WO2016113195A1 - Cleaning device and method for reducing noise in a cleaning device - Google Patents

Abstract

Disclosed is a cleaning device comprising at least one source of noise (33) emitting noise in a frequency range below 2000 Hz, and at least one perforated-panel resonator (84) associated with the at least one source of noise (33); the at least one perforated-panel resonator (84) includes a chamber (85) having a chamber space (88) and a chamber wall (86), and at least one perforated panel (90) that covers the chamber space (88); the at least one perforated panel (90) is sound-effectively connected to the at least one source of noise (33).

Description

 Cleaning device and method for reducing noise in a

 Cleaning Appliance The present application claims priority of German Application No. 10 2015 100 426.7 of January 13, 2015. The content of said German patent application is incorporated by reference in its entirety and for all purposes. The invention relates to a cleaning device comprising at least one noise source with a noise emission in a frequency range below 2000 Hz.

Furthermore, the invention relates to a method for noise reduction in a cleaning device, which has a noise source that generates noise in a frequency range below 2000 Hz.

From EP 1 785 080 Bl a silencer device for a vacuum cleaner is known, which comprises a plurality of elongate tubes.

From JP 2009-100840 A, an electric fan and an electric vacuum cleaner with a corresponding fan is known in which a motor is arranged in a soundproof housing. There is provided an exhaust passage, are arranged on which sound-absorbing materials. A sound absorbing material is disposed on a film or a porous plate.

From EP 2 657 932 Al a sound insulating plate is known which does not hinder an air flow.

From DE 601 25 367 T2 (EP 1 303 209 B1) is a suction device with noise reduction means in one or more air flow channels for reducing the noise emission from an air flow generator or The like is known, wherein at least one air flow channel is provided with a plurality of depressions, which are arranged one behind the other in the direction of the air flow, wherein the depressions have a predetermined depth, which extend substantially perpendicular to the general direction of the noise in the channel. The recesses are formed by providing on at least one side of the flow channel protruding wall parts, which wall parts are integrally formed in housing parts of the suction device, which define the air flow channel. From DE 43 15 759 Cl a sound-absorbing glass component or transparent plastic glass component is known.

From DE 195 17 197 AI a vacuum cleaner with a device for cleaning a filter is known.

From DE 197 47 318 AI a cleaning device is known, which has a pump and a suction unit, wherein the pump and the

Suction unit are held in a separate housing which is insertable in the form of a slot in a frame of the cleaning device.

From WO 2012/107103 Al a method for cleaning at least one filter of a vacuum cleaner is known.

From EP 1 120 075 Al a turbo brush for cleaning a surface is known.

The invention has for its object to provide a cleaning device of the type mentioned, in which with respect to noise in a frequency range below 2000 Hz effective noise reduction is achieved.

This object is achieved according to the invention in the cleaning device mentioned above in that at least one perforated plate resonator provided is, which is associated with the at least one noise source, wherein the at least one perforated plate resonator comprises a chamber having a chamber space and a chamber wall and at least one perforated plate which covers the chamber space, and wherein the at least one perforated plate is acoustically connected to the at least one noise source.

A perforated plate resonator (perforated plate absorber) has a resonator space over the chamber space, which is bounded on one side in particular by a perforated plate. By means of a perforated plate resonator, noises in the low frequency range (in particular less than or equal to 2000 Hz) can be effectively reduced by sound absorption.

In particular, sound absorption takes place on a perforated plate resonator by the friction of an oscillating air column at an opening wall of holes of the at least one perforated plate of the perforated plate resonator.

The at least one perforated plate is a plate which is provided with a plurality of openings. This is acoustically connected to the at least one noise source, that is, sound waves of the noise source propagate in the direction of the perforated plate. Sound absorption with effective noise reduction can then be achieved at the perforated plate resonator. The chamber may have one or more subspaces. It has been found that, for example, noise in a vacuum cleaner, which are generated by a filter cleaning over external air, can be attenuated so that a noise reduction in the maximum level of more than 2.5 dB and in particular of about 5 dB or more can be achieved. A perforated plate resonator is in particular determined by its resonance frequency (center frequency), the geometric dimensions of the chamber space, the geometric dimensions of the openings in the perforated plate, and the arrangement of the openings on the perforated plate, in particular via the ratio of the area of an opening on the perforated plate to the total area of the perforated plate. By appropriate dimensioning can be for a specific noise source, for example, with bangs an effective

Generate noise reduction.

