FR2821660A1 - Acoustic absorption structure for automobile heating unit - Google Patents

Abstract

The acoustic absorption structure (30) for a heating unit (1) is installed in the unit in a zone subjected to strong air turbulence. It is in the shape of a long prismatic foam sleeve. The foam is surrounded by a rigid frame. An Independent claim is included for an automobile heating unit fitted with the acoustic absorber.

Description

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ACOUSTIC ABSORPTION STRUCTURE FOR APPARATUS
HEATING AND / OR AIR CONDITIONING,
AND APPARATUS HAVING SUCH A STRUCTURE.

 The invention relates to a sound absorption structure for heating and / or air conditioning apparatus, in particular of a passenger compartment of a motor vehicle, as well as the apparatus equipped with said structure.

 Current heating and / or air conditioning devices for the passenger compartment of a motor vehicle are noisy due to the vibration of the parts of these devices and the circulation of air. This causes discomfort for the comfort of the occupants, in particular for communication, and this can lead to increased fatigue and a decrease in the driver's attention.

 A solution to this problem has already been proposed and consists in fixing a sound absorbing material, in particular by overmolding the parts using a foam or by bonding this material.

 However, these solutions are not satisfactory, due to the dimensions and the complexity of the shapes of the parts to be soundproofed, a low level of reliability and quality of soundproofing being obtained.

 The object of the invention is to solve at least one of the problems mentioned above.

 To do this, the invention provides an absorbent structure reversibly placed at the source of the acoustic disturbances.

 More specifically, the object of the invention relates to a sound absorption structure for a heating and / or air conditioning device, in particular for a passenger compartment of a motor vehicle, said structure being of a shape suitable for being removably mounted in the minus an area of the device subject to strong air turbulence.

 Under these conditions, the sound power level is significantly reduced by stopping the propagation and internal acoustic amplifications.

 According to a particular embodiment, the structure is in the form of an elongated foam sleeve of prismatic shape, which can be surrounded by a perforated rigid frame to facilitate its immobilization. The frame can be composed of a grid of plastic material molded in the shape of an openwork drawer, provided with releasable fixing means.

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- la structure d'absorption acoustique est montée en regard d'un volet d'une conduite de circulation d'air ; - la structure d'absorption acoustique est montée sur un volet d'une conduite de circulation d'air ; - la structure d'absorption acoustique est montée le long d'une paroi d'une conduite de circulation d'air. According to particular embodiments: - the sound absorption structure is mounted inside the air propulsion member, along at least one part of the wall of the volute; - The sound absorption structure is mounted on the air propulsion member, in the convex part formed by the volute nozzle;

- The sound absorption structure is mounted opposite a flap of an air circulation pipe; - the sound absorption structure is mounted on a flap of an air circulation pipe; - The sound absorption structure is mounted along a wall of an air circulation pipe.

 The invention also relates to a heating and / or air conditioning device, in particular for a passenger compartment of a motor vehicle, said device comprising at least: - an external chassis forming a pipe for circulation of hot and / or cold air in direction of ancillary pipes, - an air propulsion member mounted in the chassis, - a means of heating and / or cooling of the expelled air mounted in the chassis, - at least one deflection flap and / or sealing said air flow mounted in the chassis, and - an acoustic absorption structure mounted in the chassis.

 The sound absorption structure defined above is mounted in this device.

 Other characteristics, details and advantages of the invention will emerge on reading the description made with reference to the accompanying drawings given by way of example and in which: - Figure 1 is a schematic sectional view of a portion d an air conditioning unit for the passenger compartment of a motor vehicle according to the invention; - Figure 2 is a detailed perspective view of the air circulation pipe belonging to the air conditioning apparatus of Figure 1;

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 - Figure 3 is a detailed perspective view of a volute of an air propulsion member belonging to the air conditioning unit of Figure 1 and comprising an acoustic absorption structure at the volute nozzle; FIG. 4 is a detailed exploded perspective view of a scroll of an air propulsion member belonging to the air conditioning apparatus of FIG. 1 and comprising a structure for sound absorption on the internal surfaces; and - Figure 5 is a detailed perspective view of an air circulation pipe belonging to the air conditioning apparatus of Figure 1 and comprising a sound absorption structure.

 A portion of air conditioning device 1 for the passenger compartment of a motor vehicle is shown diagrammatically in section and in perspective in FIGS. 1 and 2. This portion comprises an external chassis 10, for example made of plastic, having an upstream portion 12 typically connected to a vehicle bulkhead (not shown) and a downstream part 14 divided, in this case, into a front pipe 16 and a rear pipe 18.

évaporateur 22 et un radiateur 24, sont montés successivement dans le châssis 1 D, l'évaporateur 22 étant monté en amont du radiateur 24 et en aval du pulseur 20, selon le sens de circulation de l'air illustré par la flèche F. An air propulsion member 20, a blower, and a

evaporator 22 and a radiator 24, are successively mounted in the frame 1 D, the evaporator 22 being mounted upstream of the radiator 24 and downstream of the blower 20, according to the direction of air circulation illustrated by the arrow F.

 Flaps for dividing the flow of hot and / or cold air as well as shutters for closing certain conduits can also take place in the apparatus 1. A single flap 26 for dividing the flow of fresh air, movable according to the arrows G around an axis A, is illustrated in this case.

