sepa rator unit according to any of the above mentioned embodiments and variants. As to advantages and advantageous effects, reference is made to the description above and further below.

In one embodiment of the vacuum cleaner, the cyclone dust sepa- rator unit is implemented as a secondary stage cyclone dust separator connected downstream of a primary stage cyclone dust separator. As a secondary stage dust separator, the cyclone dust separator unit may in particular be implemented in a configuration as described above, in which the cyclone base unit compris- es two groups of cyclone elements arranged or oriented in a V- or U-shape .

According to claim 10, a method of manufacturing a cyclone dust separator unit for a cyclone type vacuum cleaner is proposed. According to the method an air-tight seal between at least two functional subunits of the cyclone dust separator is established via at least one bonded connection. As to advantages of the method, reference is made to the description above. It shall be noted that the bonded connection can substitute conventional sealing systems as mentioned further above. In addition, the method allows a comparative easy and cost efficient manufacture of the cyclone dust separator unit. In an embodiment of the method, at least one of a welded connec ^¬ tion and adhesive bonded connection, in particular a gluing connection, between the at least two subunits is generated as the bonded connection. The bonded connection in particular may be a welding, adhesive bonding, welded seam and/or adhesive seam provided between respective subunits of the cyclone dust separator unit. Further reference is made to the description above. In a yet further embodiment of the method, it is provided that the cyclone dust separator comprises as functional subunits at least one cyclone base unit and at least one air guiding unit. Further, it is provided that the at least one air guiding unit and cyclone base unit are first put together, i.e. assembled. Then, a first bonded connection, representing at least one of the at least one bonded connection, is established between the cyclone base unit and air guiding unit . Such a manufacturing process allows a comparatively easy assembly even for compara ^¬ tively complex cyclone dust separating units, including air ducts, ductings and air chambers or openings.

According to a variant embodiment of the method it is provided that the first bonded connection, in particular at least one of a welding and adhesive connection, is established, i. e. gener- ated, circumferentially along at least a section of the air guiding unit. Here, particular reference is made to the descrip ^¬ tion further above which applies mutatis mutandis. In particu ^¬ lar, the bonded connection may be generated along at least a section of a contact surface and/or along a contact line of re- spective subunits.

In a yet further variant, in which the cyclone dust separator additionally comprises as a functional subunit at least one cy clone head unit, it is provided that in a further step the cy ^¬ clone head unit is assembled to the cyclone base unit and air guiding unit already bonded together in a previous step. Then a second bonded connection, constituting one of the at least one bonded connection is established at least one of between the cyclone head unit and the cyclone base unit and between the cyclone head unit and the air guiding unit.

The proposed two-step manufacturing, i.e. welding and/or adhesive bonding or gluing process is effective in obtaining ade- guate air-tight seals. Further, cyclone dust separating units may be manufactured comprising a great variety of integrated air ducts, ductings and air chambers reguired for effective dust separation .

In a further embodiment of the method it is provided that the at least one bonded connection is established at least one of cir- cumferentially along at least a section of a contact surface and along at least a section of a common contact line of at least two of the subunits. The common contact line may be located at a circumference, border or edge of at least one of the functional subunits. For further details, reference is made to the descrip- tion further above.

Embodiments of the invention will now be described in connection with the annexed figures, in which. FIG. 1 shows an exploded view of a cyclone dust separator unit ;

FIG. 2 shows a detailed view of a cyclone base unit;

FIG. 3 shows a detailed view of an air guiding unit;

FIG. 4 shows a detailed view of a cyclone head unit;

FIG. 5 shows the cyclone base unit and air guiding unit in the assembled state; FIG. 6 shows a cross sectional view of the cyclone dust separator unit in the assembled state;

FIG. 7 shows a bottom view of the cyclone dust separator

unit; and

FIG. 8 shows a perspective view of a cyclone type vacuum

cleaner .

FIG. 1 shows an exploded view of a cyclone dust separator unit 1. The cyclone dust separator unit 1 in the present embodiment comprises a cyclone base unit 2, a pair of air guiding units 3 and a pair of cyclone head units 4. The cyclone base unit 2, the air guiding units 3 and the cyclone head units 4 constitute functional subunits of the cyclone dust separator unit 1.

The cyclone base unit 2 comprises two groups of cyclone elements 5. The two groups of cyclone elements 5 are arranged in a sym- metric way with respect to a center plane of the cyclone base unit 2. Each group of cyclone elements 5 comprises five cyclone elements 5 arranged in a line respectively running perpendicular to the longitudinal direction of the cyclone elements 5. The cyclone base unit 1, in particular the arrangement of the two groups of cyclone elements 5, makes up a V- or U-shaped configuration .

The cyclone base unit 2, as well as the other functional subunits, are implemented as one piece parts, and are manufactured from a plastic material.

The cyclone elements 5 of the cyclone base unit 2 respectively comprise cyclone funnels 6, in the end constituting vortex or cyclone chambers, which respectively have an air inlet 7 pres- ently implemented as a longitudinal slot and adapted to deliver air into the cyclone funnels 6 in a tangential direction in order to establish a vortex or cyclone type airflow. The bottom part of the cyclone elements 5 may be closed by a further functional subunit, such as a bottom cover element (not shown), for example.

The upper part of the cyclone elements 5 has a cylindrical shape, into which air guiding elements 8 of a respective air guiding unit 3 are, at least partially, inserted. The air guid ^¬ ing elements 8 of the air guiding units 3 respectively are ar- ranged in a line essentially corresponding to those of the cy ^¬ clone elements 5. Each air guide unit 3 is implemented as a one piece part, such that each group of cyclone elements 5 can be eguipped with a corresponding air guiding element 8 in a single manufacturing step.