The specified frequency range for the noise emission does not mean that noises are emitted only in this frequency range. There may also be higher-frequency noise. The at least one perforated plate resonator is used to attenuate the low-frequency noise below 2000 Hz. Other means may be provided for attenuating higher-frequency noises.

In one embodiment, the at least one perforated plate is arranged on the chamber wall and in particular a (lateral) wall of the chamber wall is supported on the perforated plate. This makes it possible, in particular, to form a perforated plate resonator as a type of box, which can be positioned in a simple manner on a cleaning device such as, for example, a vacuum cleaner. It is particularly advantageous if the at least one perforated plate of the at least one perforated plate resonator has a first side which faces the chamber space and has a second side which lies opposite the first side, wherein a plurality of openings is provided in the at least one perforated plate which are continuous between the first page and the second page. This can be an effective

Achieve sound absorption.

In a manufacturing technology simple embodiment, the first side and / or the second side are flat. A corresponding perforated plate can be produced in a simple manner.

For the same reason, it is favorable if the first side and the second side are parallel to each other. In one embodiment, the openings on the first side open into the chamber space and are facing on the second side of the at least one noise source. It can thereby penetrate sound into the chamber space to effect an effective sound absorption.

In one embodiment, the openings on the second side open into a channel which is acoustically connected to the at least one noise source. Due to the friction of an oscillating air column at an opening wall of a hole of the at least one perforated plate, an effective sound absorption can take place.

It is advantageous if at least one sound-conducting channel is provided which leads from the at least one noise source to the at least one perforated plate. It can then be derived from a sound source of sound to effect effective absorption. As a result, the at least one perforated plate resonator can be arranged optimally on a cleaning device and, in particular, also at a distance from the at least one

Arrange noise source.

In one embodiment, the at least one perforated plate forms a housing, within which the at least one noise source is arranged. This can achieve a "large-scale" noise reduction. For example, sound propagation from the at least one noise source can achieve effective noise reduction on all sides.

It can then be provided that the chamber wall of the at least one perforated plate resonator at least partially forms a housing wall of the cleaning device. This results in a teileminimierender structure of the cleaning device.

In one embodiment, the chamber wall has a cover wall which faces the at least one perforated plate, and has a (Lateral-) wall, which lies between the top wall and the at least one perforated plate. The (lateral) wall forms side walls which laterally surround the chamber space. In a manufacturing technology advantageous embodiment, the at least one perforated plate and the top wall are aligned in parallel. A corresponding perforated plate resonator can also be calculated in a simple manner with regard to its sound absorption properties. For the same reason, it is favorable if the chamber space a

(Hollow) has cuboid shape.

In a manufacturing technology favorable embodiment, the chamber wall comprises a first transverse wall, a second transverse wall, a first longitudinal wall, a second longitudinal wall and a top wall, wherein the first

Are spaced apart and assign each other, the first longitudinal wall and the second longitudinal wall are spaced apart and assign each other, the first transverse wall and the first longitudinal wall are oriented transversely to each other, and the cover wall transverse to the first transverse wall, the second transverse wall, the first longitudinal wall and the second longitudinal wall is oriented. The corresponding perforated plate resonator has a box shape. Such a perforated plate resonator can be easily accommodated on a cleaning device. For the same reason, it is favorable if the first transverse wall and the second transverse wall are oriented in parallel and / or the first longitudinal wall and the second longitudinal wall are oriented in parallel. It can thereby realize a perforated plate resonator, which has a cuboid chamber space. The absorption properties of a perforated plate resonator can be easily calculated in such a design. This in turn allows a simple adaptation to given conditions in a cleaning device and in particular a frequency adjustment in a simple manner. It is advantageous if the chamber wall is at least partially made of a reverberant material. A reverberant material is understood to mean a material with a reflectance of at least 94%. A reverberant material has a low sound absorption. It is then provided for an effective noise reduction.

It can be provided that at least partially a sound absorption material such as mineral fiber wool is arranged in the chamber space. This results in a more effective sound absorption.

