EP2514347B1 - Vacuum cleaner turbo brush - Google Patents

Description

The present invention relates to a so-called vacuum cleaner turbo brush, so a vacuum cleaner mouthpiece with a driven by a turbine brush or bristle roller for a vacuum cleaner, in particular a vacuum cleaner in an embodiment as a vacuum cleaner, but also for so-called hand vacuum cleaner, wherein the turbo brush with a turbine (24 ) equipped in the secondary air flow and designed as a constant pressure turbine.

Turbo brushes are known per se and are used for example for cleaning carpets or the like and for sucking carpets with festgetretenem dirt in carpet pile. To the printed prior art can be so far on the DE 34 14 862 C2 are referenced, in which a vacuum cleaner mouthpiece with Saugrohranschluss, sliding sole and rotating brush roller is described. The brush roller is driven by a radially impinged turbine. Downstream of the turbine, a relatively narrow, movable nozzle is provided which concentrically directs the suction air or main air flow passing the nozzle to the impeller or turbine wheel. The turbine is a so-called resistance rotor. Because the turbine is operated in the main air flow, ie with dirty suction air, it can happen that absorbed dirt particles clog the intake duct with the guide nozzle or block the impeller. Such contamination must then be eliminated by the user of the turbo brush, which is basically possible without further ado, but is still perceived as a nuisance.

In addition to turbo brushes with turbines, which are driven by the suction air, turbo brushes are also known in which the turbines are driven as overpressure turbines in a secondary air flow with clean ambient air.

A disadvantage of the previous concepts is for a turbine in the main air flow especially a mostly reduced efficiency, which results from the fact that can not be used with the otherwise possible gaps between impeller and turbine housing due to the expected dirt particles in the air flow. In addition, the blade distances must be made comparatively large so that dirt particles can pass through the impeller. Known overpressure turbines, which are operated in the secondary air flow with clean ambient air, require the lowest possible gap between impeller and turbine housing to achieve sufficient efficiency. In addition, due to a significantly higher compared to the resistance rotor impeller speed (typically factor four), a complex conversion gear for transmitting the drive power to the brush roller is required.

A turbine of the type mentioned is from the GB 2 393 383 A known. There is proposed as a possible embodiment, a radially impinged turbine, but also a Peltonrad.

An object of the invention is to provide a further embodiment of a turbo brush, in particular an embodiment of a turbo brush with improved efficiency of the turbine used in the turbo brush.

This object is achieved with a vacuum cleaner turbo brush with the features of claim 1 or a vacuum cleaner with such a vacuum cleaner turbo brush. It is provided for the vacuum cleaner turbo brush that the turbine is arranged in the secondary air flow and designed as a constant pressure turbine.

The arrangement of the turbine in the secondary air duct and thus in the resulting secondary airflow during operation prevents dirt entry as it is unavoidable in an arrangement in the main air flow. When designed as a constant pressure turbine, the ambient air as the working medium before and after the impeller has the same static pressure. To drive the impeller, therefore, only the converted kinetic energy, the dynamic pressure, the sucked in ambient air is used. A constant-pressure turbine has a degree of reaction of zero, while overpressure turbines have a degree of reaction greater than zero.

The advantage of a constant pressure turbine is due to the lack of pressure difference before and after the impeller mainly in the possibility of less accurate sealing between the blades of the impeller and the turbine housing. This simplifies the production and allows production of the individual components with less stringent tolerances. Furthermore, a speed level of a constant pressure turbine with the same power output is about one-third below the speed level of a positive pressure turbine. This results either in a lower noise during operation or a possibility for Fertigungsyereinfachung over a positive pressure turbine, because less attention must be paid to noise-reducing measures or materials. This leads to a lighter and less expensive to manufacture turbine or a unit of turbine and a gearbox combined with it, because even for the gear initially results in the lower speed in a reduced noise. Finally, with the same mass flow and the same turbine diameter, a constant pressure turbine delivers twice as much power as a positive pressure turbine with a degree of reaction of 0.5.

