Bass sound production device for a motor vehicle.

Abstract

The invention relates to a device (1) for producing low-frequency sounds for a motor vehicle passenger compartment (2), comprising a loudspeaker (4) designed to diffuse sounds and disposed in a primary volume (5) delimited by a first wall (6), the device (1) comprising at least one secondary volume (10), each delimited by a second wall (11), the second wall (11) delimiting at least one opening (12), each closed by a passive radiator (13), the device (1) comprising at least one acoustic duct (16), designed to establish fluidic communication between the primary volume (5) and at least one secondary volume (10) and to form an acoustic path between the loudspeaker (4) and the passive radiator (13), each acoustic duct (16) being connected to the primary (5) and secondary (10) volumes by, respectively, a first (7) and a second (17) inlet formed in the first (6) and second (11) walls, respectively. (Figure 1)

Description

Title of the invention: Device for producing low-frequency sounds for a motor vehicle.

[0001] The technical field relates to vehicle bass sound production devices, center consoles incorporating at least one such bass sound production device, vehicle passenger compartments featuring such a center console and motor vehicles featuring such a passenger compartment.

[0002] Car manufacturers take great care to improve passenger comfort in their vehicles. Indeed, for car manufacturers, the quality of finish and the level of equipment in their vehicles are essential to differentiate themselves from other brands. In this context, the production of ambient sound in a passenger compartment is obviously important.

[0003] Today, audio systems designed to generate low frequencies, i.e., between 20 Hz and 200 Hz, in a car interior generally include a subwoofer. Such a subwoofer consists of a large-diameter speaker, usually larger than 165 mm, combined with a resonating chamber, encompassing the speaker's voice coil, of several liters (sometimes exceeding 10 liters). Due to its significant size, the resonating chamber is generally located in the rear of the vehicle, particularly in the trunk, especially behind a side trim panel, or even in a spare tire well. Occasionally, this resonating chamber may be located under a front seat if the vehicle's design allows.When attempting to reduce the size of the subwoofer and / or speaker to facilitate its integration into the vehicle, certain frequencies, the lowest in the spectrum, are usually lost.

[0004] To overcome the resonance volume, one solution is to directly connect the rear of the loudspeaker to the outside of the vehicle. This is achieved by making a hole that opens directly to the outside, sometimes replaced by an acoustic pathway between the rear of the loudspeaker and the exterior of the vehicle. However, such communication with the outside of the vehicle can lead to problems with sound insulation and / or noise transmission from the outside.

[0005] Thus, integrating a bass speaker with suitable acoustic characteristics into a passenger compartment is particularly complicated by the dimensions required for the loudspeaker and the associated resonance volume. Therefore, there is a need for a solution to facilitate the integration of such a bass speaker.

[0006] The present invention aims to overcome the problems described above. In this technical context, one objective of the present invention is to provide a low-frequency sound production device that is easy to integrate while exhibiting satisfactory acoustic qualities.

[0007] To this end, the present invention relates to a low-frequency sound production device designed to be installed in a motor vehicle cabin, the device comprising a loudspeaker designed to diffuse sounds in the cabin and disposed in a primary volume delimited by a first wall, the device comprising at least one secondary volume each delimited by a second wall, the second wall delimiting at least one opening each closed by a passive radiator, the device comprising at least one acoustic duct, designed to put the primary volume into fluidic communication with at least one secondary volume and to form an acoustic path between the loudspeaker and the passive radiator, each acoustic duct being connected to the primary and secondary volumes by respectively a first and a second inlets provided in the first respectively the second wall.

[0008] The invention also relates to a central console for a motor vehicle passenger compartment comprising at least one low-frequency sound production device according to the invention integrated into the central console.

[0009] The invention further relates to a motor vehicle passenger compartment comprising a central console according to the invention.

[0010] The invention finally relates to a motor vehicle comprising a passenger compartment according to the invention.