In particular, the at least one noise source has a low-frequency noise emission, and a noise emission in a frequency range below 1000 Hz or less. Typically, for example, an external air valve device for cleaning a filter device of a vacuum cleaner generates noises with a frequency below 1000 Hz, for example at approximately 700 Hz.

It may be provided that the at least one noise source produces blast noises, that is to say generates noises with a relatively short duration, for example of 50 ms or less. For example, generates an external air valve device in the training as a cleaning device for a filter device of a vacuum cleaner corresponding bang noises. Through a perforated plate resonator, which is assigned to such a noise source, can effectively dampen pops.

It is provided that the at least one perforated plate resonator with respect to its geometric dimensions and arrangement and formation of openings in the at least one perforated plate with respect to the at least one noise source is dimensioned so that through the at least one perforated plate resonator, a noise reduction in the maximum level of at least 2.5 dB he follows. The at least one noise source generates, for example, bang noise due to a pressure change, wherein the pressure change is in particular greater than 50 mbar, and generates the pressure change, in particular in a period of less than 0.05 s. When cleaning a filter device of a vacuum cleaner via an external air valve, such a pressure drop takes place in the appropriate period and then low-frequency bang noises are generated.

In one embodiment, the cleaning device is designed as a vacuum cleaner.

The vacuum cleaner (in particular vacuum cleaner) comprises, for example, a suction unit, a dirt collecting container and a filter device, wherein the dirt collecting container is in flow connection with the suction unit via the filter device. The sucker also has a cleaning device for the filter device, wherein the at least one perforated plate resonator is assigned to the cleaning device. By means of the cleaning device it is possible to prevent a filter with

Adds dirt. For example, in WO 2012/107103 Al a method for cleaning a filter of a vacuum cleaner is described, in which the suction power of a suction unit is increased before a transition of an external air valve in an open valve position and later reduced again. This document is expressly incorporated by reference.

In particular, the cleaning device comprises an external air valve device. The external air causes a sudden pressure change, which leads to filter cleaning. This sudden pressure change also causes blasts of noise. By the solution according to the invention an effective noise reduction is achieved with respect to such bang noises. The at least one perforated plate resonator with the at least one perforated plate is in this case arranged opposite the cleaning device, in particular, wherein in particular a sound-conducting channel is arranged between the discharge device and the cleaning device. cleaning device and the at least one perforated plate is arranged. This achieves effective noise reduction.

In a further embodiment, a dispensing device for a cleaning fluid is provided which comprises at least one pump, wherein the at least one perforated plate resonator is associated with the at least one pump. The pump can be a source of low-frequency noise. Over the at least one perforated plate resonator, an effective noise reduction can be achieved. Such a cleaning device is for example a high-pressure cleaner or a steam cleaner.

In one embodiment, the at least one perforated plate houses the at least one pump. It can thereby achieve an all-round sound absorption by the at least one perforated plate resonator.

According to the invention, a perforated plate resonator is used for noise reduction on a cleaning device, wherein the cleaning device comprises at least one noise source that generates noise in a frequency range below 2000 Hz (and in particular of 1000 Hz or less).

According to the invention, a method for noise reduction in a cleaning device having a noise source, the noise in a frequency range below 2000 Hz (and in particular 1000 Hz or less), provided, in which a sound effective connection between the at least one noise source and at least one perforated plate of the at least one perforated plate resonator is or is made.

The advantages of the method according to the invention have already been explained in connection with the cleaning device according to the invention.

Further advantageous embodiments of the method according to the invention have also already been explained in connection with the cleaning device according to the invention. The following description of preferred embodiments is used in conjunction with the drawings for further explanation of the invention. Show it :

Figure 1 is a schematic sectional view of an embodiment of a (dust) teat as an example of a cleaning device; an enlarged view of an external air valve device of the nipple according to Figure 1; a partial perspective view of the teat according to Figure 1 with a perforated plate resonator; a sectional view of the perforated plate resonator according to Figure 3; and a schematic sectional view of an embodiment of a high-pressure cleaner as an example of a clean ing device.

