Field of the invention

[0001] The invention relates to domestic vacuum cleaners, comprising steam cleaning functionality. In particular, the invention relates to a canister steam and vacuum cleaner which is small and handy, being easy to carry and store, having at least one of width, length and height of the main body which is equal to or less than 300 mm, preferably equal to or less than 280 mm, more preferably equal to or less than 270 mm.

Background of the invention

[0002] It is very advantageous, when performing deep and complete cleaning of domestic surfaces (such as floors, windows, mattresses, walls, etc.), to employ a cleaner with multiple functions. In particular, a steam and vacuum cleaner, i.e. a vacuum cleaner capable of drawing and filtering dirt and dust, while providing steam for removing dirt and grime embedded on the surfaces, is highly desirable. The use of high temperature steam results in fact in deeper and more hygienic cleaning.

[0003] However, conventional steam and vacuum cleaners have the main drawback of being bulky and unhandy.

[0004] Some apparatuses, such as upright vacuum cleaners, although having reduced width, are too heavy to lift, being suitable at most for cleaning floors, but not vertical surfaces, such as windows and walls. As an example, US 2009/100631 discloses an upright vacuum cleaner with steam functionality, wherein the brush contains the vacuum means; said apparatus is thus only suitable for cleaning floors, while it is unhandy for cleaning vertical surfaces. The same applies to the upright steam and vacuum cleaner disclosed in WO 2013/044196, which furthermore requires the inconvenient substitution of two different heads for using it alternatively in vacuum or steam cleaner configuration.

[0005] Much handier than upright vacuum cleaners are canister vacuum cleaners. The basic design of a canister vacuum cleaner comprises a long, flexible hose and a separated main body which houses the motor and the separation system . However, the canister vacuum cleaners currently on market, having also a steam supply section, are very bulky. [0006] As an example, the present Applicant currently commercializes a canister steam and vacuum cleaner having size (L x W x H) of 49 x 32 x 33 cm.

[0007] Also US 3896521 discloses a large apparatus for wet and dry vacuum cleaning, with a steam cleaning function, whose size is 50,8 x 45,7 x 35,6 cm.

[0008] US 2004/111822 discloses a bulky vacuum cleaner which can be further supplied with a separated steam generator: the overall size of the apparatus, including vacuum and steam cleaning means, is thus very big .

[0009] EP 1818001 discloses a vacuum cleaner with steam generator, wherein the steam generator is located inside the brush. This configuration requires the brush to have suitable size for storing the water to be boiled; consequently, the apparatus is unhandy.

[0010] Because of their size and/or poor maneuverability, the steam and vacuum cleaners of the prior art are considered unsuitable for daily cleaning. Consumers, who would seldom employ the steam function, e.g. only when a deep cleaning work is required, preferably purchase "pure" vacuum cleaners, to be used for removing dust. However, this is more time consuming as it requires to wipe surfaces with a dump cloth afterwards.

[0011] On the other hand, smaller machines, such as portable vacuum cleaners with steam functionality, as the one described in EP 0586762, have the drawback of having low vacuum power, being only suitable for cleaning small surfaces.

[0012] A further problem faced with domestic steam and vacuum cleaners is the difficulty of using said machines for cleaning the house stairs. In fact, while compact vacuum cleaners, having size compatible with stair steps, are provided, compact vacuum cleaners having also a steam functionality are not available. Current steam and vacuum cleaners are in fact generally bigger than "pure" vacuum cleaners, consequently the placement of the body of a steam and vacuum apparatus is constrained on the top or bottom of the stair or at most on the intermediate landing, making it possible to vacuum clean only the proximate steps.

[0013] In any case, the marketability of the currently available devices, providing both vacuum and steam cleaning functionality, is minor.

[0014] The drawbacks of the prior art' s devices have been overcome by the present invention, which provides an apparatus for steam and vacuum cleaning, which has high vacuum power and efficient steam generation, which is as handy and compact as conventional canister vacuum cleaners and which is thus suitable for use on a daily basis.

Summary of the invention

[0015] The present invention relates to a canister steam and vacuum cleaner, particularly for domestic use, which combines very high cleaning efficiency with small size. In particular, the present invention relates to a canister steam and vacuum cleaner, which is compact in size and whose main body has at least one dimension compatible with the tread depth of a stair step, i.e. whose main body has height, length and width dimensions, wherein at least one of said dimensions is equal to or less than 300 mm, preferably equal to or less than 280 mm, more preferably equal to or less than 270 mm.

