WO2014094876A1

WO2014094876A1 - Passive vacuum cleaner nozzle with an air intake aperture

Info

Publication number: WO2014094876A1
Application number: PCT/EP2012/076660
Authority: WO
Inventors: Roger Karlsson
Original assignee: Electrolux AB
Current assignee: Electrolux AB
Priority date: 2012-12-21
Filing date: 2012-12-21
Publication date: 2014-06-26
Anticipated expiration: 2015-06-21
Also published as: CN104703524A; CN104703524B; EP2934266B1; EP2934266A1

Abstract

According to an aspect of the present invention, a passive nozzle (1) for a vacuum cleaner is provided. The passive nozzle comprises a top part (2), a bottom part (3), and an airtight chamber (7) having a suction inlet (11) for the purpose of taking in dust from a surface to be cleaned and an outlet for connection to a fan unit of the vacuum cleaner. The top part comprises at least one air intake aperture (14) and the bottom part comprises an air outlet aperture (16). Further, the at least one air intake aperture of the top part is in fluid connection with the air outlet aperture of the bottom part. The present invention is advantageous in that the noise level is reduced.

Description

PASSIVE VACUUM CLEANER NOZZLE WITH AN AIR INTAKE APERTURE

Field of the invention

The present invention generally relates to the field of passive nozzles for vacuum cleaners. In particular, the present invention relates to passive nozzles with reduced noise level. Background of the invention

A passive nozzle is a nozzle without any rotary brushes or other means for actively agitating dust from a surface to be cleaned, and active nozzles are nozzles equipped with such means.

An issue in design of vacuum cleaners is to reduce the noise level generated during operation of the vacuum cleaner. Noise may arise from the fan unit of the vacuum cleaner, but also from airflow in the vacuum cleaner. Such airflow generates noise when it passes the nozzle of the vacuum cleaner.

The noise generated by the rotary brushes of active nozzles normally constitutes the major portion of the overall noise level of the active nozzle. Hence, the noise level of passive nozzles is in general lower than the noise level of active nozzles due to the absence of the noise from the rotary brush. It would be desirable to further reduce the noise level of such passive nozzles for vacuum cleaners.

Summary of the invention It is with respect to the above considerations that the present invention has been made. An object of the present invention is to provide an improved alternative to the above mentioned technique. More specifically, it is an object of the present invention to provide a passive nozzle for a vacuum cleaner with reduced noise level.

These and other objects of the present invention are achieved by means of a passive nozzle having the features defined in the independent claim.

Preferable embodiments of the invention are characterized by the dependent claims.

Hence, according to an aspect, a passive nozzle for a vacuum cleaner is provided. The passive nozzle comprises a top part, a bottom part, and an airtight chamber having a suction inlet for the purpose of taking in dust from a surface to be cleaned and an outlet for connection to a fan unit of the vacuum cleaner. The top part comprises at least one air intake aperture and the bottom part comprises an air outlet aperture. Further, the at least one air intake aperture of the top part is in fluid connection with the air outlet aperture of the bottom part. Conventional nozzles normally comprise means, such as brushes, supporting and spacing the bottom part of the nozzle with respect to the surface to be cleaned. In particular, such brushes may be used when cleaning hard surfaces, such as floors. When the nozzle is operated on the floor, the airflow generated by the fan unit of the vacuum cleaner enters the suction inlet of the nozzle generally via the space between the floor and the front, rear and lateral edges of the nozzle.

For cleaning soft surfaces, such as carpets, brushes are normally not used. The brushes may be retracted in the nozzle or a nozzle without brushes may be used. When operating the nozzle on the carpet, the air entrance at the front, rear and lateral edges of the nozzle may be at least partly blocked by the textile fibers of the carpet, e.g. as a consequence of the nozzle sinking down slightly in the carpet. As the air entrance at the front, rear and lateral edges of the nozzle is at least partly blocked, the air instead flows towards the suction inlet via the inside of the nozzle and is forced to pass small gaps, recesses and components in the nozzle. The air enters the nozzle via narrow gaps not initially intended for taking in air, such as narrow gaps (or slots) between assembled components of the nozzle. When the air is forced to pass such narrow gaps and the inner components of the nozzle, noise is

generated.

