EP2537450A1 - Dust trap - Google Patents

Abstract

The device has a nozzle (4) comprising a nozzle hole head (8), and a nozzle outlet (10) for conducting air from the nozzle head to the nozzle outlet in a flow direction. A dust housing (6) is connected directly to the nozzle outlet in the flow direction, and has an inlet funnel (12) projecting from the nozzle outlet till to a dust chamber opening (14), where the funnel is attached to the outlet. The funnel is arranged in an inner side of a dust container (16) of the housing such that a dust-receiving volume is formed between an outer wall of the funnel and an inner wall of the container.

Description

TECHNICAL AREA

Embodiments of the invention are concerned with dust collection devices for a vacuum cleaner, and more particularly with the new concepts for such dust collection devices.

STATE OF THE ART

Vacuum cleaners and hand vacuum cleaners exist in great variety and variety of shapes on the market. Vacuum cleaners typically have a vacuum cleaner nozzle with a nozzle mouth for sucking in dirt particles or air, as well as a dust housing, within which different dust retention components, such as filter bags, are arranged.

To increase the suction power of the vacuum cleaner, the power of a fan of the vacuum cleaner driving electric motor is typically increased, but this leads to undesirably higher energy costs. Especially with hand vacuum cleaners, which are often battery operated, such an increase in suction power can lead to a reduced suction time of the device, which can adversely affect the applicability of a hand vacuum generally.

Thus, there is a need to search for alternative ways to increase the suction power of a vacuum cleaner

PRESENTATION OF THE INVENTION

In some embodiments of the present invention, flow optimization of the nozzle and a dust housing adjacent thereto is undertaken. Thus, some embodiments of the invention have a nozzle with a nozzle mouth and a nozzle outlet, which is immediately followed by a dust housing, which has an inlet funnel adjacent to the nozzle exit and tapering from the nozzle exit to a dust space opening. The nozzle exit is thus coupled directly to a tapered inlet funnel in the dust space or the dust housing, so that a maximum cross section at the interface or a connection point between the nozzle and the dust housing can be used, which in turn can significantly reduce the flow resistance. At the same time in some embodiments by means of the tapered inlet funnel can still be achieved in a streamlined manner, a direct or indirect flow of a filter element.

In some embodiments, the cross section at the nozzle exit is at least greater than 70% of a cross section of the nozzle at the nozzle mouth, ie a cross section of the nozzle at the point at which the polluted air is sucked by means of the nozzle. In further embodiments, the cross section at the nozzle exit is even larger than the cross section of the nozzle at the nozzle mouth. This can help minimize flow losses. In further embodiments, the air-guiding cross-section of the nozzle at any point between the nozzle mouth and the nozzle exit does not decrease to less than 70% or 100% of the cross section of the nozzle at the nozzle mouth.

In some embodiments, the inlet hopper has the shape of a truncated cone to achieve a uniform, streamlined reduction in cross-section.

In some embodiments, located within the dust housing is a dust container or a dust container forming arrangement, wherein the inlet funnel is disposed within and surrounded by the dust container so that a dust-receiving volume is formed between an outer wall of the inlet funnel and an inner wall of the dust container. Due to the combination of the tapered inlet funnel and the surrounding dust container, a dust trap is formed into which the coarse dirt entering the housing can enter and from which the coarse dirt can no longer escape during normal operation.

In some embodiments, the inlet hopper and the dust container are in shape formed concentric truncated cones, so that a flow-favorable and efficient operation of the dust trap and the dust container can be ensured, since it surrounds the inlet funnel completely and with a uniform opening cross-section.

In some embodiments, the dust collection device further includes a baffle that extends in the dust container toward the dust space opening and can redirect the airflow into the dust bin in a streamlined and energy efficient manner. In some embodiments, the baffle has the shape of a cone or a rounded surface or surface to provide the deflection in a streamlined and energy efficient manner.

In some embodiments, the side of the dust container facing the inlet funnel can additionally be provided with a filter element in order to retain fine dust particles in the dust-receiving volume or in the dust space. In some other embodiments, the dust container for this purpose on a plurality of projections which extend into the dust-receiving volume and which are suitable for receiving a filter element, so that due to the elevations a uniform flow of the filter element from the back, ie from the side , of which a negative pressure to achieve the suction force, can be achieved. In some embodiments, these elevations are designed in the form of narrow, parallel to a flow direction of the air extending ribs. This can result in a smooth backflow without significantly increasing the total drag through the airway obstructing elements.

