ES2549114T3 - Vaccum cleaner - Google Patents

Abstract

Vacuum cleaner (1, 200) that includes a frame, inside which is housed an electric motor (240, 340) associated with a fan that allows creating, in operation, suction of air from a tube, upstream of the motor, terminated by a suction unit, up to an air outlet (320) of the frame located downstream of the motor (240, 340), a filtering device being arranged on the air path, preferably upstream of the motor (240, 340), being arranged the engine (240, 340) in a specific fairing (130, 260, 360), characterized in that this fairing (130, 260, 360) is perforated by a plurality of air exhaust openings (132, 262, 362), representing a total area of at least 10 cm2, each opening (132, 262, 362) of the fairing (130, 260, 360) presenting a surface between 0.75 mm2 and 40 mm2 and the openings (132, 262, 362) of the fairing (130, 260, 360) are provided on one or more walls of the fairing (130, 260, 360) which located on the opposite side of the air outlet (320) of the vacuum cleaner frame.

Description

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DESCRIPTION

Vaccum cleaner

The invention relates to the home appliance domain of vacuum cleaners and more particularly to the structure of a vacuum cleaner.

The present invention aims to present a device to reduce the noise attached to the operation of the vacuum cleaner. Numerous documents address this problem, proposing in particular solutions of confinement of the engine, associated or not with an elongation of the air path from the engine to the outlet openings provided in the vacuum cleaner frame. EP 1665972 A1, DE 3402603A1 and WO 97/41631 give examples for noise reduction. Thus, EP 0345699 presents an elongation of the air path after the engine with the help of chicanes. However, such a device is bulky and therefore cumbersome.

The present invention thus proposes a device for noise reduction in a vacuum cleaner according to claim 1. Said vacuum cleaner including a frame, in which an electric motor associated with a fan is housed that allows to create, in operation, an air intake from a pipe, upstream of the engine, terminated by a suction pump, to an air outlet of the frame located downstream of the engine, a filtration device being arranged on the air path, preferably upstream of the engine, the latter being arranged in a specific fairing. According to the invention, this fairing is perforated by a plurality of air exhaust openings, representing a total area of at least 10 cm2, each fairing opening having a surface between 0.75 mm2 and 40 mm2.

Thus, on the one hand the fairing allows, by means of the screen thus constituted, to limit the noise. On the other hand, the realization of a multitude of openings makes it possible to distribute the air flow at the motor outlet, thus preventing it from concentrating in certain privileged areas, a frequent situation when the opening is unique, and which entails locally high speeds and noise consistent step.

This new distribution of the flow is conducive to decrease the higher air velocities by unifying the air velocities over the entire perforated surface, thus entailing a decrease in noise.

However, it is necessary to ensure that the total opening represented by the multitude of openings is significant, at the same time making openings of appropriate section, neither too weak which would generate whistling noise and significant load losses, nor too important, that would not allow Distribute the flow. Thus, the openings represent a total area of at least 10 cm2. On the other hand, the fairing openings each have a surface area between 0.75 mm2 and 40 mm2.

Indeed, it is the association of the two parameters that are the size of the openings and their number, that is, the total surface area of the openings, which provides the best acoustic effect:

-The size of the openings must be adapted so as not to induce whistling noise (when the size is

too small) while allowing a homogeneous distribution of air reducing the

speed variations, due to the significant number of openings, which allows to reduce turbulence,

-the total surface of the openings must be high enough not to induce a loss of loads too large.

The fairing openings are provided in one or more fairing walls located on the opposite side of the air outlet of the vacuum cleaner frame, thus allowing the noise to be transmitted directly to the exit without specific duct or supplementary part.

In order to further improve noise reduction, an absorbent material may be provided in front of the fairing openings, outside said fairing. This material, according to its nature and its dimensions, will absorb a part of the acoustic energy that comes from these openings at certain frequencies and with a certain level of efficiency.

Care will then be taken to size the surface of this absorbent material in front of the openings according to the size of the walls that include said openings, so that the piece thus made is present in front of each of the openings, which increases the efficiency of sound absorption.