The turbine is designed as an axial flowed impulse turbine. This allows simple conditions when fitting in a secondary air duct, through which the secondary air flow is sucked. The turbine housing can also round with its round outer contour Section of the secondary air duct are fitted so that edge-free or at least largely edge-free transitions between the secondary air duct and the turbine housing and further between the turbine housing and the upstream adjoining part of the secondary air duct are possible. In addition, unlike radial turbines, which require a rectangular or square inflow, even edge-free design of the air duct itself possible because, for example, no transitions between a square section for receiving the turbine and an adjoining possibly differently shaped section are required ,

In the case of the turbo brush, when a turbine shaft rotatably combined with an impeller of the turbine is surrounded by a shaft housing, in particular a one-piece shaft housing, the shaft housing acts as a turbulence-preventing or reducing guide element for the incoming ambient air and in the area of the turbine shaft in the region of a transition to the impeller Shroud of the turbine shaft and for receiving bearing elements for mounting the turbine shaft. If the shaft housing is widened in the region of the transition to the impeller to the entire diameter of the impeller and has openings for flow of the impeller, this part of the shaft housing also acts as a guide stage for the impeller. If such a baffle is part of the shaft housing, in particular integrally connected to the rest of the shaft housing, simple conditions for the production of the shaft housing and because of then possible edge-free transition favorable conditions for a laminar, turbulence-free or turbulenzenarme flow around the shaft housing and that of the Shrouding the turbine shaft via a guide element, which directs the incoming ambient air away from the arranged in the center of the secondary air duct turbine shaft and toward the blades of the impeller, to the Leitstufe.

Extensive investigations have shown that particularly favorable flow conditions and thus particularly good efficiency can be achieved if guide elements provided in the master stage and cones acting as turbine blades on the impeller have a specific geometry. Thereafter, a direction of flow in the first arc-shaped and then straight contour is provided for the guide elements formed in the leading stage in cross section. On the impeller are provided along its circumferential line evenly distributed, aerodynamically shaped pin, wherein the aerodynamic shape is characterized by a double-sided parabolic cross-sectional area.

Embodiments of the invention are the subject of the dependent claims. Relationships used here point to the further development of the subject-matter of the main claim by the features of the respective sub-claim.

In a particular embodiment, the vacuum cleaner turbo brush on a turbine downstream two-stage transmission, in particular in one embodiment as a belt transmission, for driving the bristle roller. The transmission allows a high speed of the bristle roller at a lower speed of the turbine than in a direct drive of the bristle roller. With a two-stage gearbox, the design-related, compared to an overpressure turbine lower speed of a constant pressure turbine can be compensated or more than compensated. A version as a belt transmission allows at the resulting speeds in operation, a substantial avoidance of running noise.

In a further embodiment it is provided that the vacuum cleaner turbo brush has a transmission housing surrounding the transmission with a turbine shaft opening and a driven belt opening and means for combination with the shaft housing. The transmission housing also encapsulates the transmission, so that in the secondary air flow or in the region of the secondary air flow, a significant proportion of the movable components, apart of course from the turbine wheel, are encapsulated, so that on the one hand dirt but on the other hand avoids turbulence and thus reducing the efficiency of the turbine reducing air turbulence or reduced.

In a particular embodiment, it is provided that, in the case of the cross-sectional area bounded on both sides by a parabola, the journal of the impeller is delimited by a narrower parabolic arc at a lower side surface in the direction of rotation by a further parabolic arc and an upper lateral surface in the direction of rotation. Such a geometry makes each pin an aerodynamic surface in the manner of a wing profile and thus improves the efficiency of the turbine.

When in the vacuum cleaner turbo brush with a housing and a main air and secondary air duct formed therein, the turbine is arranged in the secondary air duct and the main air duct are arranged centrally in the housing and the secondary air duct laterally adjacent to the main air duct, a concentration of the suction power is ensured on the main air duct. Only part of the suction power leads to the intake of ambient air via the secondary air duct.

This results in an optimum on the one hand high suction power over the main air duct and high turbine power to drive the bristle roller.

For a housing of the vacuum cleaner turbo brush comes into consideration that on the one hand a lower shell and connected to the lower shell walls of the main and Side air ducts, in particular with the lower shell integrally connected walls, and on the other hand, an intermediate shell for covering the main and secondary air duct in the lower shell. This leads to structurally simple conditions. The lower shell or the lower shell with channel walls integrally connected thereto can be produced in one production step, for example as an injection-molded part. The same applies to the intermediate shell. After attaching at least the turbine in the secondary air duct or in the region of an inflow region of the secondary air duct, the intermediate shell can be combined with the lower shell in a simple assembly step.