[0011] Thus, the bass sound production device according to the invention makes it possible to produce bass sounds over a suitable frequency range while facilitating its integration into the passenger compartment. The device thus allows for a reduction in the size of the loudspeaker without causing any loss of bandwidth. Integration is facilitated since the primary and secondary volumes are located in different positions, while each acoustic duct has a variable geometry adaptable to installation constraints. In addition, the technical characteristics of the passive radiator are easily modified to adapt the characteristics of the device. Experience shows that the acoustic performance of the device according to the invention exhibits a high degree of homogeneity within the passenger compartment. Thus, the device according to the invention makes it possible to obtain a center console integrating the device for diffusing bass sounds with high-quality reproduction.The device thus facilitates its integration into the passenger compartment. Finally, the bass sound production device according to the invention makes it possible to reduce the dimensions of the loudspeaker usually used, which reduces costs.

[0012] According to one embodiment of the device, each acoustic conduit forms a pipe having at least one bend. Thus, the device is particularly adaptable to installation constraints.

[0013] According to one possibility, the device is designed to be integrated at least partially into a central console of the vehicle.

[0014] Advantageously then, each acoustic duct is designed to extend along the longitudinal direction of the center console, bypassing a gear shift control on the center console.

[0015] Depending on one possibility of the passenger compartment, each passive radiator is positioned opposite a footwell and / or a front seat.

[0016] In one embodiment of the passenger compartment, the loudspeaker is oriented to emit sounds towards rear passengers of the passenger compartment.

[0017] According to one possibility of the passenger compartment, the console includes two acoustic ducts arranged on each side of a gearbox control of the console.

[0018] The invention will be better understood upon reading the following detailed description, given solely by way of non-limiting example and made with reference to the accompanying drawings in which:

[0019] [Fig-1] [Fig.1] represents a schematic view of a production device low-pitched sounds according to the invention;

[0020] [Fig.2] [Fig.2] represents a partial perspective view of a device of the [Fig.l] integrated into a central console;

[0021] [Fig.3] [Fig.3] represents a partial longitudinal cross-sectional view of the console central of the [Fig.2];

[0022] [Fig.4] [Fig.4] represents a partial top view of the center console of the [Fig.2],

[0023] In these figures, the same references are used to designate the same elements.

[0024] A low-frequency sound production device 1 according to the invention, illustrated in the figures, is designed to be installed in a motor vehicle passenger compartment 2, shown schematically in [Fig. 1]. The low-frequency sound production device 1 is particularly suitable for integration into a central console 3 of the vehicle, illustrated in Figures 2 and 3.

[0025] The device 1 comprises a loudspeaker 4, shown schematically in [Fig. 1], designed to diffuse sounds in the passenger compartment 2. The loudspeaker 4 has characteristics adapted to the production of low-frequency sounds, in particular those with a frequency between 20 Hz and 200 Hz. The loudspeaker 4 is arranged in a primary volume 5 delimited by a first wall 6. The primary volume 5 has, for example, a volume on the order of a few fractions of a liter to a few liters. The first wall 6 forms a closed volume open exclusively by a first inlet 7 and a bay 8 allowing the communication of a diaphragm 9 of the loudspeaker 4 with the cabin 2. To facilitate understanding of figures 2 and 3, the primary volume 5 is not shown on these figures.

[0026] As schematically shown in [Fig. 1], the device 1 further comprises at least one secondary volume 10, each delimited by a second wall 11. Each second wall 11 delimits at least one opening 12, each closed by a passive radiator 13. Each secondary volume 10 has a volume ranging from a few fractions of a liter to several liters. The opening 12 is, for example, oriented along an axis inclined relative to that of the bay 8.

[0027] To facilitate understanding of the figures, the passive radiator 13 is omitted in figures 2 and 3.

[0028] Each passive radiator 13 refers to a component that acts as a sound emitter without an active power source. The passive radiator 13 is designed to vibrate or resonate in response to the sound vibrations produced by the loudspeaker 4. In the example illustrated in [Fig. 1], the passive radiator 13 comprises a suspended diaphragm 14 held by a suspension 15, exhibiting some damping, closing the opening 12.

[0029] The device 1 also includes at least one acoustic conduit 16, designed to establish fluidic communication between the primary volume 5 and at least one secondary volume 10. Each acoustic conduit 16 is designed to form an acoustic path CA, shown schematically in [Fig. 3], between the loudspeaker 4 and the passive radiator 13. Each acoustic conduit 16 is connected to the primary volume 5 and the secondary volume 10 by, respectively, the first 7 and a second 17 inlets formed in the first 6 and second 11 walls, respectively. Each acoustic conduit 16 is, for example, made using molded plastic elements.