The present aspect uses the concept of having at least one air intake aperture for providing an additional entrance for the airflow. As the air intake aperture is located in the top part of the nozzle, the air intake aperture may not be blocked by the textile fibers of the carpet. Hence, when the nozzle is operated on a soft surface and the air entrance at the front, rear and lateral edges of the nozzle is partly blocked, air is also (or instead) entering the nozzle via the air intake aperture in the top part. The air then flows out of the air outlet of the bottom part, which is in fluid communication with the air intake aperture of the top part, and towards the suction inlet of the airtight chamber. As less air enters the nozzle via the narrow gaps, the noise level of the nozzle is reduced. Further, as the airtight chamber (which also may be referred to as a duct) of the nozzle is airtight, the suction force is improved since air enters the airtight chamber merely via the suction inlet.

The front and rear edges are the edges of the nozzle facing frontwards and rearwards, respectively, when the nozzle is moved in a natural forward direction (i.e. away from the user) during vacuum cleaning.

In an embodiment, the nozzle may be arranged so as to guide an airflow generated by the fan unit of the vacuum cleaner from the air inlet aperture of the top part and out of the air outlet aperture of the bottom part to the suction inlet of the airtight chamber. The fluid connection between the air inlet aperture of the top part and the air outlet aperture of the bottom part may be provided by a space (or passage) extending between the respective apertures in the nozzle. The air is guided from the air outlet aperture via the outside of the bottom part to the suction inlet. As the airflow is guided out of the bottom part (or nozzle) and then towards the suction inlet, i.e. via under side of the bottom part, it may be forced through the textile fibers of the carpet (or at least forced to pass the surface to be cleaned), whereby dust may be vacuumed form the carpet (or the surface to be cleaned).

According to an embodiment, the suction inlet of the airtight chamber may be defined between the portions of the bottom part arranged to be closest to the surface to be cleaned when the nozzle is operated. Hence, the suction inlet may be defined by the lowest portions of the bottom portion. The airtight chamber may thus extend from the lowest portion (such as a lower edge) of the bottom portion to the outlet for connection to a fan unit of the vacuum cleaner. According to an embodiment, a major portion of the total air intake area of the at least one air intake aperture may be located in lateral alignment with the suction inlet of the vacuum chamber. By lateral alignment, it is meant that a major portion of the total air intake area of the at least one air intake aperture is located over the suction port (seen from above, i.e. from the top part side of the nozzle). With the present embodiment, the air intake apertures are located closer to the suction inlet, whereby the path for the air to travel is reduced, which further reduces the noise level, as less components (or other interior) of the nozzle must be passed by the air.

According to an embodiment, the total air intake area of the at least one air intake aperture is at least 500 mm², such as at least 590 mm². An increased intake area facilitates air entrance through the air intake apertures and reduces the amount of air entering the nozzle through narrow gaps between components of the nozzle not initially intended for taking in air, whereby the noise level of the nozzle is reduced. In case of having a plurality of air inlet apertures, the total intake area is the sum of the area of each aperture.

According to an embodiment, the air intake area of each one of the at least one air intake aperture is smaller than 6 mm², such as smaller than 5.5 mm². Such size of the apertures reduces the risk of foreign matter entering the nozzle via the air inlet apertures. Further, a too large intake area of each air intake aperture may generate more noise at the apertures. Hence, the present embodiment reduces the noise level of the nozzle. According to an embodiment, the at least one air intake aperture may be substantially circular, which may further reduce the noise level. It will be appreciated that the term "substantially circular" may include any circular-like shape, such as geometrical shapes like a square or a polygon with

substantially rounded edges.

According to an embodiment, the passive nozzle may further comprise a passive brush being retractable towards the bottom part. A passive brush means a non-active brush, not being driven for agitating dust. Having the brush in its projected position is advantageous for operating the nozzle on hard surfaces, such as floors, for reducing the risk of scratching the floor and for sweeping dust from the floor. The brush may be retracted for operating the nozzle on soft surfaces, such as carpets, for bringing the suction inlet closer to the carpet, thereby increasing the suction force, and reducing the risk of the brush getting tangled in the textile fibers of the carpet. According to an embodiment, a vacuum cleaner is provided. The vacuum cleaner may comprise a passive nozzle as defined in any one of the preceding embodiments.