An embodiment of a (dust) vacuum cleaner 10 as an example of a cleaning device, which is shown schematically in Figure 1 in a sectional view, has a dirt collecting container 12, on which a suction head 14 is placed. The vacuum cleaner 10 is an example of a vacuum cleaner and designed as a stand-alone device (as an autonomous device). The dirt collecting container 12 has a suction inlet 16 to which a suction hose 18 can be connected in the usual way. The suction head 14 seals the dirt collecting container 12 on the upper side and forms a suction outlet 20, on which a filter device 21 with (at least) a filter 22 is held. The filter 22 is followed by a suction line 24, via which the dirt collecting container 12 with a suction unit 26 in flow Connection stands. The suction unit 26 comprises an electric motor device 25 with (at least) an electric motor 27 and a rotationally driven by the electric motor 27 blower 28. The dirt collecting 12 is acted upon by the vacuum unit 26 during operation of the vacuum cleaner 10 with negative pressure, so that in Figure 1 by the arrows 30 illustrated suction flow forms. Under the effect of the suction flow 30, suction air loaded with dirt can be sucked in via the suction inlet 16 into the dirt collecting container 12, which can then be sucked off by the suction unit 26. The suction air can be discharged from the suction unit 26 via exhaust ports 29 (Figure 7) of the suction head 14 to the environment.

The suction air flows through the filter 22, so that entrained solid particles deposit on the dirt collecting container 12 facing the dirty side 32 of the filter 22. It is therefore necessary to clean the filter 22 from time to time, since otherwise it forms an increasing flow resistance, whereby the suction effect of the vacuum cleaner 10 is impaired. For cleaning the filter 22, a cleaning device, which is designed as an external air valve device 33, with (at least) an external air valve 34 is disposed above the filter 22 in the suction head 14 (shown enlarged in Figure 2). It comprises a stationary in the suction head 14 arranged valve holder 36 which forms a valve seat for a movable valve body in the form of a valve disk 38. The valve disk 38 is by means of a

Closing spring 40 is acted upon by a closing force in the direction of the valve holder 36. The closing spring 40 is clamped between a plate-like, a plurality of flow passages, fixedly arranged in the suction head 14 filter holder 42 and the valve plate 38. In addition to the closing spring 40, the filter holder 42 carries a resilient stop element in the form of a stop spring 44. This particular (preferably as well as the closing spring 40) has a linear characteristic. It is for example designed as a helical spring. In contrast to the closing spring 40 is the stopper spring 44 in the closed position of the valve plate 38 is not under tension. Only when the valve disk 38 lifts from the valve seat of the valve holder 36, the stopper spring 44 comes to rest on the underside of the valve disk 38 and is slightly compressed in a further movement of the valve plate 38. It thus exerts an increasing restoring force on the valve disk 38 and accelerates the movement of the valve disk 38 from its closed valve position (shown in FIG. 2) back to the closed valve position via an open valve position. In the open valve position, the valve plate 38 takes a distance to the valve holder 36, which forms the valve seat.

The valve holder 36 has a plurality of passage openings, not shown in the drawing, whose mouth areas are closed by the valve disk 38 when it assumes its closed valve position. At the level of the valve holder 36, the suction head 14 has a lateral opening 46. Via the lateral opening 46, foreign air can flow into the passage openings of the valve holder 36. If the valve disk 36 has its open valve position spaced from the valve holder 36, the lateral opening 46 is in fluid communication with the suction line 24 via the passage openings of the valve holder 36 and the clean side 48 of the filter 22 facing away from the dirt collecting container 12 can act on it. If the valve disk 38 assumes its closed valve position, the flow connection between the lateral opening 46 and the suction line 24 is interrupted.

In a central region, the valve holder 36 carries an electromagnet 50. In the circumferential direction of the electromagnet 50 is surrounded by an annular space 52, in which a molded upper side of the valve plate 38 guide sleeve 54 dips. The guide sleeve 54 receives a magnetizable element, for example in the form of an iron plate 56, which abuts in the closed valve position of the valve disk 38 at a free end edge 58 of the electromagnet 50 and 50 forms a closed magnetic circuit in combination with the electromagnet. The electromagnet 50 is connected via a power supply line with an arranged in the suction head 14 (electronic) control device 62 in electrical connection. From the control device 62, the solenoid 50 is acted upon during the normal suction operation of the vacuum cleaner 10 with a supply current. Due to the forming magnetic field of the valve plate 38 is reliably held in its closed position. The holding force of the electromagnet 50 is determined by the spring force of

Closing spring 40 supported.