For aspirating the cleaned air, the dust container further comprises, in some embodiments, a plurality of flow openings to the dust container closely enclosing dust housing, so that acting in the dust housing vacuum can serve to suck air through the flow openings. In this case, the dust container may have a plurality of flow openings, each defining a possible flow path of the air, wherein different of these flow paths may be different lengths. That is, the air molecules travel different distances along different flow paths. In some embodiments, the cross section of the flow openings varies such that it is larger for longer flow paths than for shorter flow paths. This can cause a suction power or a suction force of a vacuum cleaner equipped with such a dust catching device to remain constant during operation, even if, for example, a filter element successively becomes so clogged that initially the shorter flow paths are interrupted by the added filter. In other words, the use of longer filter passages caused by the addition of the filter, which could possibly lead to increased flow resistance, is compensated by flow openings of larger cross-section, so that overall a high suction constancy can be achieved.

In further embodiments, an opening cross-section of the nozzle outlet is dimensioned and geometrically designed so that the entire surface of a filter is uniformly flowed, which can lead to a uniform clogging of the filter and too long Saugkraftkonstanz.

In further exemplary embodiments, the nozzle is configured from the nozzle orifice to the nozzle outlet or has such an internal cross-section that the flow direction of the air announced by the nozzle at the nozzle outlet is substantially tangential to an inner wall of the inlet funnel. This may, in some embodiments, cause the flow to flow with less turbulence along the inlet funnel and up to an outlet opening of the dust housing. Reducing areas of turbulent flow increases efficiency as their design would reduce the effective flow area of airflow. This can significantly reduce the flow resistance, which can also contribute to further reducing the required engine power.

In further embodiments, the cross-section of the nozzle at the nozzle outlet is elliptical or circular, so that in flow-favorable manner, a maximum cross section for the transition from the nozzle to the dust housing can be used. In some of these embodiments, a diameter or extension of the large semiaxis of the cross section is at least so large that the cross section of the nozzle at the nozzle exit exceeds 70% or 100% of the cross section of the nozzle at the nozzle mouth. For example, these dimensions may be greater than 8, 10, 13, 20, 25, or 30cm.

In some of these embodiments, the inlet funnel at the dust chamber opening, ie at its end facing the storage space or at the transition to the dust housing, a pinhole, by means of which coarse dirt can be reliably retained. In other of these embodiments is located at this point a downwardly bulging chicane or a dust trap that can prevent falling back of the material to be sucked into the nozzle.

In some embodiments, the dust housing tapers funnel-shaped on an opposite side of the dust chamber opening to an air outlet to which, for example, a motor or a fan can be connected, wherein the funnel-shaped taper can contribute to a further reduction of the flow resistance.

In some embodiments, a receptacle for a filter cartridge is further provided between the dust chamber opening and the air outlet into which, for example, pleated or flat filter material can be introduced.

BRIEF DESCRIPTION OF THE FIGURES

• Fig. 1 ein Ausführungsbeispiel einer Staubfangvorrichtung in einer perspektivischen Schnittansicht;
• Fig. 2 eine zweidimensionale Schnittansicht des Ausführungsbeispiels von Fig. 1;
• Fig. 3 ein Ausführungsbeispiel einer Staubfangvorrichtung mit zusätzlichem Motorschutzfilter;
• Fig. 4 ein weiteres Ausführungsbeispiel einer Staubfangvorrichtung in einer perspektivischen Schnittansicht; und
• Fig. 5 eine alternative Darstellung des Ausführungsbeispiels von Fig. 4.

Some embodiments of the invention are explained in more detail below, with reference to the attached figures. Show it:

• Fig. 1 an embodiment of a dust collecting device in a perspective sectional view;
• Fig. 2 a two-dimensional sectional view of the embodiment of Fig. 1 ;
• Fig. 3 an embodiment of a dust collector with additional motor protection filter;
• Fig. 4 a further embodiment of a dust collecting device in a perspective sectional view; and
• Fig. 5 an alternative representation of the embodiment of Fig. 4 ,

DETAILED DESCRIPTION OF EMBODIMENTS

The Figures 1 and 2 show an embodiment of a dust collecting device for a vacuum cleaner or for a handheld vacuum cleaner in a mounted on a fan assembly 2 state. For the sake of clarity, a more detailed description of the fan assembly 2 will be omitted below, the exact embodiment with respect to the dust collection device is not essential.

The dust collecting device comprises a nozzle 4 and a dust housing 6. The dust housing 6 may be formed in one piece or in several parts and consist of several functional units or components, which will be explained in more detail below. The nozzle 4 has a nozzle mouth 8, which in the present case has a rectangular cross-section, and a nozzle outlet 10, on which the nozzle 4 directly adjoins the dust housing 6 or an inlet funnel 12 located in the dust housing 6. At the in FIG. 1 In the embodiment shown, the nozzle outlet 10 has a circular cross-section in order to allow a flow-efficient transition to the inlet funnel 12. Although the cross section of the nozzle mouth 8 in FIG. 1 is rectangular, of course, any other cross section are possible, for example, trapezoidal, round or elliptical.