In a particular embodiment, the housing of the vacuum cleaner turbo brush has a cover shell, in which at least one supply air opening or supply air openings are formed for the turbine. By arranging the Zuluftöffnungen in the cover shell, so away from the surface to be sucked on the one hand prevents dirt particles are added to the secondary air stream, which can affect the operation of the turbine, and on the other hand, that when lifting the vacuum cleaner turbo brush does not cause any annoying howl from the ground due to the abrupt change in flow paths associated with liftoff.

If the Zuluftöffnungen are formed on both sides of the main air duct in the cover shell, in particular distributed symmetrically, results for the essential, visible during operation part of the housing an attractive appearance, wherein the supply air or a group of Zuluftöffnungen included in the design of the housing or its cover shell can be.

An embodiment of the invention will be explained in more detail with reference to the drawing. Corresponding objects or elements are provided in all figures with the same reference numerals.

The or each embodiment is not to be understood as limiting the invention. Rather, numerous modifications or modifications are possible within the scope of the present disclosure, in particular those which z. B. by combination or modification of individual, in connection with the described in the general description, the or each embodiment and the claims and features contained in the drawings or apparent from the process steps for the skilled in the art with a view to solving the problem and by combinable features lead to a new subject or to new process steps or process steps.

Fig. 1

eine Staubsauger-Turbobürste mit geöffnetem Gehäuse,

Fig. 2

eine Turbine der Staubsauger-Turbobürste in perspektivischer, teilweise geschnittener Darstellung,

Fig. 3

eine Explosionsdarstellung der Turbine aus Fig. 2,

Fig. 4

Details der Turbine als Schnitt durch deren Laufrad und eine vorgelagerte Leitstufe,

Fig. 5

die Staubsauger-Turbobürste aus Fig. 1 mit im Gehäuse angebrachter Zwischenschale und

Fig. 6

die Staubsauger-Turbobürste aus Fig. 1 oder Fig. 2 mit geschlossenem Gehäuse.

Show it

Fig. 1

a vacuum cleaner turbo brush with open housing,

Fig. 2

a turbine of the vacuum cleaner turbo brush in perspective, partially cut representation,

Fig. 3

an exploded view of the turbine Fig. 2 .

Fig. 4

Details of the turbine as a section through its impeller and an upstream Leitstufe,

Fig. 5

the vacuum cleaner turbo brush off Fig. 1 with mounted in the housing intermediate shell and

Fig. 6

the vacuum cleaner turbo brush off Fig. 1 or Fig. 2 with closed housing.

Fig. 1 shows a perspective view, however, schematically simplified a generally designated 10 vacuum cleaner turbo brush with the housing 12. The housing 12 includes a lower shell 14 and a visible only in the following figures intermediate shell 16 and cover shell 18th

In the housing 12, namely in the illustrated embodiment in the lower shell 14, a main air passage 20 and a secondary air passage 22 are formed. In the secondary air duct 22 and thus in there in the operation of the vacuum cleaner turbo brush 10 resulting secondary air flow, a turbine 24 is arranged, which is designed as an axial impinged equal pressure turbine. Downstream of the turbine 24 and driven by the turbine 24 is a transmission, in the illustrated embodiment a two-stage belt transmission 26. The belt transmission 26 is in turn provided in a conventional manner for driving a bristle roller 28 of the vacuum cleaner turbo brush 10. In the illustration, one recognizes the drive belt 30 provided for that purpose. In the illustration, the belt drive 26 is actually not recognizable, but only a transmission housing surrounding it. Here and below, the transmission and the transmission housing are designated by the same reference numeral 26. The transmission housing has a drive belt opening for exit of the drive belt 30 and a turbine shaft opening (not visible) for combination with the turbine 24.