If the power supply of the electromagnet 50 is interrupted by the control device 62, the magnetic holding force acting on the valve disk 38 is eliminated and the valve disk 38 becomes inactive due to the pressure difference acting on it, resulting from the external pressure of the external air present in the area of the valve holder 36 and the internal pressure within the suction line 24 results, lifted against the action of the closing spring 40 from the valve seat. External air can then flow abruptly through the passage openings of the valve holder 36 into the suction line 24 and the filter 22 is acted upon abruptly on its clean side 48 with external air. This leads to a mechanical vibration of the filter 22.

 In addition, the filter 22 is flowed through in the counter-current direction, that is, contrary to the prevailing during the normal suction operation flow direction 30, from external air. This results in an effective cleaning of the filter 22.

The energy supply of the vacuum cleaner 10 is carried out in one embodiment by means of a rechargeable battery device. This includes, for example, two rechargeable batteries. The battery device comprises, for example, one or more lithium-ion batteries. These are arranged laterally next to the suction unit 26 in a battery compartment 68 of the suction head 14. The battery compartment 68 is accessible via an outwardly pivotable flap 70 the user to replace the batteries. The electronic control device 62 is arranged above the suction unit 26 in the suction head 14 and is connected via supply lines to the batteries 64 in electrical connection. On the input side, a user-actuated push-button 82, which is arranged on the upper side of the suction head 14, is connected to the control device 62. By pressing the button 82, the user can (manually) trigger a filter cleaning.

The external air valve device 33 in the vacuum cleaner 10 is a source of noise for low-frequency noise and in particular blast noise. The sudden ("sudden") pressure change, which leads to a mechanical vibration of the filter 22, leads to low-pitched pop noise. These are usually well below 1000 Hz or less. The pressure reduction is abrupt and has a duration of less than 0.05 s. The pressure change is in particular 50 mbar (5 kPa) or more.

For noise reduction with respect to this noise source, the sucker 10 is provided with a perforated plate resonator 84 (FIGS. 1, 3, 4). The perforated plate resonator 84 is assigned to the external air valve device 33 as a noise source and connected to it in a sound-effective manner.

The perforated plate resonator 84 has (FIG. 4) a chamber 85 with a chamber wall 86. This chamber wall 86 limits one

Chamber chamber 88. The chamber chamber 88 is closed by a perforated plate 90.

In one embodiment (Figure 4), the orifice plate 90 is supported on the chamber wall 86 and is disposed thereon. For example, the chamber wall 86 is connected to the perforated plate 90.

In one embodiment, the chamber wall 86 includes a top wall 92. This top wall 92 is spaced from the orifice plate 90 and this opposite. Between the lid wall 92 and the perforated plate 90, the chamber space 88 is formed.

In one embodiment, the perforated plate 90 and the lid wall 92 are parallel to each other.

The perforated plate 90 has a first side 94. The first side 94 is the

Chamber chamber 88 facing. It is also the top wall 92 facing. The perforated plate 90 further includes a second side 96. The second side 96 faces the first side 94. Between the first side 94 and the second side 96, the perforated plate 90 extends.

The second side 96 of the perforated plate 90 is acoustically effective facing the noise source (in the vacuum cleaner 10 of the external air valve device 33). Sound waves can propagate from this noise source to the perforated plate 90 and enter the chamber space 88 through openings ("holes") in the perforated plate 90.

In one embodiment (FIG. 4), the first side 94 and the second side 96 are parallel to each other. The perforated plate 90 is then formed correspondingly flat.

In one embodiment, the orifice plate resonator 84 includes a first transverse wall 98 and a second transverse wall 100. These are spaced apart from each other.

For example, they are aligned parallel to each other.

The first transverse wall 98 and the second transverse wall 100 sit against the top wall 92 and protrude transversely beyond them. Further, the apertured plate resonator 84 includes a first longitudinal wall 102 and a second longitudinal wall 104. The first longitudinal wall 102 and the second longitudinal wall 104 are spaced apart from each other and toward one another. The first longitudinal wall 102 and the second longitudinal wall 104 are formed, for example, parallel to each other.