 An acoustic absorption foam 30, for example made of polyurethane, is removably mounted opposite the flap 26. The foam has a prism shape and is mounted by any releasable means: repositionable adhesive, retractable zipper, clipping, etc.

d'une portée et montée de manière amovible sur le châssis 10 de l'appareil 1. Cette structure insonorisante 30 minimise également la propagation et l'amplification des bruits de turbulences au sein de l'appareil de climatisation1 pour éviter de les transmettre à l'habitacle. The flap 26 for dividing the fresh air is thus placed opposite

of a range and removably mounted on the chassis 10 of the device 1. This sound-absorbing structure 30 also minimizes the propagation and amplification of the turbulence noises within the air conditioning device1 to avoid transmitting them to the cabin.

 Figure 3 shows in perspective the blower 20 of Figure 1. An acoustic absorption structure 30 is mounted so

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amovible sur la paroi externe du pulseur 20, en particulier à l'endroit d'un bec de volute 28. Cette structure insonorisante convexe 30 se présente sous'la forme d'une mousse conformée selon la forme du bec 28 pour être installée et retirée facilement.

removable on the external wall of the blower 20, in particular at the location of a volute nozzle 28. This convex sound-absorbing structure 30 is in the form of a foam shaped according to the shape of the nozzle 28 to be installed and removed easily.

 In FIG. 4, it is a volute 29 of the blower 20 which comprises two half-housings 29a and 29b connected to each other and between which is interposed removably an acoustic absorption structure 30 in the form of 'A foam held in place when the half-housings 29a and 29b are closed.

acoustique 30 se présentant sous la forme d'une mousse portée par un cadre 32. La structure d'absorption peut être à cellules ouverts, cellules fermées ou en sachet pour neutraliser également les problèmes d'humidité, d'odeur, etc
Le cadre 32 est conformé à la manière d'un tiroir ajouré formant une grille rigide réalisée, dans cet exemple, en polypropylène moulé. Ce cadre est muni d'un ergot 34 monté sur une charnière film pour faciliter son montage sur la conduite, ainsi que son démontage. L'ergot vient se fixer de manière amovible sur un crochet 35. In Figure 5, a portion of a wall of the pipe 16 is shown. This pipe 16 supports an absorption structure

acoustic 30 in the form of a foam carried by a frame 32. The absorption structure can be with open cells, closed cells or in bags to also neutralize problems of humidity, odor, etc.
The frame 32 is shaped like an openwork drawer forming a rigid grid made, in this example, of molded polypropylene. This frame is provided with a lug 34 mounted on a film hinge to facilitate its mounting on the pipe, as well as its disassembly. The lug is removably attached to a hook 35.

 In all the embodiments presented, the sound absorption structure 30 is arranged in an area of the heating and / or air conditioning apparatus which is particularly sensitive from an acoustic point of view, that is to say an area subject to strong turbulence from the expelled air. Such a structure 30 therefore makes it possible to reduce the noise mainly due to this turbulence, this structure 30 being moreover easy to assemble and disassemble since it is removable.

 It should be understood, however, that these examples are given solely by way of illustration of the subject of the invention of which they do not in any way constitute a limitation.

 Thus, it is possible to install the sound absorption structure in other strategic places of the heating and / or air conditioning apparatus so as to attenuate the annoying noises. It is also possible to shape the foam into complex shapes so as to best adapt it to the element on which it will be mounted.

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 Of course, it is possible to equip the vast majority of the elements of the heating and / or air conditioning device, or only one or two elements constituting it. In the same way, it is possible to equip the same element with several sound-absorbing structures.

 In all cases where this proves useful, the foam can be mounted on a rigid frame so as to facilitate its installation or disassembly.

Claims (11)

 CLAIMS 1. Acoustic absorption structure (30) for heating and / or air conditioning apparatus (1), in particular for a passenger compartment of a motor vehicle, characterized in that said structure (30) is of a shape adapted to be mounted in said device (1) removably in an area subject to strong air turbulence.  2. Structure according to claim 1, characterized in that it is in the form of an elongated foam sleeve of prismatic shape.  3. Structure according to claim 2, characterized in that the foam is surrounded by a perforated rigid frame (32).  4. Structure according to claim 3, characterized in that the frame is a grid of molded plastic material, provided with releasable fixing means (34).  5. A heating and / or air conditioning device (1), in particular for a passenger compartment of a motor vehicle, said device comprising at least: - an external chassis (10) forming a pipe for circulating hot and / or cold air in direction of additional pipes (16,18), - an air propulsion member (20) mounted in the chassis (10), - a means (22; 24) for heating and / or cooling the expelled air mounted in the chassis (10), - at least one flap (26) for deflecting and / or closing off said air flow mounted in the chassis (10), and - a structure (30) for sound absorption according to the any of the preceding claims.  6. Apparatus according to claim 5, characterized in that the sound absorption structure (30) is mounted inside the air propulsion member (20), at the location of a volute (29 ).  7. Apparatus according to claim 6, characterized in that the structure (30) of sound absorption is mounted along at least a wall portion of said volute (29).  8. Apparatus according to claim 5, characterized in that the structure (30) of sound absorption is mounted on the member (20) of air propulsion, in the convex area of volute nozzle (28). <Desc / Clms Page number 7>  9. Apparatus according to claim 5, characterized in that the structure (30) of sound absorption is mounted opposite a flap (26) of a pipe (10; 16; 18) for air circulation.  10. Apparatus according to claim 5, characterized in that the structure (30) of sound absorption is mounted on a flap (26) of a pipe (10; 16; 18) for air circulation.  11. Apparatus according to claim 5, characterized in that the structure (30) of sound absorption is mounted along a wall of a pipe (10; 16; 18) for air circulation.