On the other hand, the air velocities at the exit of the fairing are not the same according to the position of the opening, this fluctuation depending on the engine's air outlet configuration with respect to the fairing outlet openings, as well as the air outlet position of the vacuum cleaner frame.

In order to reduce the dispersion of the air velocities at the outlet of the fairing, the air passage section downstream of a fairing opening, and defined by the fairing wall and the absorbent material, is all the more important the more Next is the air outlet of the vacuum frame of said opening.

In other words, the air passage section downstream of the fairing outlet openings, which eventually includes an absorbent material, has an increasing air passage section according to the direction of the water flow.

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below the fairing exit openings. In this way, the air passage section thus constituted allows to obtain a more uniform air velocity.

This section increase is advantageously proportional to the section increase generated by the fairing outlet openings found in the air path, in order to maintain a uniform air velocity between the air velocity at the level of the fairing outlet openings and The air velocity in this section of air passage just downstream of these openings.

In particular, the air passage section in the vicinity of an opening is all the more important the closer the air outlet opening of the vacuum frame is, in order to reduce the air velocity in this air passage section. with respect to the air velocity at the level of the fairing outlet openings.

Advantageously, the absorbent material used is a foam, whose pore density is preferably greater than 75 pores per inch.

On the other hand, in order to increase the noise reduction, a supplementary soundproofing fairing in which the part of the fairing including the openings, as well as the absorbent material, are arranged can be provided in one of the improvements of the invention.

According to a preferred mode of implementation of the invention, at least one of the fairings is made of polypropylene, the frame may be made, essentially, of expanded polypropylene (PPE).

The use and advantages associated with expanded polypropylene for the realization of at least a part of the vacuum cleaner frame have been described in patent application FR 2873563.

The advantages of the realization of the body of the apparatus of this matter are numerous: lightness, respect for the environment, robustness. However, by performing the body of the vacuum cleaner, or a part of the body of the vacuum cleaner, of PPE, the expanded nature of the material can allow the body to be pierced with a tip. If such an operation takes place, for example, during a collision with a metal rod, such as a knitting needle, it is necessary to prevent the latter from coming into contact with the electrically active parts that constitute the electrical connections of the motor.

It should be noted that said accident has no consequences on the robustness of the body of the apparatus, allowing the plasticity of the PPE to the material to recover its shape after the object is removed without real damage to the structure.

Thus, the motor fairing, in addition to the acoustic properties described above, allows the active parts of the motor to be protected by surrounding them with a specific protection of a rigid material. Rigid material means a material resistant to mechanical stresses, however, this resistance can cause a certain deformation of the material, in particular a material that passes standard 60-335-1 Art. 30 in relation to standard IEC 60- 695-10-2, which provides for a resistance test to the penetration of a ball with a diameter of 2.5 mm under a force of 20 Newton, which must leave a mark of less than 2 mm.

Preferably, the hardness of this material is greater than or equal to 5 Hv. Polypropylene (PP) will be advantageously used for the realization of the fairing.

The use of PP and PPE also allows reducing the diversity of the plastic materials used and facilitates the recycling of the device at the end of life.

Other features and advantages of the invention will be given by the following description, with reference to the attached figures that constitute only non-limiting examples of embodiment. Figs. 1 to 4 represent a first mode of implementation of the invention, while fig. 5 to 11 illustrate a second mode of implementation of the invention.

Fig. 1 is a perspective view of a vacuum cleaner provided with the present invention.

Fig. 2 is an exploded view of the different main parts of the vacuum cleaner.

Fig. 3 is an orderly exploded view, from below and in perspective, of certain parts of the vacuum cleaner.

Fig. 4 is an exploded view, in perspective, of the fairing of the vacuum motor.

Fig. 5 is partial cutting of the frame of a vacuum cleaner in a second implementation of the invention.

Fig. 6 is a rear perspective view of the vacuum cleaner.

Fig. 7 is a top view of the vacuum cleaner.

Fig. 8 is a sectional view according to section A-A of fig. 7.