The first longitudinal wall 102 and the second longitudinal wall 104 are seated on the

Lid wall 92 and protrude beyond this. The first longitudinal wall 102 and the second longitudinal wall 104 are transverse to the first transverse wall 98 and the second transverse wall 100. The first transverse wall 98, the second transverse wall 100, the first longitudinal wall 102, and the second longitudinal wall 104 form a (lateral) wall 106. which sits on the top wall 92 and closes the chamber space 98 laterally. In turn, the perforated plate 90 is arranged on this wall 106 and is supported, in particular, on end faces of this wall 106.

In one embodiment, the first transverse wall 98, the second transverse wall 100, the first longitudinal wall 102, and the second longitudinal wall 104 are straight. The transverse walls 98, 100 are formed at right angles to the longitudinal walls 102, 104. The chamber space 88 has a hollow cuboid shape.

The chamber wall 96 is formed in particular of a reverberant material with a reflectance greater than 94%, which has a low absorption capacity for sound.

In the perforated plate 90, openings ("holes") 108 are arranged which are continuous between the first side 94 and the second side 96. At the first side 94, the openings open into the chamber space 88. At the second side 96, the openings 108 open into a channel 110 (FIG. 1), which is sound conducting. The channel 110 is disposed between the noise source, that is, the external air valve device 33, and the orifice plate 90. On the perforated plate 90, a plurality of openings 108 is formed. These are especially arranged regularly. They are arranged in particular on grid points of a two-dimensional grid. Elementary cells of this grid are, for example, squares, rectangles, trapezoids, triangles, etc.

In one embodiment, the openings 108 have a circular cross-section. As a result, they have a (hollow) cylindrical shape.

An extension direction 112 of an opening 108 is oriented, for example, parallel to the transverse walls 98, 100 or longitudinal walls 102, 104. The extension direction 112 is oriented in particular perpendicular to the first side 94 and second side 96 of the perforated plate 90. It is also oriented in particular perpendicular to the top wall 92. In the chamber chamber 88 may wholly or partially be arranged a sound-absorbing material 114 as mineral fiber wool.

The perforated plate resonator 84 is a perforated plate absorber having sound absorbing properties. By a reverberant training of the chamber wall 86, that is, by correspondingly low sound absorption capabilities of the chamber wall 86, the sound-absorbing effect is improved.

The dimensioning of the perforated plate resonator 84 with respect to its geometrical dimensions and the arrangement and dimension of the openings 108 determines the effective frequency range for the sound absorption.

With a geometrical structure of the perforated plate resonator 84 as shown in FIG. 4 with a parallelepiped chamber space 88 and mutually perpendicular transverse walls 98, 100 and longitudinal walls 102, 104, wherein the wall 106 in turn is perpendicular to the perforated plate 90 and the top wall 92, this results in a Center frequency f ₀ as

I is the thickness of the perforated plate 90 between the first side 94 and the second side 96 plus an orifice correction; d is the height of the chamber space 88 between the first side 94 of the perforated plate 90 and an inner side of the cover wall 92; c is the speed of sound (see R. Lerch, G. Sessler, D. Wolf, "Technical Acoustics", Springer 2009, p. 296). The above formula applies to circular openings 108 with a diameter 2r.

The size ε results ε = opening area I total area (2)

The opening area is the opening area (mouth area) of an opening 108. The total area is the total area of the perforated plate 90 which is exposed to the noise source, that is, which is acted upon by sound waves.

In the vacuum cleaner 10, the total area 10 corresponds to that area of the perforated plate 90 which assigns the channel 110.

In a typical embodiment, in particular for a vacuum cleaner with external air valve device 33, the perforated plate resonator 84 is designed such that the center frequency f ₀ is approximately 675 Hz.

It has been possible to realize a noise reduction of the maximum level by more than 2.5 dB and, for example, by approximately 5 dB for a vacuum cleaner 10 with an external air valve device. Basically, a perforated plate resonator has the following characteristic variables: resonance frequency (center frequency), opening diameter, Resonator height (height of the chamber space), thickness of the perforated plate and hole spacing. For a specific application, these variables are set so that there is sufficient noise reduction for the relevant frequencies, for example at a maximum level of more than 2.5 dB.