[0030] Each acoustic duct 16 has a reduced cross-section compared to its length and / or the dimensions of the primary 5 and secondary 10 volumes. Thus, each acoustic duct 16 forms a pipe with at least one bend 18, illustrated in [Fig. 3]. In the example shown in Figures 2 and 3, each acoustic duct 16 has a square cross-section at the first inlet 7, transitioning to a rectangular cross-section towards the second inlet 17.

[0031] As illustrated in [Fig. 2], each acoustic duct 16 is designed to extend globally along a longitudinal direction DL, illustrated in [Fig. 2], from the central console 3, bypassing a gearshift control 19 of the central console 3, illustrated in [Fig. 4]. To this end, the primary volume 5 is connected to two acoustic ducts 16 extending around a void 20 designed to accommodate the gearshift control 19.

[0032] As illustrated in Figures 2 and 3, each passive radiator 13 is positioned and oriented opposite a footwell of a front passenger or the driver of the vehicle. Alternatively, each passive radiator 13 is positioned opposite a front seat.

[0033] In the example illustrated in figures 2 and 3, the loudspeaker 4 is oriented to emit sounds towards the rear passengers.

[0034] Alternatively, each acoustic conduit 16 is, at least in part, disposed in a floor of the vehicle.

[0035] Thus, the bass-producing device 1 makes it possible to produce bass sounds over a suitable frequency range while facilitating its integration into the passenger compartment 2. Device 1 therefore allows for a reduction in the size of the loudspeaker 4 without causing any loss of bandwidth. Integration is facilitated since the primary 5 and secondary 10 volumes are located in different positions, while each acoustic duct 16 has a variable geometry adaptable to installation constraints. Furthermore, the technical characteristics of the passive radiator 13 are easily modified to adapt the characteristics of device 1.

[0036] The invention is not limited to the embodiment of the low-frequency sound production device described above, only by way of example, but other embodiments can be designed by a person skilled in the art without departing from the scope and extent of the present invention.

Claims

Demands

1. A low-frequency sound production device (1) designed for installation in a motor vehicle passenger compartment (2), the device (1) comprising a loudspeaker (4) designed to diffuse sounds in the passenger compartment (2) and disposed in a primary volume (5) delimited by a first wall (6), the device (1) comprising at least one secondary volume (10) each delimited by a second wall (11), the second wall (11) delimiting at least one opening (12) each closed by a passive radiator (13), the device (1) comprising at least one acoustic duct (16), designed to connect the primary volume (5) with at least one secondary volume (10) and to form an acoustic path (AC) between the loudspeaker (4) and the passive radiator (13),each acoustic duct (16) being connected to the primary (5) and secondary (10) volumes by respectively a first (7) and a second (17) inlets provided in the first (6) and second (11) wall respectively.

2. Device (1) according to claim 1, characterized in that each acoustic conduit (16) forms a pipe having at least one bend (18).

3. Device (1) according to claim 1 or 2, characterized in that it is designed to be integrated at least in part into a central console (3) of the vehicle.

4. Device (1) according to claim 3, characterized in that each acoustic conduit (16) is designed to extend along the longitudinal direction (DL) of the central console (3) bypassing a gearbox control of the central console (3).

5. Central console (3) for a motor vehicle passenger compartment (2) comprising at least one device (1) for producing bass sounds according to any one of claims 1 to 4 integrated into the central console (3).

6. Motor vehicle passenger compartment (2) comprising a central console (3) according to claim 5.

7. Vehicle passenger compartment (2) according to claim 6, characterized in that each passive radiator (13) is arranged opposite a footwell and / or a front seat.

8. Vehicle passenger compartment (2) according to claim 6 or 7, characterized in that the loudspeaker (4) is oriented to emit sounds towards rear passengers of the passenger compartment (2).

9. Vehicle passenger compartment (2) according to any one of claims 6 to 8, characterized in that the console (3) has two acoustic ducts (16) arranged on each side of a gearbox control of the console (3).

10. Motor vehicle comprising a passenger compartment (2) according to any one of claims 6 to 9.

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