Brief description of the drawings

The above, as well as additional objects, features and advantages, will be better understood through the following illustrative and non-limiting detailed description of preferred embodiments, with reference to the appended drawings.

Figure 1 shows a passive nozzle according to an embodiment.

Figure 2 is a cross section of a nozzle body of the nozzle shown in Figure 1 . Figure 3 is an enlarged view of an air intake aperture of the nozzle shown in Figure 1 .

The figures are schematic, not necessarily to scale, and generally only show parts which are necessary in order to elucidate the invention, wherein other parts may be omitted or merely suggested. Detailed description of embodiments

With reference to Figures 1 to 3, a passive nozzle 1 of a vacuum cleaner according to an embodiment will be described.

The nozzle 1 may be of floor-type (i.e. adapted to clean floors or the like large cleaning surfaces).The nozzle 1 may comprise a nozzle body 15, which preferably may be elongated in a direction perpendicular to the normal (natural) direction of movement of the nozzle 1 during operation of the nozzle 1 . The nozzle body 15 is connected to a nozzle outlet 9 via a support structure 6. The nozzle outlet 9 is adapted for being connected to the suction hose of a vacuum cleaner (not shown), such that when the vacuum cleaner is in an operative mode, under pressure is created as air is sucked through the nozzle via the hose to the vacuum cleaner. The under pressure is generated by a fan unit of the vacuum cleaner. The fan unit may comprise a motor driven fan and may also be referred to as a motor/fan unit. The nozzle body 15 is pivotally connected with the support structure 6. This connection between the nozzle body 15 and the support structure 6 allows a limited degree of movement such that the nozzle body 15 is allowed to tilt as the nozzle 1 is moved forwards and backwards against the surface being cleaned during vacuuming. The nozzle 1 further comprise brushes 4, 5 mounted to the nozzle body 15 and preferably being manually or automatically retractable, such that the brushes 4, 5 can be retracted into the nozzle body 15 when the nozzle 1 is used for vacuuming carpets 10 or other soft surfaces (as illustrated in Figure 2) and projected when the nozzle 1 is used for vacuuming hard surfaces, such as floors (as illustrated in Figure 1 ). The brushes 4, 5 are of the passive type, i.e. they are substantially stationary, instead of driven to rotate, during cleaning. Further, the brushes 4, 5 may extend along the long sides of the elongated nozzle body 15, preferably along a front edge 12 and a rear edge 13, respectively, of the nozzle body 15, i.e. substantially perpendicular to the normal direction of movement of the nozzle 1 during operation of the vacuum cleaner. The nozzle body 15 comprises a top part 2 and a bottom part 3. The top part 2 may be an upper portion (such as an upper half) of the nozzle body 15, for example including (at least an upper portion of) a cover of the nozzle body 15. The bottom part 3 may be a lower portion (such as a lower half) of the nozzle body 15.

The nozzle body 15 further comprises an airtight chamber 7 (shown in Figure 2) having a suction inlet 1 1 (or suction port) for the purpose of taking in dust from the surface to be cleaned, and an outlet (not shown) for fluid connection to the fan unit via the nozzle outlet 9. The suction inlet 1 1 is arranged in the bottom part 3, i.e. on the underside of the nozzle body 15 (the side of the nozzle body 15 arranged to face the surface to be cleaned). It is important that the chamber is airtight to avoid leakage of air into the chamber 7, which reduces the suction force. Hence, the only inlet for air to the airtight chamber 7 is at the suction inlet 1 1 . The suction inlet 1 1 is defined between the portions 8 of the nozzle body 15 being closest to the surface to be cleaned when the nozzle 1 is supported on the surface, such as during vacuuming. Further, the suction inlet 1 1 may be elongated and extend along the

longitudinal direction of the elongated nozzle body 15, such as between the two opposing tips of the nozzle body 15. The top part 2 comprises one or more air intake apertures 14. Preferably, most of the air intake apertures 14 may be located over the suction inlet 1 1 (seen from above, i.e. from the top part side of the nozzle 1 ). Hence, most of the air intake apertures may be in lateral alignment with the suction inlet 1 1 . Further, the shapes of the air inlet apertures may preferably be substantially rounded, such as substantially circular (as shown in the enlarged view of an air intake aperture 14 in Figure 3). The air intake area of each one of the air intake apertures 14 may be smaller than 6 mm² and preferably smaller than 5.5 mm². It will be appreciated that the different air inlet apertures 14 may have different sizes. Further, the total air intake area of all the air inlet apertures 14 may be at least 500 mm² and preferably at least 590 mm².