A perforated plate resonator can also be used in conjunction with other cleaning devices that include low-frequency noise emission noise sources in a frequency range below 2000 Hz. An exemplary embodiment of a further cleaning device is, as shown schematically in FIG. 5, a high-pressure cleaner 116. This high-pressure cleaner comprises a discharge device 118 for cleaning fluid and in particular water. For high-pressure delivery of the fluid, a pump 120 is provided. This pump 120 can form a source of noise for low-frequency noise; in particular in connection with the switching on of the pump for fluid delivery.

In one embodiment, an apertured plate resonator 122 is provided which includes a chamber 129 having one or more apertured plates 124.

In one embodiment, the perforated plate or plates 124 form a housing 126 for the noise source 120. Sound waves originating from the noise source 120 and radiated on all sides inevitably strike the perforated plate or plates 124.

The high-pressure cleaner 116 has a housing wall 128. The housing wall 128 forms a chamber wall 130 of the chamber 129 of the perforated plate resonator 122, or the chamber wall 130 is located near the housing wall 128. A chamber space 132, which is a resonator chamber, lies between the or the perforated plates 124 and the chamber wall 130 surrounds the noise source 120. The perforated plate resonator 122 is designed and dimensioned with regard to its relevant variables in such a way that a relevant reduction in noise (in particular in the maximum level by more than 2.5 dB) is produced for resulting low-frequency noises.

In the embodiment of the high-pressure cleaner 116, the chamber space 132 has no cuboid shape. It is adapted to the formation of the housing wall 128 with a perforated plate housing of the pump 120. The perforated plate resonator 122 basically functions the same as the perforated plate resonator 84.