The main air duct 20 is arranged centrally in the housing 12. The secondary air duct 22 is located laterally next to the main air duct 20. Main and secondary air duct 20, 22 open to a suction pipe 32, with the well-known manner, for example, not shown vacuum cleaner hose (suction) can be combined, so that the Vacuum cleaner fan (also not shown) generated suction air flow a main air flow through the main air passage 20 and a secondary air flow through the secondary air passage 22. The main and secondary air ducts 20, 22 are formed by walls 34 formed in the lower shell 14 or combinable with the lower shell 14. Fig. 2 shows more details of the turbine 24, related to their description and mention Fig. 1 was omitted for reasons of clarity. The turbine 24 is partially cut and shown in perspective. In the turbine 24 is an impinged axial impulse turbine, which is hereinafter referred to as turbine 24 for short. The turbine comprises, in a manner known per se, a turbine housing 36, an impeller 38 and a turbine shaft 40 connected in a rotationally fixed manner to the impeller 38. The turbine shaft 40 is surrounded by a bearing housing 42, which projects without edges from a section in the region of the shaft a side facing the impeller 38 widens and thus forms a transition 44. In the interior of the bearing housing 42 are bearing elements 46, so that turbine shaft 40 and bearing elements 46 are protected in operation from contamination. In addition, in this way the attachment of the turbine 24 in the lower shell 14 ( Fig. 1 ) of the housing 10 is facilitated. Such an attachment can namely be limited to the fact that the turbine 24 is used with its turbine housing 36 in a recess provided for this purpose and formed in the lower shell 14 in a secondary air duct 22, which fixes the turbine 24 in the flow direction. With the attachment of the intermediate shell 16 ( Fig. 5 ), the turbine 24 is locked in the auxiliary air duct 22 in total.

On the side facing away from the impeller 38, the bearing housing 42 has means for combining with a housing of the transmission 26, namely in the illustrated embodiment, a sealing region 48. The turbine shaft 40 ends on the side facing the gear 26 in a pulley 50. Here, the Gearbox 26 surrounding transmission housing (not visible in the illustrations) on a turbine shaft opening into which the pulley 50 protrudes. Next, the transmission housing has means for combination with the bearing housing 42, namely, for example, a seal which closes the turbine shaft opening together with the sealing region 48 of the bearing housing 42, in particular closes dust-tight.

On the side facing the impeller 38, behind the transition 44 to the bearing housing 42, the turbine housing 36 is integrally formed with a first part 51 of a baffle or combined with this releasably. A second part 52 of the master stage 53 is placed on the transition 44. Leitstufe 53 and impeller 38 are based on Fig. 4 explained in more detail. Shows before Fig. 3 nor a partially sectioned exploded view of the turbine according to Fig. 2 ,

Fig. 4 schematically shows a simplified section of a tangential section through the impeller 38 and the master stage 53. The upward-facing block arrow illustrates the resulting in operation flow direction with ambient air / secondary air. It can be seen that the guide stage has a plurality of guide surfaces 54 and the impeller a plurality of Turbine blades acting pin 56 has. Pins 56 and baffles 54 are, as better illustrated in FIG Fig. 2 or Fig. 3 can be seen evenly distributed over the circumference of the impeller 38 and der Leitstufe 53. The geometry of the guide surfaces 54 is such that they initially arc-shaped and then just forward the incoming ambient air to the impeller 38. The pins 56 are aerodynamically shaped, wherein the aerodynamic shape is characterized by a double-sided parabolic cross-sectional area. In the illustrated embodiment, the cross-sectional area of each pin 56 delimited on both sides is delimited by an upper side surface 58 and an adjoining lower side surface 60 in the direction of rotation (illustrated by the right-pointing, simple arrow). The upper side surface 58 forms a first parabolic arch. The lower side surface 60 forms a second parabolic arc differently shaped compared to the first parabolic arc, wherein the first parabola is narrower than the second parabola. In other words, the lower, second parabola is wider than the upper, first parabola. This geometry is one possibility for realizing a cross-sectional area of the pins 56, which makes them a total aerodynamically effective geometry in the manner of an airfoil.