[0016] The canister steam and vacuum cleaner of the present invention has the advantage of being a high power vacuum cleaner having also steam cleaning functionality, still being very small and easy to handle. Preferably, the canister steam and vacuum cleaner of the invention has a total power ranging from 700 W to 3000 W.

[0017] In particular, the canister steam and vacuum cleaner of the invention, having such a compact size, is very advantageous as it can be easily carried during the house cleaning, being thus suitable for daily domestic use.

[0018] Furthermore, it is possible to use the canister steam and vacuum cleaner of the invention for cleaning house stairs, as it can stand on a stair step.

[0019] Said features are not comprised in the steam and vacuum cleaners of the prior art.

[0020] Preferably, the steam generation means and the vacuum and filtering means of the canister steam and vacuum cleaner of the invention are located side-by-side, along a longitudinal direction, extending from the front to the rear side of the vacuum cleaner's body. More preferably, the vacuum and filtering means are located in a frontal portion of the main body, while the steam generation and supply means are located in a rear portion of the body, or vice versa.

[0021] Preferably, the fan and the engine of the canister steam and vacuum cleaner of the invention are located over the vacuum and filtering means, along a longitudinal axis, extending from the base to the top of the vacuum cleaner's body. Brief description of figures

[0022] Figure 1 : perspective view of a preferred embodiment of the apparatus of the invention .

[0023] Figure 2: side view of the apparatus of figure 1.

[0024] Figure 3: perspective view of the apparatus of figure 1, wherein the front case has been removed, as to show the vacuum and filtering means (2) of the apparatus. The walls of the dust-collection bucket (3) are marked with broken lines in order to make the inside visible.

[0025] Figure 4: plan view in vertical section of the vacuum and filtering means of the apparatus of figure 1, comprising the dust-collection bucket (3).

[0026] Figure 5 : plan view in horizontal section of the vacuum and filtering means of figure 4 in correspondence of the second cyclones.

[0027] Figure 6: perspective view partially exploded of the vacuum and filtering means of the apparatus of figure 1.

[0028] Figure 7: plan view in vertical section of the vacuum and filtering means according to a preferred embodiment of the invention .

[0029] Figure 8: plan view in horizontal section of the vacuum and filtering means of figure 7 in correspondence of the toroidal partition wall.

[0030] Figure 9 : perspective view of the apparatus of figure 1, wherein the posterior case has been removed, as to show the steam generation means (30) of the apparatus. Detailed description of the invention

[0031] The present invention is directed to a canister steam and vacuum cleaner, comprising a main body, within which vacuum and filtering means are located together with means for steam generation and supply, and wherein said body has height, width and length dimensions such that at least one of said dimensions is equal to or less than 300 mm, preferably equal to or less than 280 mm, more preferably equal to or less than 270 mm.

[0032] The size of the main body of the canister steam and vacuum cleaner of the present invention is such that said main body can stand on the tread depth of a stair step.

[0033] Preferably, said main body has width comprised between 200 and 300 mm, more preferably between 240 and 280 mm, length comprised between 400 and 600 mm, and height comprised between 350 mm and 550 mm. [0034] Preferably, the canister steam and vacuum cleaner of the invention comprises a main body whose dimensions are such that it can be stored in a cabinet of standard dimensions, when not used, for example in a cabinet having height of about 500 mm, width of about 300 mm and length of about than 550 mm.

[0035] Preferably, the canister steam and vacuum cleaner of the present invention has a total power of from 700 W to 3000 W.

[0036] Preferably, the vacuum and filtering means of the canister steam and vacuum cleaner of the invention are located in the main body together with the steam generation means, along a longitudinal axis extending from the front to the rear portion of the main body. More preferably, the vacuum and filtering means are located in a frontal portion of the main body, while the steam generation means are located in a rear portion of the main body.

[0037] The vacuum and filtering means preferably comprise one or more filtering section (s).

[0038] In a preferred embodiment, the one or more filtering section(s) comprise a water filtration system. Water filtration systems are bagless filtration systems, characterized in that the suctioned dirt remains trapped in a fluid, preferably water, which is contained in the filtering section(s).