Reference number vacuum cleaner

dirt collection

suction head

suction inlet

suction

suction outlet

filtering device

filter

suction

Electric motor means

suction unit

electric motor

fan

exhaust vent

suction flow

dirty side

External air valve device

Foreign air valve

valve holder

valve disc

closing spring

filter holder

stop spring

Side opening

clean side

electromagnet

annulus

guide sleeve

iron plate front edge

 control device

 battery

 battery

 flap

 button

 Lochplattenresonator

 chamber

 chamber wall

 chamber space

 perforated plate

 cover wall

 First page

 Second page

 First transverse wall

 Second transverse wall

 First longitudinal wall

 Second longitudinal wall

 wall

 opening

 channel

 extension direction

 Sound absorbing material

high pressure cleaner

 discharge device

 pump

 Lochplattenresonator

 perforated plate

 housing

 housing

 chamber

 chamber wall

 chamber space

Claims

claims A cleaning apparatus comprising at least one noise source (33; 120) having a noise emission in a frequency range below 2000 Hz and at least one orifice plate resonator (84; 122) associated with said at least one noise source (33; 120), said at least one A perforated plate resonator (84; 122) has a chamber (85; 129) with a chamber space (88; 132) and a chamber wall (86; 130) and at least one perforated plate (90; 124) covering the chamber space (88; 132) and wherein the at least one perforated plate (90; 124) is acoustically connected to the at least one noise source (33; 120). 2. Cleaning device according to claim 1, characterized in that the at least one perforated plate (90) on the chamber wall (86) is arranged and in particular a wall (106) of the chamber wall (86) on the perforated plate (90) is supported. 3. Cleaning device according to claim 1 or 2, characterized in that the at least one perforated plate (90) of the at least one perforated plate resonator (84) has a first side (94) which faces the chamber space (88), and a second side (96 ) facing the first side (94), wherein a plurality of openings (108) are provided in the at least one orifice plate (90) which are continuous between the first side (94) and the second side (96). 4. Cleaning device according to claim 3, characterized in that the first side (94) and / or the second side (96) are planar. 5. Cleaning device according to claim 3 or 4, characterized in that the first side (94) and the second side (96) are parallel to each other. 6. Cleaning device according to one of claims 3 to 5, characterized in that the openings (108) on the first side (94) in the chamber space (88; 132) open and on the second side (96) of the at least one noise source (33 120) are facing. 7. Cleaning device according to claim 6, characterized in that the openings (108) on the second side (96) open into a channel (110), which is acoustically connected to the at least one noise source (33, 120). 8. Cleaning device according to one of the preceding claims, characterized by at least one sound-conducting channel (110), which leads from the at least one noise source (33; 120) to the at least one perforated plate (90; 124). 9. Cleaning device according to one of the preceding claims, characterized in that the at least one perforated plate (124) forms a housing (126), within which the at least one noise source (120) is arranged. 10. Cleaning device according to claim 9, characterized in that the chamber wall (130) of the at least one perforated plate resonator (122) at least partially forms a housing wall (128) of the cleaning device. 11. Cleaning device according to one of the preceding claims, characterized in that the chamber wall (86) has a cover wall (92) which faces the at least one perforated plate (90), and a wall (106) which between the top wall (92) and the at least one perforated plate (90) is located. 12. Cleaning device according to claim 11, characterized in that the at least one perforated plate (90) and the cover wall (92) are aligned parallel. 13. Cleaning device according to one of the preceding claims, characterized in that the chamber space (88) has a (hollow) cuboid shape. 14. Cleaning device according to one of the preceding claims, characterized in that the chamber wall (86) has a first transverse wall (98), a second transverse wall (100), a first longitudinal wall (102), a second longitudinal wall (104) and a top wall (92 ), wherein the first transverse wall (98) and the second transverse wall (100) are spaced apart and assign each other, the first longitudinal wall (102) and the second longitudinal wall (104) are spaced apart and assign to each other, the first transverse wall (98) and the first longitudinal wall (102) being oriented transversely to one another and the top wall (92) being oriented transversely to the first transverse wall (98), the second transverse wall (100), the first longitudinal wall (102) and the second longitudinal wall (104). 15. Cleaning device according to claim 14, characterized in that the first transverse wall (98) and the second transverse wall (100) are oriented parallel and / or the first longitudinal wall (102) and the second longitudinal wall (104) are oriented in parallel. 16. Cleaning device according to one of the preceding claims, characterized in that the chamber wall (86; 130) is at least partially made of a reverberant material. 17. Cleaning device according to one of the preceding claims, characterized in that in the chamber space (88; 132) at least partially a sound absorption material (114) is arranged. 18. Cleaning device according to one of the preceding claims, characterized in that the at least one noise source (33; 120) has a noise emission in a frequency range below 1000 Hz. 19. Cleaning device according to one of the preceding claims, characterized in that the at least one noise source (33) generates pops. 20. Cleaning device according to claim 18 or 19, characterized in that the at least one perforated plate resonator (84; 122) with respect to geometrical dimensions and arrangement and formation of openings (108) in the at least one perforated plate (90; 124) with respect to the at least one noise source ( 33, 120) is dimensioned such that a noise reduction in the maximum level of at least 2.5 dB takes place through the at least one perforated plate resonator. 21. Cleaning device according to one of the preceding claims, characterized in that the at least one noise source (33; 120) noises due to a pressure change in particular greater than 50 mbar and in particular produced in a period less than 0.05 s. 22. Cleaning device according to one of the preceding claims, characterized by a design as a sucker (10). 23. Cleaning device according to claim 22, characterized in that the sucker has a suction unit (26), a dirt collecting container (12) and a filter device (21), wherein the dirt collecting container (12) via the filter device (21) with the suction unit (26). is in flow communication, and the sucker (10) has a Abreinigungs- device (33) for the filter device (21), wherein the at least one perforated plate resonator (84) of the cleaning device (33) is associated. 24. Cleaning device according to claim 23, characterized in that the cleaning device comprises an external air valve device (33). 25. Cleaning device according to claim 23 or 24, characterized in that the at least one perforated plate resonator (84) with the at least one perforated plate (90) of the cleaning device (33) is arranged opposite one another. 26. Cleaning device according to one of claims 1 to 21, characterized by a discharge device (118) for a cleaning fluid, which comprises at least one pump (120), wherein the at least one perforated plate resonator (122) of the at least one pump (120) is associated. 27. Cleaning device according to claim 26, characterized in that the at least one perforated plate (124) einhaust the at least one pump (120). 28. Use of a perforated plate resonator (84; 122) for noise reduction on a cleaning device (10) which comprises at least one noise source (33; 120) which generates noises in a frequency range below 2,000 Hz. 29. A method for noise reduction in a cleaning device, which comprises a noise source (33; 120) which generates noise in a frequency range below 2000 Hz, in which a sound-active connection between the at least one noise source (33; 120) and at least one perforated plate ( 90; 124) of at least one perforated plate resonator (84; 122) is or will be made.