Figs. 9 and 10 are, respectively, a side and rear view of a detail of the invention.

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Fig. 11 is an exploded view of a subset of the vacuum cleaner.

Figs. 12 and 13 represent variants of embodiment of this second implementation of the invention, respectively in perspective views and in section of certain elements of the vacuum cleaner.

As figs. 1 to 3, the vacuum cleaner 1, according to a first mode of implementation of the invention, is constituted by a vacuum cleaner body composed of three main parts manufactured separately and then assembled below:

• a small lower body 2 that has:

◦ of a housing 20 of the bottom of the engine,

◦

of a location 22 for the subsequent maneuvering organs such as wheels or roulette wheels (not 10 shown),

◦

of an air outlet 26 of the vacuum cleaner,

◦

of a housing 30 from the bottom of an electric cable reel 10,

• an upper body 4 comprising:

◦

a space 40 provided for the reception of a bag of filter dust, 15 ° a housing 42 of the upper part of the electric cable reel 10,

◦

a location 48 for the front operating elements (not shown) of the vacuum cleaner,

◦

a housing drain 44 of the upper part of the engine, together with the housing 20 of the lower body 2,

◦

an insert 45 that allows the connection of the suction tubes, this insert cooperating with a bag holder 46 arranged in the space 40.

• a rear part 50 that includes a large handle 52 for transporting the vacuum cleaner.

According to the first example of implementation of the invention, the constituent material of the vacuum cleaner, therefore, is at least the upper body 4, and preferably also the lower body 2 and the rear piece 50, is made of expanded polypropylene (PPE).

25 However, in order to reinforce the impact resistance of the handle 52, the rear piece 50 has an unexpanded PP core that allows the piece 50 to be able to mechanically resist an eventual violent shock on said handle.

The weak mechanical resistance of the PPE has, however, a need to considerably increase the thicknesses of the walls in order to have sufficient strength. However, and surprisingly, even if the volume of material required then involves a more bulky vacuum than normal, the mass of plastic material can be

30 reduced strongly, and the final weight of the vacuum cleaner can be divided by two.

However, the amount of material remains smaller than a traditional vacuum cleaner, which is equally advantageous from an economic point of view since the vacuum cleaner is less expensive to manufacture.

The great flexibility of the PPE allows an improved absorption of the shocks with respect to the other plastics traditionally used to manufacture the vacuum cleaners. To this great flexibility is associated, according to the degree of expansion, a

The elastic memory of the material, which also presents important advantages in terms of assembling the different complementary pieces fitted on the body of the apparatus. Indeed, it is thus possible to articulate, for example, the different caps without hinge and block them simply by deforming the material. This curious feature also allows you to fix inserts, by means of lace, without difficulty.

Indeed, it is enough to "force" the material to be deformed to block or fix an insert, the material recovering its shape after deformation to maintain the assembly.

Thus, according to the proposed example, a cover 80 is made of expanded polypropylene and is disposed on the upper body. The mechanical resistance of the cover on the upper body 4 of the vacuum cleaner is obtained by fitting, deforming the material, as explained above.

This lid allows the dust bag housing to close and allows the air coming out of the bag to the

45 engine block As an accessory, this cover can receive, in its thickness, different suction accessories such as a small brush, a suction nozzle, etc.

According to the proposed example, the maintenance of the upper body on the lower body is ensured by rods 12,

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13 that rest under the lower body 2. The rods 12 come into contact with the rear piece 50, while the rod 13 is connected to a rigid piece 90 arranged on the upper body 4.

The supports of the rods 12 and 13 under the lower body 2 are preferably associated with the roulette wheels, not shown, of the vacuum cleaner. As regards the central roulette, the latter is associated with a platform 11 that allows to re-center the roulette with respect to the whole of the vacuum cleaner.

The proper assembly of the upper body on the lower body consists, according to the example presented, in threading the rods 12 and 13 into corresponding tubes out of the pieces 90 and 50, advantageously crossing the tubes and / or the rods, a part of the body top 4. Fig. 2 shows in particular such tube 14 coming out of the piece 90, this tube receiving the rod 13 that crosses the lower body 2 through the hole 24.