The inlet funnel 12 is frusto-conical and tapers in the shape of a cone from the nozzle exit to a dust chamber opening 14, at which the inlet funnel 12 ends, so that the guided through the inlet funnel 12 air can pass at the dust space opening 14 in a dust-receiving volume. The dust-receiving volume is formed between an outside of the inlet hopper 12 and an inside wall of a dust container 16. The dust container 16 in turn is part of the dust housing 6 and in the present case designed in one piece with the dust housing 6. In alternative embodiments, the individual in FIG. 1 Of course, components that are illustrated can also be designed in several parts. The dust housing 6 is also frusto-conical and arranged concentrically to the inlet funnel 12 and has a A plurality of flow openings 18a to 18f, can flow through the aspirated air from the dust container 16 in the dust housing 6 and in the volume between dust housing 6 and dust container 16, from where it can pass through an air outlet 20 to the blower assembly 2.

By doing FIG. 1 In the embodiment shown, the air emerging from the dust space opening 14 is deflected by means of a cone-shaped deflecting body 22 in order to reach the dust-receiving volume between the inlet funnel 12 and the dust container 16. This shape of the deflector 22 promotes a streamlined deflection of the air. In order to be able to remove particulate matter from the air in addition to the coarse dirt, this is shown in FIG. 1 illustrated embodiment further includes optional filter 24 which is disposed on an inner wall of the dust container 16. In particular, the dust container 16 for this purpose has a plurality of extending into the dust-receiving volume elevations or webs 26, which allow a uniform flow against the filter or a uniform flow behind the filter 24. Although in this case the baffle 22 is shown as part of the filter, this may be formed in alternative embodiments, part of the dust container 16 or as a separate element. The webs 26 extend parallel to the flow path or to the flow direction of the air in order not to unnecessarily increase the flow resistance of the arrangement.

In further embodiments, the in FIG. 1 Of course, shown webs 26 and surveys have other geometries, to allow a uniform backflow.

As in FIG. 1 1, a cross section of the flow openings 18a to 18f increases with the length of the flow path belonging to the individual flow openings (the path leading from the dust space opening 14 to the air outlet 20 via the relevant flow opening) in order to be able to ensure a suction force that is as constant as possible over the operating period.

At another, in FIG. 1 not shown embodiment of the nozzle 4, the inner cross section of the nozzle is designed such that the air is rotated so that it tangential or approximately tangential to the surface of the inlet funnel 12 in the inlet hopper 12 and substantially in the form of a spiral flows to the dust chamber opening 14, which can further reduce the flow resistance. In further embodiments, a filter may be arranged directly on the inner walls of the inlet funnel 12 for this purpose.

In other words, they show Figures 1 and 2 a dust collecting device in which a long funnel-shaped channel leads from a nozzle far into the dust chamber. The filter bag with large inlet opening is formed around the inlet funnel. The dust cone is designed double-walled and equipped with enlarging to the flow end hole openings as a motor protection filter to ensure the longest possible suction constancy even at high dust load. Between filter and dust cone, ribs are attached, which ensure a uniform back flow of the filter.

A deflector cone directly behind the inlet opening in the dust chamber directs the air flow to the outside, thus avoiding the falling back of the dirt in the nozzle area. In further embodiments, additionally or alternatively, a closure cap, for example in the form of a ball with a through hole, prevent falling out of dirt. This may, according to some embodiments automatically close and open when the device is turned on or when a negative pressure is applied to the input of the dust container. Behind the perforated screen or behind the dust container with the flow openings, the flow is deflected and passed in a slowly tapering funnel to the blower opening 20.

In other embodiments with different nozzle geometry, a suction channel within the nozzle gradually tapers and twists to a tangential entrance into the dust space. The flow can thus run in a uniform spiral along the filter bag wall and turn at the end funnel-shaped into a fan opening.

FIG. 3 shows a further embodiment of a dust collecting device, which in large parts the reference to the Figures 1 and 2 corresponds to described embodiment. A renewed description of the similarities is therefore omitted below.

The embodiment of FIG. 3 additionally has a motor protection filter 25, which is arranged in the flow path of the air in front of the air outlet 20 to a tearing the filter 24 to protect the motor of the fan assembly 2 from damage by larger dirt particles that could pass through the flow openings 18a to 18f to the engine.

The FIGS. 4 and 5 show a further embodiment of dust collection devices in a mounted on a fan assembly 2 state.

Since the basic geometries of the nozzle 4 and the inlet funnel 12 immediately after the nozzle 4 from the previously with reference to the Figures 1 and 2 discussed embodiments differ little, is below only briefly to the differences or deviations of the in the Figures 3 and 4 shown embodiment received.

The Figures 3 and 4 also show how a dust housing 6 on the opposite side of the dust chamber opening 14 can taper in a funnel shape up to an air outlet 20, without turbulent flows would be generated by rapid air deflections or the like.