[0039] In a further preferred embodiment, the one or more filtering section(s) comprise one or more cyclonic unit(s).

[0040] Preferably, the vacuum and filtering means comprise a fan, actioned by an electric engine, providing the suctioned air flow; more preferably said engine and fan are located over the one or more filtering section(s) along a longitudinal axis extending upwards.

[0041] The assembly of the vacuum and filtering means along a longitudinal axis extending upwards favors the reduction of the body size and in particular of the body width, compared to conventional steam and vacuum cleaners.

[0042] Typically, canister vacuum cleaners comprise a hose, through which air is suctioned, connected to the main body by means of a hose inlet.

[0043] According to a preferred embodiment of the invention, a hose inlet is located on a rear portion of the main body.

[0044] A handle is also preferably present on the top of the main body, optionally a telescopic handle with variable height, which allows to push forward the main body of the vacuum cleaner while cleaning after, instead of dragging the main body by pulling the hose as the surface is cleaned, as it is typically done with conventional canister vacuum cleaners.

[0045] The design of the present invention comprising the hose inlet in the rear portion and the handle on top of the main body, according to a preferred embodiment, is particularly advantageous when using the steam function. In fact, when supplying steam, e.g. on the floor, said steam condense; therefore, dragging the body of the device, this would pass over the wet surfaces dirtying them again. As a consequence, either the device has to be complicatedly maneuvered or a certain time has to be waited for the floor to dry. These preferred features avoid said drawback, as the main body can be easily pushed forward, leaving behind the wet surface.

[0046] According to a preferred embodiment, the one or more filtering section(s) comprise a first cyclonic unit which is delimited by an outer wall and an inner wall, wherein the radial distance between said outer wall and said inner wall is comprised between 20 mm and 40 mm, preferably between 25 mm and 35 mm. Said distance, which is wider than the typical distance between the inner and outer walls of conventional cyclonic units, allows to efficiently separate both solids and liquids, still maintaining efficient and satisfactory cyclonic movement of air.

[0047] Preferably, the one or more filtering section(s) further comprise a collection chamber for collecting solids and /or liquids separated in the cyclonic unit(s) . Said collection chamber is preferably located below the first cyclonic unit, partially separated from that by a toroidal partition wall.

[0048] Said toroidal partition wall preferably extends radially from an inner portion of the filtering sections toward a side wall, without contacting it. An annular space is thus identified between the perimeter of the toroidal partition wall and said side wall, which annular space puts in fluid communication the collection chamber and the cyclonic unit, allowing the liquids and/or solids, which have been separated from the suctioned air flow, to fall into the collection chamber.

[0049] Preferably, the radial distance between the perimeter of the toroidal partition wall and the side wall is of from 1 mm to 9 mm, more preferably of from 1.5 mm and 8 mm. Said radial distance can provide efficient fall of separated solids and liquids into the collection chamber, with substantially no deposition of dirt over the partition wall. Furthermore, it avoids the backflow of liquids separated in the first cyclonic unit. [0050] Preferably, the collection chamber further comprises a vertical radial baffle, which prevents the formation in the collection chamber of rotating flows of air and liquids which could cause the liquids to flow over the toroidal partition wall, outside the collection chamber.

[0051] Preferably, the collection chamber is designed to collect at least 200 cm ³ , more preferably at least 400 cm ³ , most preferably at least 600 cm ³ , of liquids.

[0052] According to a more preferred embodiment, the perimeter of the toroidal partition wall comprises an indent, so that the portion of the toroidal partition wall comprising the indent is more distal to the side wall, compared to the rest of the perimeter of the toroidal partition wall. Preferably, the portion of the toroidal partition wall comprising the indent extends for about one third of the perimeter of said toroidal partition wall.

[0053] Preferably, the radial distance between the perimeter of the partition wall and the side wall, measured at the level of the indent of the toroidal partition wall, measures from 6 mm to 9 mm, preferably from 7 mm to 8 mm, while the shortest radial distance, measured at the more proximal edge of the toroidal partition wall, measures from 1 mm to 3 mm.

[0054] Preferably, the one or more filtering section(s) comprise a dust collection bucket. More preferably, the bottom of the dust collection bucket is shaped so as to define the collection chamber for collecting liquids and/or solids separated from the suctioned air flow.