Fig. 5 shows in the same perspective, the vacuum cleaner turbo brush 10 Fig. 1 , Unlike the in Fig. 1 shown situation, the intermediate shell 16 is now mounted in the lower shell 14. This closes with the walls 34 (in Fig. 5 not visible anymore; see. Fig. 1 ) the main and secondary air ducts 20, 22 (in Fig. 5 not visible anymore; see. Fig. 1 ) above. Furthermore, it can be seen that the drive belt 30 (in Fig. 5 not visible anymore; see. Fig. 1 ) is protected by a combined with the transmission housing cover. Of the turbine 24 are in the illustrated, installed in the secondary air duct 22 state nor the master stage 53 ( Fig. 2 ) and the turbine shaft 40 can be seen. Furthermore, it can be seen that the secondary air duct 22 widens in a funnel shape with its walls and the intermediate shell 16 and thus forms an inflow region for the turbine 24. With the intermediate shell 16 of the secondary air duct 22 is coupled to the inner volume of the housing 12, so that sucked as a secondary air into the housing 12 incoming ambient air.

Fig. 6 Finally, FIG. 1 shows a vacuum cleaner turbo brush 10 with a housing 12 closed with an attached cover shell 18. In the cover shell 18, supply air openings 62 are formed in the form of two symmetrically distributed groups of supply air openings 62. As already explained above, the secondary air duct 22 is coupled to the internal volume of the housing 12, so that ambient air for the secondary air flow is sucked in when the vacuum cleaner fan and the resulting suction air flow through the supply air openings 62.

In summary, some aspects of the proposed innovation can be as follows: It is a vacuum cleaner turbo brush for a vacuum cleaner, which has a turbine 24 for driving a bristle roller 28, the turbine 24 in a secondary air duct 22 and thus in operation in a secondary air flow arranged and designed as a constant pressure turbine, in particular as an axial impinged equal pressure turbine. Overall, the invention or embodiments thereof also relates to a vacuum cleaner with a vacuum cleaner turbo brush as described herein.

Claims (8)

1. Vacuum cleaner turbo-brush (10) comprising a turbine (24) in the secondary airstream, which turbine is designed as an impulse turbine,
   characterised by

   • it being designed as an axial-inflow impulse turbine,

   • it being equipped with a turbine shaft (40) which is non-rotatably combined with an impeller (36) of the turbine (24) and with a bearing housing (42) surrounding the turbine shaft (40), which bearing housing (42) serves as a transition (44) and/or a guide stage (51) in the region of the impeller (36) and as a casing for the turbine shaft (40) in the region of the turbine shaft (40), and serves to receive bearing elements (46) for supporting the turbine shaft (40),

   and

   • it being equipped with guide faces (54) which are formed in the guide stage (53) and are first arcuate and then straight in cross section in the inflow direction, and with aerodynamically formed journals (56) which are uniformly distributed on an impeller (38) of the turbine (24) over the circumferential line thereof, the aerodynamic shape being distinguished by a cross-sectional area delimited in a parabolic shape on both sides.
2. Vacuum cleaner turbo-brush according to claim 1, comprising a two-stage belt transmission (26) arranged downstream of the turbine (24).
3. Vacuum cleaner turbo-brush according to claim 2, comprising a transmission housing surrounding the transmission (26), which transmission housing comprises a turbine shaft opening and a drive belt opening and means for combining with the bearing housing (42).
4. Vacuum cleaner turbo-brush according to claim 3, wherein, for the cross-sectional area, which is delimited in a parabolic shape on both sides, of the journals (56) of the impeller (38), a side face (60) which is at the bottom in the direction of rotation is delimited by a wider parabolic curve and a side face (58) which is at the top in the direction of rotation is delimited by a narrower parabolic curve.
5. Vacuum cleaner turbo-brush according to any of the preceding claims, comprising a housing (12) and a primary air channel and a secondary air channel (20, 22) formed therein, the turbine (24) being arranged in the secondary air channel (22) and the primary air channel (20) being arranged centrally in the housing (12) and the secondary air channel (22) being arranged laterally next to the primary air channel (20).
6. Vacuum cleaner turbo-brush according to claim 5, comprising a lower shell (14) as part of the housing (12), comprising walls (34) of the primary and secondary air channels (20, 22), which walls are connected to the lower shell (14), and an intermediate shell (16) for covering the primary and secondary air channels (20, 22) in the lower shell (14).
7. Vacuum cleaner turbo-brush according to either claim 5 or claim 6, comprising a cover shell (18) as part of the housing (12) and comprising air inlet openings (62) formed therein for the turbine (24).
8. Vacuum cleaner turbo-brush according to claim 5, 6 or 7, comprising air inlet openings (62) formed in the cover shell (18) on both sides of the primary air channel (20).

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