FR2770624A1 - FRAGMENT TYPE MUFFLER - Google Patents

Abstract

The present invention relates to a fragmented type silencer characterized in that several modular elements are associated longitudinally to form the length closest to the desired length and several modular elements are superimposed to approach the height closest to the height of the duct.

Description

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Fragmented type silencer

  The present invention relates to a fragmented type silencer.

  To reduce the noise generated by the movement of air in a ventilation duct, it is known to use fragmented type silencers. A fragmented type silencer is made of glass wool or rock wool panels fixed parallel to the vertical plane containing the axis of symmetry of the ventilation duct. These insulating panels have a length determined by the degree of sound attenuation desired. The silencers are adapted to the particularity of each building and to the desired ventilation power. They therefore have, for each embodiment, a different section so that the height of each panel of insulating material must be cut "to measure". Consequently, it is not possible to manufacture in

series this type of muffler.

  The present invention therefore aims to overcome the drawbacks of the prior art by proposing a silencer of the fragmented type adaptable to

length and height.

  This object is achieved by the fact that the fragmented type silencer consists of several modular elements associated longitudinally to form the length closest to the desired length; and stacked vertically to approach the height closest to the height of the duct

  with a maximum difference of 69 mm for the height.

  According to another feature of the invention, the modular elements are juxtaposed one behind the other in a U-shaped rail; fixing tabs being located at the ends of said rail, for retaining the elements

modular to each other.

  According to another feature of the invention, each modular element is formed of a frame having substantially the shape of a rectangular parallelepiped, and of two insulating panels held vertically and spaced apart,

  parallel to the plane containing the axis of the ventilation duct.

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  According to another feature of the invention, at least one insulating panel is held at the level of the upper part of the frame of an element

  modular, parallel to the plane containing the axis of the ventilation duct.

  According to another feature of the invention, between the two insulating panels an air channel is arranged to allow better absorption of air while reducing the amount of absorbent material required. Indeed, by this device, the same sound attenuation is obtained with approximately 20%

less insulation material.

  According to another particular feature of the invention, the frame of the modular element 0io is metallic and pierced with holes on at least the part of the rounded faces arranged opposite the space between the insulating panels for

allow the passage of air.

  According to another feature of the invention, the frame of the modular element is metallic and pierced with holes on these flat faces to allow

  is better absorption of low frequencies.

  According to another feature of the invention, the vertical faces of the frame of the modular element extend perpendicular to their generatrix

  to form a horizontal rim on the surface of said frame.

  According to another feature of the invention, two of the parallel faces of the modular element are rounded so that several modular elements juxtaposed one behind the other fit together along the axis

  of the ventilation duct and incorporates a leak and attack nozzle.

  According to another feature of the invention, each insulating panel is held at the edge of the frame, at spacers and along the sides of the faces

of the frame.

  According to another characteristic of the invention, the spacers connecting two parallel faces of the frame are stamped in a U at their center in order to

  consolidate the space forming the airway.

  According to another feature of the invention, each modular element comprises means for fixing and assembling the modular elements the

to each other.

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  According to another feature of the invention, the means for fixing and assembling the modular elements on top of each other comprise at least one boss in the upper part of the frame and its housing

  complementary in the lower part of the frame.

  According to another feature of the invention, the means for fixing and assembling the modular elements one on top of the other comprise at least one tongue in the upper part of the frame and a perforated pin in the lower part of the frame, said tongue penetrating in the perforation

  said tenon to secure the two modular elements.

  According to another feature of the invention, the air path has a thickness

30 mm.

  Other features and advantages of the present invention

  will appear more clearly on reading the description below made in

  reference to the accompanying drawings in which: - Figure 1 shows a perspective view of a modular element comprising a first means for vertical fixing of the modular elements; - Figure 2 shows a top view of the modular element; - Figure 3 shows a sectional view along the axis A-A of the modular element comprising a first means for vertical fixing of the modular elements; - Figure 4 shows a sectional view of two elements

  modular, according to Figure 3, vertically nested one on the other.

  - Figure 5 shows in perspective two modular elements fitted longitudinally into one another and fixed on a rail; - Figure 6 shows a sectional view of a sheath with a set of modular elements installed; - Figure 7 shows the air currents around a modular element which does not have an air path; - Figure 8 shows the air currents around a modular element which includes an air channel;

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  - Figure 9 shows a view of a rounded face of a modular element comprising a second means for fixing the modular elements to each other; - Figure 10 shows a view of a flat face of a modular element according to Figure 9; - Figure 11 shows a perspective view of two modular elements, according to Figure 9; - Figure 12 shows a sectional view of two elements

  modular, according to figure 9, fixed vertically one on the other.