[0055] The toroidal partition wall, which, according to a preferred embodiment, partially separates the collection chamber from the first cyclonic unit, more preferably radially extends toward the side wall of the dust collection bucket.

[0056] Preferably, the toroidal partition wall extends parallel to the bottom of the dust-collection bucket, more preferably at a height of from 35 to 85 mm from the bottom of the dust-collection bucket, most preferably at a height of from 40 to 70 mm from the bottom of the dust-collection bucket.

[0057] Preferably, the outer wall of the first cyclonic unit is the side wall of the dust collection bucket, said side wall comprising a tangential inlet for entry of suctioned air.

[0058] Preferably, the one or more filtering section(s) further comprise a filter element, having an outer wall provided with a plurality of lateral openings. More preferably, said filter element has a truncated conical shape, tapering downwardly. [0059] According to a more preferred embodiment, the filter element is contained in the dust-collection bucket, substantially concentric to the side wall of the dust-collection bucket itself, so that an annular chamber is defined between the side wall of the dust collection bucket and the outer wall of the filter element, said annular chamber corresponding to the first cyclonic unit.

[0060] The upper part of the dust-collection bucket is preferably closed by an annular lid, which hermetically closes the dust-collection bucket around the outlet.

[0061] Preferably, the one or more filtering section(s) further comprise at least one second cyclonic unit, positioned downstream of the first cyclonic unit, along the aforesaid path for filtration of solids and/or liquids.

[0062] In a preferred embodiment, the at least one second cyclonic unit is located in an upper portion of the dust-collection bucket.

[0063] Alternatively, the at least one second cyclonic unit can be positioned over the dust collection bucket, along the prosecution of its longitudinal axis.

[0064] In a preferred embodiment, the at least one second cyclonic separation stage projects at least partially into the first cyclonic unit.

[0065] In another embodiment, the second cyclonic separation stage does not extend into the first cyclonic unit.

[0066] In a preferred embodiment, the second cyclonic unit includes a drain connected to a conduit for the collection of finest particles. More preferably, said conduit for the collection of finest particle is located at the bottom of the dust-collection bucket, in a portion of the same substantially concentric to the side-wall of the dust-collection bucket.

[0067] Preferably, the second cyclonic unit includes a plurality of second cyclonic separators arranged in parallel. Each second cyclonic separator is preferably individually fed in parallel to the others from an upper portion of the first cyclonic unit. Each second cyclonic separator preferably includes an upper cylindrical portion, provided with an inlet in communication with the aforesaid upper portion of the first cyclonic unit, and a lower frustoconical portion tapering downwards, with an outlet provided at the lower end of the frustoconical portion and pointing towards the conduit for the collection of finest particles. [0068] Preferably, the drain leading to the conduit for the collection of finest particle extends at least in part along a portion of the filter element, substantially concentric to the outer wall of the filter element.

[0069] In further embodiments, the vacuum and filtering means comprise more than two cyclonic separation stages; examples of filtering sections comprising more than two separation stages are disclosed in EP1898768, US2011061351, EP1883336.

[0070] Preferably, the main body comprises wheels for the vacuum cleaner's movement.

[0071] Preferably, a protective case covers a major portion of the body.

[0072] In a preferred embodiment, the canister steam and vacuum cleaner comprises a power cord, which must be connected to an electric plug in order to operate the electric engine. More preferably, the power cord is retractable, being wounded in coil inside the main body of the vacuum cleaner when the apparatus is not operated. In the aim of mostly reducing the space amount of the vacuum cleaner of the present invention, when the power cord is coiled inside the main body, it is preferably located in a portion of the main body which is on a horizontal plane, parallel to the bottom of the main body.

[0073] Preferred embodiments of the present invention will be now described in more details with reference to the drawings.

[0074] Figures 1 and 2, show preferred embodiments of the canister steam and vacuum cleaner of the present invention, wherein the vacuum and filtering means (2) are located in a frontal portion of the main body ( 1). Said preferred embodiment is shown in figure 9 as well, wherein the rear case of the canister steam and vacuum cleaner has been removed in order to show the steam generation and supply means (30) located in a rear portion of the main body ( 1).

[0075] The hose inlet (31) is shown in figure 1 located in the rear portion of the main body, according to a preferred embodiment of the invention. The hose inlet is in fluid communication with the inlet (4) of the cyclonic separation system, as shown in figure 9.