Each air guiding element 8 comprises a type of cover plate 9 and a short duct 10 reaching through the cover plate 9 and adapted to protrude into the cyclone element 5 in the assembled state. A cyclonic air flow is generated in particular around the short duct 10 within the cyclone element 5, and air leaves the cyclone element 5 via the short duct 10.

From the short ducts 10, air then enters a chamber established above each cyclone element 5 by corresponding caps 11 of the cy- clone head unit 4. From the caps 11, air enters into outlet openings 12 which in the present case have a rectangular shaped cross section.

Further reference is made to FIG. 2 to FIG.4 which show the functional subunits in more details .

In order to obtain an optimal separating efficiency and a proper airflow within the cyclone dust separator unit 1, in particular into the cyclone elements 5, from the cyclone elements 5 over the air guiding elements 8 into the caps 11 and from there to the outlet openings 12, adeguate air-tight sealings between re ^¬ spective functional subunits are reguired. In state of the art technology, conventional sealing elements with screw type fastening have been used, which is comparatively complex and expensive and reguires time consuming assembly.

According to the invention, it is provided, that air-tight sealings between respective functional subunits are implemented by bonded connections. The bonded connection may be any of a welded connection, in particular a welded seam between two func- tional subunits and/or a respective adhesive connection or adhe ^¬ sive seam.

In the present example, after assembling the air guiding unit 3 to the cyclone base unit 2, a first bonded connection in form of a welding is established in a first step. The welding is estab ^¬ lished between the cyclone base unit 2 and the air guiding unit 3 along a circumferential contact line thereof. In more detail, a welding is provided at the edge of the air guiding unit con ^¬ tacting upper edges of the cyclone base unit 2, in particular cyclone elements 5. A corresponding assembled state can be seen from FIG. 5 showing the cyclone base unit 2 mounted to the air guiding unit 3. Note that the welding may be substituted or com ^¬ bined with an adhesive bond, i.e. a gluing connection. As becomes obvious, providing welded and/or adhesive bonded air ^¬ tight connections between the cyclone base unit 2 and the air guiding unit 3 is comparatively easy and greatly simplifies as ^¬ sembly of the cyclone dust separator 1. Further, the bonded con ^¬ nections in particular contribute to a comparatively robust con- struction.

At the assembly stage obtained as shown in FIG. 5, the cyclone head unit 4 is mounted to, e.g. put onto the cyclone base unit 2 and air guiding unit 3. Then, in a second welding and/or adhesive bonding procedure, a second bonded connection between the cyclone head units 4 and the cyclone base unit 2 and air guiding units 3 is established. In more detail, a welding and/or adhe- sive bonding is established in the region of the upper circular sections of the cyclone head unit 4 and in the region of the sguare shaped outlet openings 12. As a result, the cyclone dust separator unit can be assembled with appropriate air-tight seals in two, comparatively simple welding and/or adhesive bonding, i.e. gluing, steps. In total, five functional subunits of the cyclone dust separator unit 1 can be assembled and welded and/or glued together in only two welding and/or gluing steps. This in turn leads to low manufacturing costs .

FIG.6 shows a cross sectional view of the cyclone dust separator unit in the assembled state. First weldings Wl between the cy- clone base unit 2 and the air guiding unit 3 and second weldings W2 between these elements and the cyclone head unit 4 are indicated in FIG. 6 by respective arrows. Note that the weldings Wl and W2 can be substituted and/or combined with adhesive

bondings .

With the air-tight bonded connections, i.e. weldings Wl and W2 or as appropriate adhesive bondings, an airflow tangentially into the cyclone elements 5, out of the cyclone elements 5 via the short duct 10 and from the short duct 10 into the cap 11 and from there to the outlet opening 12 can be obtained, notably without any conventional sealing elements.

FIG. 7 shows a bottom view of the cyclone dust separator unit 1. As can be seen, the cyclone dust separator unit 1 is of compara- tively compact and robust design, in particular in regions of the cyclone elements 5. From FIG. 7, the air inlet section 13 and the air outlet section 14 to and from the cyclone elements 5 can be seen at the bottom side of the cyclone base unit 2.

Bottom openings of the cyclone elements 5 are in ordinary use covered by cover elements (not shown) . The cyclone dust separator unit 1 as shown throughout the figures can be and preferably is used as a secondary stage dust separator in a cyclone type vacuum cleaner .

A respective cyclone type vacuum cleaner 15 is shown in FIG 8, where the cyclone dust separator unit 1 is used as a secondary step dust separator. The cyclone dust separating unit 1 in the present configuration of the vacuum cleaner 15 is mounted to a front section of the vacuum cleaner 15. Air exiting a first stage cyclone unit (not shown) is guided via ductings 16 to the respective groups of cyclone elements 5 arranged at both lateral sides of the vacuum cleaner 15.

In all, it can be seen, that the proposed cyclone dust separating unit 1 provides a compact and robust design, and can be manufactured in a comparatively easy and cost efficient way.

List of reference numerals

1 cyclone dust separator unit

2 cyclone base unit

3 air guiding unit

4 cyclone head unit

5 cyclone element

6 cyclone funnel

7 air inlet

8 air guiding element

9 cover plate

10 duct

11 cap

12 outlet opening

13 air inlet section

14 air outlet section

15 cyclone type vacuum cleaner

16 ducting

Wl first welding

W2 second welding