  The modular fragmented type silencer according to the invention is

  consisting of several modular elements fixed to each other.

  Figure 1 shows a perspective view of a modular element.

  It is formed by a frame (1) having substantially the shape of a rectangular parallelepiped s15. The four vertical faces of this frame (1) extend perpendicular to their generatrix to form a horizontal edge (2) on the upper surface of the frame (1) (Figure 2). The two parallel faces of smaller width are rounded. Thus, a first end (9) of the frame (1) has a concave face (10) and a second end of the frame (1), facing it, has a convex face (9). The other two faces (11,12) of the

frame are flat.

  The modular elements are juxtaposed one behind the other on a rail (13) (Figures 5,6). This rail (13) is fixed to the bottom wall of the ventilation duct (14), parallel to the axis of symmetry of the ventilation duct. The convex face (10) of the modular element is oriented facing the

  air flow. The arrow A in FIG. 5 represents the direction of the air flow.

  The convexity of the face (10) allows better penetration of the air through the modular element and eliminates the use of an attack spout, while the concavity of the face (9) associated with the channel d indoor air avoids the use of a

  trailing spout. The shape of the modular element is in no way limiting.

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  The frame of the modular element (1) can be, for example, a metal frame pierced with holes (15) on its rounded faces (9, 10) to allow the passage of air and on these planar faces (11, 12 ) to allow absorption of low frequencies. The holes (15) drilled in the frame (1) are optional s except on the parts facing the airways where they are necessary for

air passage.

  Two panels of insulating material (4) are held in the frame (1) by upper (3) and lower (14) spacers. Each panel (4) has the same length as the frame (1), a thickness less than the half-width io of the frame (1) and a height slightly less than the height of the frame (1) (Figures 1,3). Each insulating panel (4) is fixed against the internal wall of

each of the faces (11,12) of the frame.

  An air channel (5) is provided in each modular element. The air path (5) is arranged in the center of the modular element, vertically, between the two insulating panels (4). It should be noted that the insulating panels and the air channels can be placed horizontally. As shown in Figures 7 and 8, the track (5) facilitates the passage of air and prevents the creation of vortices due to small depressions at the end of the modular elements. In addition, the air path (5) allows additional absorption of the waves at

high frequencies.

  Advantageously, the insulating panels (4) are held by spacers (3,14). The spacers (3,14) connect two vertical faces of the frame (1) facing each other. They can, for example, be riveted to the frame (1). In addition, the spacers (3) can be stamped in a U shape in their center so that, not only do they more securely hold the panels (4) but, in addition, they consolidate the space existing between the two insulating panels, forming the air channel (5). The insulating panel (4) has a height such that when two modular elements are fitted one on the other, the lower spacer (14) supporting the insulating panel (4) of the frame of the first element (la) is resting on the edge (2) of the frame of the second element (lb)

(Figures 4, 12).

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  FIG. 6 represents several modular elements which are juxtaposed one behind the other on a U-shaped rail (13) in order to obtain a silencer of the desired length. Said rail (13) is fixed to the bottom wall of the duct (14). Fixing tabs (8) located at the ends of said rail (13), hold the modular elements together. Thus, even when the air currents are very strong, the modular elements remain linked. (Figures 5,6) The modular elements are stacked on top of each other to obtain a silencer of the desired height. Each modular element comprises means for fixing and assembling the modular elements one on top of the other. According to one embodiment of the invention, the fixing between the different modular elements is carried out by fitting the frames together. The frame (1) is either slightly flared in its lower part or forms a shoulder (Figures 3, 4). Thus, the area of the frame (1) below the insulating panel (4) has an internal width equal to the external width of the upper part of the modular element. The outer surface of the frame (1) has at least one boss (6) in its upper part and its corresponding housing (7) in its lower part. The housings (7) located on the frame of a first element (la) will fit into the boss (6) of the frame of a second element (1b) located below the

first element.

  According to another embodiment of the invention, the modular elements superimposed on each other are fixed by means of pins (17) in the upper part of the frame and tabs (16) in the lower part of the frame (Figures 9 , 10, 11, 12). Each tongue (16) is formed by cutting a puncture (161) in the upper part of the frame (1). The tongues protrude outside the frame (1) so that they are perpendicular to the planar faces (11, 12) of the frame. At least part of the planar lower faces of the frame (11, 12) extends slightly flared in order to form a stud (17). This post (17) is perforated in its lower part with an orifice (171) of dimension allowing the penetration of the

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  tongue (16) in the hole (171) of the post (17). FIG. 11 shows that when a first modular element (la) is placed on a second modular element (lb), the tongue (16) of the second modular element (lb) becomes embedded in the orifice (171) of the tenon (17 ) of the first modular element (la). Figure 12 shows a sectional view of two modular elements assembled one on the other using this fastening means. These methods of fixing elements

  modular on top of each other are in no way limiting.