[0076] According to a preferred embodiment, as shown in figure 3, the fan ( 10) and the electric engine ( 11) operating the fan are located above the one or more filtering section(s) (32), more preferably above the dust-collection bucket (3), along a longitudinal axis extending upwards. [0077] A preferred embodiment of the one or more filtering section(s) (32) is shown in Figure 6, with a partially exploded perspective view. The filtering sections (32) are shown at least partially inserted inside a dust-collection bucket (3), along the prosecution of the longitudinal axis of the latter, substantially concentric to it. A tangential air inlet (4), feeding the first cyclonic unit is present in correspondence of a median portion of the dust-collection bucket. The filtering sections (32) comprise a filter element ( 12), whose wall comprises a plurality of lateral filtering openings (13), through which the suctioned air flows. The filter element ( 12) preferably has a frustoconical shape and is contained inside the dust-collection bucket (3), substantially concentric to the side wall of the same, so that the interspace between the wall of the filtering element and the side wall of the dust-collection bucket defines the first cyclonic unit ( 14) . Said preferred embodiment is also shown in vertical section in figures 4 and 7.

[0078] As shown in figures 4 and 7, the bottom of the dust-collection bucket (3) is preferably shaped as to form an annular relief (6) which defines an annular collection chamber (7), for the collection of liquids and/or solids separated by the first cyclonic unit, and a central portion (8) for the collection of finer particulate, which has been separated by the second cyclonic unit. The aforesaid annular chamber (7) preferably comprises a vertical radial baffle (9).

[0079] The first cyclonic unit (14) is preferably positioned above the collection chamber (7), and partially separated from that by a toroidal partition wall (15), which extends radially from a central portion of the dust collection bucket (3) toward the side wall of it.

[0080] As shown in figure 8, according to a preferred embodiment, an open passage (28) is left between the perimeter of the radial partition wall (15) and the side wall of said dust-collection bucket (3), through which suctioned liquids or heavier solids precipitate by gravity from the first cyclonic unit (14) to the collection chamber (7). Said partition wall ( 15) can have uniform radial distance to the side wall or can comprise an indent (29), so that a portion of said partition wall (15) is more distant to the side wall.

[0081] The dust-collection bucket (3) is preferably closed at the top by an annular cover (26), which tightly closes the collection bucket (3) around the expulsion outlet (5), by interposition of sealing means (27).

[0082] According to a preferred embodiment, as shown in figures 4-7, a second cyclonic unit is further present, composed of a plurality of cyclone separators ( 19) arranged in parallel. Said second cyclone separators (19) are connected to the drain ( 18), which conveys the finer particles separated from the air flow into a collection conduit (8). Each second cyclone separator ( 19) is fed in parallel to the other second cyclones separators from an upper portion (20) of the filtering path, preferably formed by the annular interspace identified between the filter element ( 12) and the conduit of decantation (18). Each second cyclone separator (19) includes an upper cylindrical portion (22), provided with an inlet in communication with the aforesaid upper portion (20), joined to a lower frustoconical portion (23) tapering downwards, provided with an outlet at the lower free end of the frustoconical portion, pointing towards the conduit for the collection of finest particles ( 18) . Each second cyclone separator ( 19) preferably comprises a cylindrical duct (24), concentric to the cylindrical portion (22) of the cyclone separator, through which the filtered air is discharged to the opening (5) of the collection bucket, preferably with interposition of a filter (21).

[0083] With reference to the preferred embodiments described above and shown in the drawings, it is worth noting that a dual-stage cyclonic separation, together with a filter element, is capable of separating with high efficiency both solids and liquids from the aspirated air stream. With the first cyclonic stage, liquids and heavier particles are precipitated into the outer annular collection chamber (7). The outgoing air from the first cyclonic stage, still containing finer particles, is conveyed, through the holes ( 13) of the filter element (12) and the annular gap identified between the filter element (12) and the decantation conduit (18), to an upper portion of the first cyclonic separation stage (20). The air is thus conveyed upwards, entering the second cyclone separator stage ( 19), due to the suction flow. Once purified, exhausted air is expelled through the outlet (5), preferably after being transited through a further filter (21).

[0084] The assembly of the elements of the canister steam and vacuum cleaner of the invention, according to the preferred embodiments herein described, cooperate in reducing the size of the vacuum cleaner of the present invention.