Threading thus allows the upper body to be compressed by means of parts 90 and 50, allowing the relatively significant deformation of the PPE, as previously described, to seal the lower and upper bodies, without seals. specific.

The rigid piece 90 can have very different shapes and shapes, ranging from a piece that covers substantially the entire width of the upper body, as presented, in the rear part of the dust bag compartment, to a piece with more recesses It is also possible to consider the realization of several independent pieces.

In the same way, and on the contrary, the support surface under the lower body can be secured by a more or less extended plate, as well as to the rigid part 11. It is then possible to arrange a rigid piece under the lower body and points more specific support on the upper body.

The rigid part 90 disposed on the upper body, however, offers the advantage of being able to perform other functions. Thus, the rigid part 90 presents the locations of the on / off control button 60, in relation to a switch, as well as that of the rewind button 68 of the electric cable on the reel 10.

The rigid part 90 also has a housing 92 for a box 94 that encloses a filter with HEPA type folds, which allows the air that comes from the dust bag to be filtered, before entering the engine.

The indicators, control and maneuvering bodies 60, 68, as well as the rigid part 90, the tubes 12, 13 as well as the roulettes, will preferably be made of non-expanded polypropylene.

The electrical circuit for feeding the motor from a domestic outlet begins with the power cord of the vacuum cleaner, mounted on the reel 10. Electrical wires leave the fixed part of the reel to connect to two terminals 72 of an electronic card 70. Two others terminals 72 of the electronic board 70 are used for connection with the on / off button. Finally, two other terminals 72 allow the motor to be connected to the electrical circuit.

According to this exemplary embodiment, the vacuum cleaner 1 includes protections of the active parts of the apparatus, that is, of the electrical connections of the different elements of the motor supply circuit.

Thus, the reel 10 includes a crankcase 100 that covers the rear of the reel. This crankcase thus covers the connection of the electric wires at the level of the winder.

On the other hand, the engine, not shown, is, according to the invention, contained in a crankcase 120 whose cover 122 has a chimney 124. The crankcase 120 is advantageously constituted by rigid pieces made of unexpanded polypropylene.

The cover 122 has, on the other hand, air inlet holes 126, as well as a seal 128, which allows to ensure the tightness of the engine fairing during compression of the lower and upper bodies.

The chimney 124 fully receives the electronic card 70. Thus, the power supply wires that come from the winder connect two of the terminals 72 of the electronic card where they are connected to said card.

The crankcase 120 also includes a substantially cylindrical fairing 130, which surrounds the engine and on which the cover 122 is fixed by a bayonet type assembly. This fairing, in association with the chimney 124, protects the terminals 72 as well as the moving parts of the motor. It also allows to confine the noise generated by the engine.

For this purpose, the fairing advantageously includes a multitude of air escape openings 132, these openings having a cylindrical shape having a diameter of the order of 2.5 mm. According to the proposed example, the fairing comprises more than 400 openings, which represent a total output area close to 21 cm2.

In order to further reduce the noise generated by the engine, a foam 134 is arranged in front of the openings 132, this foam resting against one of the substantially vertical faces of the upper body 4. Such foam allows to absorb the impact noise of the air against the vertical wall of the upper body, before reaching the outlet 26 of the lower body 2.

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As is well visible in fig. 4, the round shape of the fairing and the associated foam allows limiting the impact noise of the air and fluidizes the air flow at the fairing outlet.

This outlet is advantageously carried out on the opposite side of the openings 132, in order to lengthen the air circuit, which is favorable to the reduction of noise. An improvement of this acoustic decrease is also to provide a foam 136 in a support 138, in front of the air outlet 26, as shown in fig. Four.

Advantageously, the fairings and protective boxes are made of non-expanded polypropylene in order to limit the diversity of the materials used. However, in the context of the invention, it can be considered to use another material that has the required qualities of electrical insulation and good mechanical strength, in particular resistance to penetration of a tip.