Furthermore, a receptacle 28 for a filter cartridge 30 or a filter is provided in the dust housing 6 between the dust chamber opening 14 and the air outlet 20, by means of which, for example, a fine dust filtration can be performed. In order to retain large particles of dirt, in some embodiments, a perforated plate or a perforated plate can furthermore be arranged on the dust space opening 14 on the inlet funnel 12. By means of this, an air flow can be directed to the filter cartridge 30 and it can also serve as a dust trap, so that an emerging from the dust chamber opening 14 coarse dirt can not fall back into the nozzle. The receptacle 28 for the filter cartridge 30 may be in the form of a shoulder in the housing. In other embodiments, other fasteners can be used for the receptacle 28, for example, detents by means of locking lugs or the like, jamming, a bayonet lock or fastening by means of screws. With other hosts come any form-fitting or non-positive connections into consideration.

It goes without saying that the dust collector filters are made of a variety of conventional filter materials, nonwoven fabrics or the like can.

Of course, filters for a dust collecting device can be used in any other geometries, for example, spherical, cylindrical or in the form of a truncated cone. In particular, a filter for a dust collecting device in the FIG. 1 shown type have a from the dust chamber opening 14 opposite side of the dust container in the direction of the dust chamber opening 14 extending and tapered deflecting body. Such filters may allow for different conditions different shapes of the baffles and possibly already have a filter function itself.

Claims (16)

Dust collecting device for a vacuum cleaner, in particular a hand vacuum cleaner, comprising: a nozzle (4) having a nozzle mouth (8) and a nozzle exit (10) adapted to direct air in a flow direction from the nozzle mouth (8) to the nozzle exit (10); a dust housing (6) adjoining the nozzle outlet (10) in the flow direction and having an inlet funnel (12) adjoining the nozzle outlet (10) and tapering from the nozzle outlet (10) to a dust chamber opening (14). Dust collecting device according to claim 1, wherein the inlet funnel (12) has the shape of a truncated cone. Dust collecting device according to one of claims 1 or 2, wherein an air-guiding cross-section of the nozzle (4) at the nozzle outlet (10) is greater than 70% of the air-conducting cross-section of the nozzle (4) on the nozzle mouth (8). Dust collecting device according to one of the preceding claims, in which the inlet funnel (12) is arranged inside a dust container (16) of the dust housing (6) surrounding the inlet funnel (12) such that between an outer wall of the inlet funnel (12) and an inner wall of the dust container (12). 16) a dust-receiving volume is formed. Dust collecting device according to claim 4, wherein the inlet funnel (12) and the dust container (16) are formed in the form of concentric truncated cones. Dust collecting device according to one of claims 4 or 5, wherein in the dust container (16) one from one of the dust chamber opening (14) opposite Side of the dust container (16) in the direction of the dust chamber opening (14) extending and tapering deflector (22) is arranged. Dust collecting device according to claim 6, wherein the baffle (22) has the shape of a cone. Dust collecting device according to one of claims 4 to 7, wherein the dust container (16) a plurality of protrusions (26) for receiving a filter element (24) extend into the dust-receiving volume. Dust collecting device according to one of claims 4 to 8, wherein the dust housing (6) has an air outlet (20) for discharging air in the flow direction from the dust housing (6), wherein the dust container (16) has a plurality of flow openings (18a). 18f) through which air can flow along different flow paths in the flow direction from the dust container (16) into the dust housing (6). Dust collection device according to claim 9, wherein a cross section of the plurality of flow openings (18a-18f) is larger for longer flow paths than for shorter flow paths. Dust collecting device according to one of the preceding claims, wherein an inner cross-section of the nozzle (4) from the nozzle mouth (8) to the nozzle outlet (10) changed such that the flow direction at the nozzle outlet (10) substantially tangential to an inner wall of the inlet funnel (12) runs. Dust collecting device for a vacuum cleaner according to any one of claims 1 to 3, wherein the nozzle (4) has a nozzle exit (10) with an elliptical or circular cross-section having a diameter or a large half-axis of at least 13 cm. A dust collecting device for a vacuum cleaner according to claim 12, wherein the inlet hopper (12) has a pinhole at the dust space opening (14). Dust collecting device for a vacuum cleaner according to claim 13, wherein the dust housing (16) tapers in a funnel shape on an opposite side of the dust chamber opening (14) to an air outlet (20). A dust collecting apparatus for a vacuum cleaner according to claim 14, wherein the dust housing (6) between the dust space opening (14) and the air outlet (20) further comprises a receptacle (28) for a filter cartridge (30). A filter (24) for a dust collecting device according to claim 8, comprising a deflecting body (22) extending and tapering toward the dust space opening (14) from a surface of the filter (24) opposite the dust space opening (14).

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