WO2006042553A1

WO2006042553A1 - A vacuum cleaner having an interference creating arrangement for sound damping

Info

Publication number: WO2006042553A1
Application number: PCT/DK2005/000679
Authority: WO
Inventors: Søren KRAGELUND; Ole Nerst
Original assignee: Nilfisk-Advance A/S
Priority date: 2004-10-20
Filing date: 2005-10-20
Publication date: 2006-04-27
Also published as: EP1809158B1; ES2346455T3; EP1809158A1; ATE468799T1; DE602005021529D1

Abstract

A vacuum cleaner having an interference creating arrangement comprises at least a first (1) channel having an inlet opening which is terminated by an outlet opening (5) provided perpendicularly to the channel, as well as a transverse wall (4) provided perpendicularly to the channel, said wall having a height (B) which is smaller than the height (H) of the channel. A further channel (6) is provided in connection with the outlet opening (5) and extends in parallel with the first channel. In some embodiments the interference creating arrangement is configured as a lattice (14), which is composed as a plurality of parallel channels (15) of the type described above, or as an exhaust channel. The invention provides an interference creating arrangement which may be manufactured a low costs by moulding in one piece.

Description

A VACUUM CLEANER HAVING AN INTERFERENCE CREATING ARRANGEMENT FOR SOUND DAMPING

The invention relates to a vacuum cleaner having an interference creating arrangement, said interference creating arrangement comprising at least a 5 first channel having an opening which is positioned in a direction toward the vacuum cleaner motor in the exhaust or intake air thereof, and being termi¬ nated at its other end by a wall or an opening, said wall being disposed perpendicularly to the main propagation direction of the air and the sound.

10 The invention moreover relates to an interference creating arrangement for a vacuum cleaner.

US Patent No. 4,970,753 discloses a vacuum cleaner having an interfer¬ ence creating arrangement of the type defined in the introductory portion of

15 claim 1. According to the US patent, the interference creating arrangement is composed as a two-part housing having two inlet openings which are connected with their respective channels, through which exhaust air from the motor and the fan blade of a vacuum cleaner is conveyed toward its respective wall and labyrinths in the two-part housing.

20

This structure is rather expensive to manufacture, since the housing must necessarily be made of two parts for manufacturing reasons.

Accordingly, an object of the invention is to provide a vacuum cleaner hav- 25 ing an interference creating arrangement which is easier to manufacture.

The object of the invention is achieved by a vacuum cleaner of the type de¬ fined in the introductory portion of claim 1 , which is characterized in that the wall has a height which is equal to or smaller than the height of the channel. 30

Hereby, it is possible to provide the interference creating arrangement by the moulding of just one piece.

Expedient embodiments of the vacuum cleaner having the interference cre¬ ating arrangement according to the invention are defined in claims 2 - 4.

As mentioned, the invention also relates to an interference creating ar¬ rangement.

This interference creating arrangement is characterized in that it is con- structed as a lattice having a plurality of parallel channels, or as an exhaust channel or an intake channel as defined in claims 1 - 4.

Hereby, the interference creating arrangement may be manufactured and adapted to the geometry of any vacuum cleaner in a simple manner.

The invention will now be explained more fully with reference to the draw¬ ing, in which

fig. 1 shows the principle underlying the invention,

fig. 2 shows a vacuum cleaner motor in a housing, where the interference creating arrangement according to the invention is incorporated in the housing, while

fig. 3 schematically shows a lattice for a vacuum cleaner which is constructed according to the principles of the invention.

In fig. 1 , the numeral 1 designates a channel to which exhaust air or intake air, e.g. from a vacuum cleaner, is conveyed in the direction of the arrow 2.

At its remote end, the channel is terminated by a smooth wall 4 from which the exhaust air or the intake air is reflected as shown by the arrow 3, which means that the exhaust air or the intake air passing through an opening 5, which is disposed perpendicularly to the channel 1 , is damped.

To achieve the best damping, the length of the channel L must be 10 mm or more, so as to achieve destructive interference between the reflecting wave from the wall and the wave which is sent into the channel of the length L.

As will additionally be seen in fig. 1 , a further channel 6 is provided, said further channel being disposed in parallel with the channel 1 and connected with the opening 5.

According to the invention, the wall 4 has a height B which is equal to or smaller than the length L of the channel 1. Hereby, the channels 1 , 6 may be moulded in one piece, which means lower manufacturing costs.

In fig. 2, the numeral 8 designates a vacuum cleaner motor which drives a fan blade (not shown), which is disposed inside a housing having openings 9 through which exhaust air originating from a vacuum cleaner hose (not shown) arrives, as shown by the arrow 7, and is driven into the motor com¬ partment of the vacuum cleaner, where the air is conveyed from openings 9 to channels 12, 13 in the directions of the arrows 10, 11.

These channels are configured as shown in fig 1 and will affect the interfer- ence of the exhaust air, which arrives from the motor 8 and the fan blade, quite considerably.

Fig. 3 shows a cross-section of a lattice which is configured using the prin¬ ciples of the invention.

As will be seen, the lattice consists of a number of parallel channels 15, 16, said channels 15 being terminated by walls 17.

Such a lattice is relatively inexpensive to manufacture and is easy to adapt to several types of vacuum cleaners as a loose part which may be inserted into the vacuum cleaner.

Although the invention has been explained by specific exemplary embodi¬ ments, nothing prevents the embodiments from being modified within the scope of the claims.

It is conceivable, e.g., that the lattice in fig. 3 was provided with channels which have a varying length so that it may be adapted to the spectral com¬ position of a source of sound.

Claims

PATENT CLAIMS

1. A vacuum cleaner having an interference creating arrangement, said interference creating arrangement comprising at least a first (1) channel having an opening which is positioned in a direction toward the vacuum cleaner motor in the exhaust or intake air thereof, and being terminated at its other end by a wall and an opening, said wall being disposed perpen¬ dicularly to the main propagation direction of the air and the sound, char¬ a cte ri z ed in that the wall (4) has a height (B) which is equal to or smaller than the height (H) of the channel.

2. A vacuum cleaner according to claim 1, characterized in that the wall (4) is disposed perpendicularly relative to the sound propagation direc¬ tion (2) in the first channel.

3. A vacuum cleaner according to claims 1 -2, characterized in that a further channel (6) is provided in extension of the outlet opening, said further channel extending in parallel with the first channel (1 ).

4. A vacuum cleaner according to claims 1 -3, characterized in that the length L of the first channel is 10 mm or more.

5. An interference creating arrangement for a vacuum cleaner, which is composed as a lattice (14) having a plurality of parallel channels (15), or as an exhaust channel or an intake channel as defined in claims 1 - 4.