As regards expanded polypropylene, it will be used with degrees of expansion defined by the amount of material (polypropylene) per liter. Content between 40 g and 80 g of material per liter will be used in a privileged manner.

On the other hand, in order to facilitate the recycling of the polypropylene used, the use of homopolymers will be favored.

According to a second example of implementation of the invention, as shown in figs. 5 to 11, the vacuum cleaner 200 comprises a frame consisting essentially of an upper body 202 and a lower body. For reasons of valuation of the invention, the lower body has not been represented.

The upper body 202 has a power inverter 210, as well as two buttons 212 and 214 that allow, respectively, to rewind the motor power cord and start or stop the vacuum motor.

The rounded part in the front part of the upper body is configured in a handle 218. A lid 215 is articulated on the upper face of the body 202 which carries the connection 216 of a suction tube, not shown.

The upper body includes, on the other hand, a compartment 206 of the air filtration and storage bag of the sucked debris, said compartment being closed, in the upper part, by the lid 215. The compartment 206 includes, on its face rear 207, air communication openings with the engine compartment.

The upper body 202 also carries the front roulette 230, as well as the rear roulette wheels (not shown), and the thread passer 222 which allows the power supply cord to be guided towards the winder.

According to the invention, the engine 240 is arranged in a fairing comprising two parts: a high part 250 that covers the air inlet of the engine, and a low part 260 that covers the air outlet of the engine, as illustrated in fig.

8. Therefore the fairing completely surrounds the engine and thus reduces the noise from the confinement thus generated.

Fig. 11 shows the arrangement of the motor in the fairing. A gasket 242 allows the air inlet seal of the engine inside the fairing, while a gasket 252 allows the air connection between the compartment 206 containing the waste bag, and the engine area to be sealed.

In addition, a gasket 254 ensures the tightness between the two parts of the fairing.

On the other hand, the lower part 260 of the fairing is perforated by a multitude of openings 262 that allow the air to exit the fairing. Opposite these openings is an absorbent element 270, such as a foam. This foam is arranged substantially along the entire air path from the fairing outlet to the vacuum frame outlet, this output being made through a HEPA type filter 220.

Advantageously, and as shown in figs. 8 and 11, the lower fairing 260 of the engine, as well as the foam 270 and the HEPA filter 220 are arranged in a support 280 which is fixed on the upper fairing 250, said support thus constituting a second fairing, which, by the wall presented, allows to reduce more the noise perceived outside the device.

The size and number of openings 262 are substantially those indicated above. These openings are advantageously arranged according to a network, as is well visible in fig. 10, whose horizontal pitch p is of the order of 6 mm and whose vertical pitch q is about 3.5 mm. However, a variable can be considered according to the relative position of the openings with respect to the air outlet of the vacuum cleaner frame.

On the other hand, the thickness e of the fairing 260 at the level of the openings is of the order of 4 mm, allowing this consequent thickness to make a laminar flow at the exit of the fairing. In addition, this thickness is sufficient to conceive, in one of the improvements of the invention, truncated conical openings, that is, they widen from the inside to the outside of the fairing, allowing these openings, by their nozzle shape, to reduce the exit speeds of air.

According to an improvement of the invention, these openings are located on the rear and inner faces of the lower part of the fairing, that is, on the opposite side of the air outlet opening of the frame of the apparatus, being made

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this output through filter 220.

In operation, the air, after having passed through the filter bag and then the engine, exits the latter according to the arrow indicated in fig. 8. Next, it leaves the fairing through the openings 262 before going along the absorbent element 270 and then exiting the frame through the filter 220.

As is well visible in figs. 8 and 9, the air passage section, on the height a of the walls of the fairing 260 is smaller for the openings that are far from the air outlet of the frame of the apparatus, in order to compensate the air outlet velocities , weaker through these openings.

Thus, the passage section S1 is smaller than the passage section S2, thus allowing the air flow to be distributed substantially over the entire width of the bored area of the fairing.