  The modular elements preferably have a height of 70 or 200 mm; by their combination we can achieve different heights. Thus, the remaining height between the metal or concrete pipe and the modular silencer will be a maximum of 69 mm, this height being insufficient to generate noise. The modular elements preferably have a width of 200 mm, and the insulating fabric a thickness of 85 mm so that the central air channel has a thickness of 30 mm. The thickness of the air channel can vary between 10 and 50 mm, but it is by choosing this value of 30 mm that the

  better results have been observed.

  The modular elements preferably have a length of 300 mm or 500 mm, this allows lengths of 300 mm, 500

  mm, 600 mm, 800 mm, 900 mm, 1000 mm, 1100 mm, 1200 mm ....

  In FIG. 6, four modular elements of 500 mm x 200 mm X mm (length x width x height), two modular elements of 300 mm x 200 mm x 200 mm, two modular elements of 500 mm x 70 mm x 200 mm and a modular element of 300 mm x 70 mm X 200 mm was mounted on a rail (13). The assembly of these modular elements generates a fragmented type silencer with a length approaching the desired length and

  a height approaching the height of the duct (14).

  It is clear that other modifications within the reach of those skilled in the art fall within the scope of the invention; Thus, the insulating panels can equally well be made of glass wool, rock wool, foam

or any other absorbent material.

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Claims (11)

  1. Fragmented type silencer characterized in that several modular elements are associated longitudinally to form the length closest to the desired length and several modular elements are superimposed vertically to approach the height closest to the   height of the duct with a maximum difference of 69 mm for the height.   2. Modular fragmented type silencer according to claim 1 characterized in that the modular elements are juxtaposed one behind the other in a U-shaped rail (13), fixing tabs (8) being located at the ends of said rail (13) , to hold the modular elements together. 3. Modular element intended to be used in a silencer according to   any one of claims 1 or 2 characterized in that each   modular element is formed by a frame (1) having substantially the shape of a rectangular parallelepiped, and two insulating panels (4) held vertically and spaced apart, parallel to the plane containing the axis of the ventilation duct. 4. Modular element according to claim 3 characterized in that at least one insulating panel (4) is held at the upper part of the frame (1) of a modular element, parallel to the plane containing the axis of the ventilation duct.   5. Modular element according to claim 3 characterized in that between two insulating panels (4) an air channel (5) is arranged to allow the passage of air and better absorption of air while   reducing the amount of insulating material required.   6. Modular element according to claim 3 characterized in that the frame (1) of the modular element is metallic and pierced with holes (15) on at least the part of the rounded faces arranged opposite the space between the   insulating panels to allow the passage of air. 9 2770624   7. Modular element according to claim 3 characterized in that the frame (1) of the modular element is metallic and pierced with holes (15) on these planar faces (11, 12) to allow better absorption of low frequencies. 8. Modular element according to claim 3 characterized in that the vertical faces of the frame (1) of the modular element extend perpendicular to their generatrix to form a horizontal flange (2) at the surface of said frame.   9. Modular element intended to be used in a silencer according to   io any one of claims 1 or 2 characterized in that two of   parallel faces of the modular element are rounded so that several modular elements juxtaposed one behind the other fit together along the axis of the ventilation duct and incorporates a spout and a spout.   1 0. Modular element according to claim 3 characterized in that each insulating panel (4) is held at the edge (2) of the frame (1), at   spacers (3, 14) and along the sides of the faces (11, 12) of the frame.   11. Modular element according to claim 10 characterized in that the spacers (3,14) connecting two parallel faces of the frame (1), are stamped   U-shaped in their center to consolidate the space forming the air path (5).   12. Modular element intended to be used in a silencer according to   any one of claims 1 or 2 characterized in that each   modular element comprises means for fixing and assembling the   modular elements to each other.   13. Modular element according to claim 12 characterized in that the means for fixing and assembling the modular elements on top of each other comprise at least one boss (6) in the upper part of the   frame and its complementary housing (7) in the lower part of the frame.   14. Modular element according to claim 12 characterized in that the means for fixing and assembling the modular elements one on 2770624   the others have at least one tongue (16) in the upper part of the frame and a perforated pin (17) in the lower part of the frame, said tongue (16) penetrating into the perforation of said pin (17) to secure the two modular elements.   15. Modular element according to claim 5 characterized in that   the air channel (5) has a thickness of 30 mm.