The bottom part 3 comprise at least one air outlet aperture 16. In the present embodiment, the bottom part 3 comprises two air outlet apertures 16, one on each side of the suction inlet 1 1 (hence, one along the front edge 12 and one along the rear edge 13 of the nozzle body 15). The air outlet apertures 16 may be elongated and extend in the longitudinal direction of the elongated suction inlet 1 1 . The air outlet apertures 16 are arranged on the underside of the nozzle body 15 so as to face the surface to be cleaned. The air outlet apertures 16 are fluidly connected to the air inlet apertures 14, e.g. via a space (or passage) in the nozzle body 15 (e.g. a space between the cover and the airtight chamber 7).

An example of operation of the passive nozzle 1 will be described with reference to Figure 2 in the following.

When the fan unit of the vacuum cleaner is operated, an airflow (indicated by arrows in Figure 2) towards the suction inlet 1 1 is generated. If the nozzle 1 is operated on a carpet 10, the nozzle 1 may sink down slightly in the textile fiber of the carpet 10, which causes the gap below the front and rear edges 12, 13 to be at least partly blocked by the textile fibers. At least a portion of the airflow enters the nozzle 1 via the air inlet apertures 14 in the top part of the nozzle 1 . The airflow is then guided (e.g. via the space between the cover and the airtight chamber 7) towards, and then out of, the air outlet apertures 16 of the bottom part 3 at the underside of the nozzle body 2. The airflow then passes the underside of the bottom part 3 through the textile fibers of the carpet 10 towards, and then into, the suction inlet 1 1 . As the airflow passes the underside of the bottom part 3, dust is brought by the airflow to the suction inlet 1 1 .

While specific embodiments have been described, the skilled person will understand that various modifications and alterations are conceivable within the scope as defined in the appended claims.

Claims

1 . A passive nozzle (1 ) for a vacuum cleaner, the passive nozzle

comprising:

a top part (2),

a bottom part (3), and

an airtight chamber (7) having a suction inlet (1 1 ) for the purpose of taking in dust from a surface to be cleaned and an outlet for connection to a fan unit of the vacuum cleaner, wherein:

the top part comprises at least one air intake aperture (14), the bottom part comprises an air outlet aperture (16), and the at least one air intake aperture of the top part is in fluid connection with the air outlet aperture of the bottom part.

The passive nozzle as defined in claim 1 , wherein the nozzle is arranged so as to guide an airflow generated by the fan unit of the vacuum cleaner from the air inlet aperture of the top part and out of the air outlet aperture of the bottom part to the suction inlet of the airtight chamber.

The passive nozzle as defined in claim 1 or 2, wherein the suction inlet of the airtight chamber is defined between the portions (8) of the bottom part arranged to be closest to the surface to be cleaned when the nozzle is operated.

The passive nozzle as defined in any one of the preceding claims, wherein a major portion of the total air intake area of the at least one air intake aperture is located in lateral alignment with the suction inlet of the vacuum chamber.

5. The passive nozzle as defined in any one of the preceding claims, wherein the total air intake area of the at least one air intake aperture is at least 500 mm².

6. The passive nozzle as defined in any one of the preceding claims, wherein the air intake area of each one of the at least one air intake aperture is smaller than 6 mm².

7. The passive nozzle as defined in any one of the preceding claims, wherein the at least one air intake aperture is substantially circular.

8. The passive nozzle as defined in any one of the preceding claims, further comprising a passive brush being retractable towards the bottom part.

9. A vacuum cleaner comprising a passive nozzle as defined in any one of the preceding claims.