This section evolution is carried out by a curvature 272 given to the foam 270, which allows a progressive and linear evolution conducive to limit turbulence and impact noise.

This more homogeneous distribution of the air flow at the exit of this fairing thus contributes to the reduction of air circulation noise.

Figs. 12 and 13 present a variant embodiment of the motor fairing in this second implementation of the invention.

Thus, fig. 12 presents the lower part 360 of an engine fairing, this lower part presenting openings 362 whose dimension, number and need are substantially the same as those described above. However, the openings 362 are positioned only on the lower wall of the lower part of the fairing, on the opposite side of the air outlet 320 of the vacuum cleaner frame, as shown in fig. 13 representing a sectional view of the engine and associated fairings.

Thus, the motor 340 is housed in a fairing composed of a high part 350 and a low part 360. The air outlet openings 362 of the fairing allow air to be directed downwards. An absorbent material 370, as described above, is arranged in front of the openings, outside the fairing, in order to absorb a portion of the acoustic energy from the outgoing air flow. This material is contained in a second fairing 380 fixed to the upper part 380 of the first fairing.

As can be seen in fig. 13, the section of air passage at the exit of the lower part 360 of the fairing is increasing in the direction of the air flow, in order to distribute the air flows through said openings, and to limit the velocity dispersions of air at this level.

The present invention is not limited to the two proposed implementation examples and the aforementioned improvements, but also encompasses all the technical equivalents of the solutions considered.

Claims (9)

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one.

Vacuum cleaner (1, 200) that includes a frame, inside which an electric motor (240, 340) is associated with a fan that allows to create, in operation, air suction from a tube, upstream of the engine, terminated by a sucker, to an air outlet (320) of the frame located downstream of the engine (240, 340), a filtering device being arranged on the air path, preferably upstream of the engine (240, 340), being arranged the engine (240, 340) in a specific fairing (130, 260, 360), characterized in that this fairing (130, 260, 360) is perforated by a plurality of air exhaust openings (132, 262, 362), representing a total area of at least 10 cm2, each opening (132, 262, 362) of the fairing (130, 260, 360) having an area between 0.75 mm2 and 40 mm2 and the openings (132, 262, 362) of the fairing (130, 260, 360) are provided on one or several fairing walls (130, 260, 3 60) located on the opposite side of the air outlet (320) of the vacuum cleaner frame.

2.

Vacuum cleaner (1, 200) according to one of the preceding claims, characterized in that an absorbent material (134, 270, 370) is arranged in front of the openings (132, 262, 362) of the fairing (130, 260, 360), in the outside of said fairing.

3.

Vacuum cleaner (1, 200) according to one of the preceding claims, characterized in that the surface of the absorbent material (134, 270, 370) in front of the openings (132, 262, 362) is at least equal to the surface of the or the fairing walls (130, 260, 360) that include the openings (132, 262, 362).

Four.

Vacuum cleaner (200) according to one of claims 2 or 3, characterized in that the absorbent material (270, 370) is disposed at a variable distance from the or of the fairing walls (260, 360) including the openings (262, 362).

5.

Vacuum cleaner (200) according to the preceding claim, characterized in that the air passage section (S1, S2) downstream of an opening (262, 362) of the fairing (260, 360), is defined by the fairing wall (260 , 360) and the absorbent material (270, 370), is all the more important the closer the air outlet (320) of the vacuum frame of said opening (262, 362).

6.

Vacuum cleaner (1, 200) according to one of claims 2 to 5, characterized in that the absorbent material (134, 270, 370) is a foam.

7.

Vacuum cleaner (200) according to one of claims 2 to 6, characterized in that the part of the fairing (260, 360) that includes the openings (262, 362), as well as the absorbent material (270, 370), are arranged in a Soundproofing fairing (280, 380).

8.

Vacuum cleaner (1,200) according to one of the preceding claims, characterized in that at least one of the fairings (130, 260, 360) is made of polypropylene.

9.

Vacuum cleaner (1, 200) according to one of the preceding claims, characterized in that the frame is made essentially of expanded polypropylene.

8