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EP-4431708-B1 - AN ACOUSTIC DEVICE FOR A VEHICLE

EP4431708B1EP 4431708 B1EP4431708 B1EP 4431708B1EP-4431708-B1

Inventors

  • PALMIERI, Davide
  • FIGURETTI, Alessio

Dates

Publication Date
20260513
Application Date
20240314

Claims (17)

  1. A sound bypass device (200a; 200b; 200c; 200d) configured to transmit engine-generated sound pulses from an engine (102) of a vehicle (100) to an auditory environment whilst preventing the flow of gases to the auditory environment, the sound bypass device comprising: a sound inlet (202) configured to receive gases exiting or entering the engine of the vehicle; a sound outlet (206) configured to transmit sound pulses to the auditory environment; a chamber (210) connected to the sound inlet at a first end and to the sound outlet at a second end, the chamber being enclosed between the sound inlet and the sound outlet; and a first membrane (212) located within the chamber, the first membrane being configured to transmit engine-generated sound pulses from the gases whilst preventing the movement of gases through the sound bypass device; wherein the sound outlet is defined by a second membrane (214) extending radially from the second end of the chamber, and the second membrane being configured to move in response to sound pulses from the chamber to emit sound pulses from the chamber to the auditory environment, characterised in that the second membrane (214) is extending outwardly away from the chamber 210) from a central point of the sound outlet (206).
  2. The sound bypass device of claim 1, wherein the first membrane comprises bellows (220) or a corrugated spring attached to an internal wall of the chamber.
  3. The sound bypass device of claim 2, wherein the internal wall is an end wall (224) or a side wall (226) of the chamber.
  4. The sound bypass device of any preceding claim, wherein the first membrane is constructed from a sheet of corrugated material and/or wherein the first membrane is composed as a single sheet of material.
  5. The sound bypass device of any preceding claim, wherein the chamber is defined by a first axis (228) that extends between its first end and its second end, and wherein the second membrane extends outwardly of the chamber in (i) a radial direction that extends away from the first axis, and (ii) and an axial direction that is coincident with the first axis and extends away from the chamber.
  6. The sound bypass device of any preceding claim, wherein the second membrane comprises a cross-sectional area that extends perpendicularly to the first axis, the cross-sectional area of the second membrane increasing as it extends away from the chamber.
  7. The sound bypass device of any preceding claim, wherein the second end of the chamber comprises an orifice, the orifice having a first cross-sectional area, and wherein the second membrane has a cross-sectional area at its furthest point from the chamber that is greater than the cross-sectional area of the orifice.
  8. The sound bypass device of any preceding claim, wherein the second membrane is conical in shape.
  9. The sound bypass device of any preceding claim, wherein the chamber further comprises: a first volume (230) located between the sound inlet and the first membrane; and a second volume (232) located between the sound outlet and the first membrane; wherein the first membrane is configured to prevent the movement of gasses between the first volume from the second volume.
  10. The sound bypass device of claim 9, wherein the first volume has a first end located at the first end of the chamber and a second end that is proximal to the second volume, and wherein the first volume has a cross-sectional area that is greater at the second end than it is at the first end, and optionally wherein the rate of increase of the cross-sectional area of the first volume is constant along the length of the first volume, and the second volume has a cross-sectional area that is consistent along the length of the second volume.
  11. The sound bypass device of any claim 8, further comprising a connecting means (234a, 234b) for transferring engine-generated sound pulses waves between the first membrane and the second membrane.
  12. The sound bypass device of claim 11, wherein the connecting means is a rod (243a) or a volume of air (234b) comprised within the second volume.
  13. The sound bypass device of any preceding claim, further comprising a protective cap (236) located at a centre point of the second membrane, the protective cap being configured to isolate the chamber from the auditory environment, and optionally wherein the protective cap is coupled to the second membrane by an insulating seal.
  14. The sound bypass device of any preceding claim, further comprising: a frame (240) for supporting the second membrane as it extends radially from the chamber; and a suspension mechanism (242) coupling the second membrane to the frame.
  15. A vehicle (100) comprising the sound bypass device (200a; 200b; 200c; 200d) of any preceding claim.
  16. The vehicle of claim 15, the vehicle further comprising an exhaust system and a catalytic converter, wherein the sound inlet is connected to a first location on the exhaust system of the vehicle that is located before a catalytic converter of the vehicle.
  17. The vehicle of claim 15 or claim 16, the vehicle further comprising a cabin and, wherein the auditory environment is the cabin of the vehicle, and optionally wherein the vehicle further comprises a dashboard, wherein the sound outlet is located on the dashboard of the vehicle.

Description

This invention relates to an acoustic device for transmitting engine-generated sound pulses from the engine of a vehicle. Passive acoustic bypass devices are known to be implemented into modern-day high-performance vehicles, such as sports cars, to improve the acoustic performance of those vehicles. These acoustic devices are configured to transmit sound obtained from gases either entering or existing the engine of the vehicle into an environment that is either external (i.e., outside) or internal (i.e., inside) to the vehicle. The devices typically comprise a hollow chamber configured to receive input gases and a movable diaphragm that bisects the chamber. The diaphragm is configured to transmit sound pulses through the chamber whilst also preventing the transfer of input gases through the chamber. Existing passive acoustic bypass devices are limited by the levels of static pressure and temperatures that they are able to tolerate. Thus, the input gases for such devices must be obtained from either (i) an input to a vehicle engine, where they have not yet been subjected to combustion processes within the engine itself, or (ii) from a location along the exhaust system of the vehicle that is located between the exhaust outlet and at least one gas treatment component of the exhaust system. These types of input gases are unable to transfer sound pulses that are fully representative of the noise generated during engine combustion processes, as in scenario (i) these gases have not yet been subjected to such processes, and in scenario (ii) the gases have been filtered out by a gas treatment component, diminishing the quality of the sound vibrations that they carry. EP 4130445 describes a sound bypass device configured to transmit engine-generated sound pulses from an engine to a sound outlet whilst preventing flow of gases to the sound outlet. US 2002/157897 describes a device for noise configuration in a motor vehicle having a hollow body which is divided into at least two spaces. One space is connected to a gas-carrying part of an internal combustion engine arranged in the motor vehicle, and the other space is coupled acoustically to an interior and an engine space of the motor vehicle or to the space surrounding the motor vehicle. A vibrational element, which extends into both spaces, is arranged within the hollow body. According to a first aspect there is provided a sound bypass device configured to transmit engine-generated sound pulses from an engine of a vehicle to an auditory environment whilst preventing the flow of gases to the auditory environment, the sound bypass device comprising: a sound inlet configured to receive gases exiting or entering the engine of the vehicle; a sound outlet configured to transmit sound pulses to the auditory environment; a chamber connected to the sound inlet at a first end and to the sound outlet at a second end, the chamber being enclosed between the sound inlet and the sound outlet; and a first membrane located within the chamber, the first membrane being configured to transmit engine-generated sound pulses from the gases whilst preventing the movement of gases through the sound bypass device; wherein the sound outlet is defined by a second membrane extending radially from the second end of the chamber, the second membrane being configured to emit sound pulses from the chamber to the auditory environment. According to a second aspect there is provided a sound bypass device configured to transmit engine-generated sound pulses from an engine of a vehicle to an auditory environment whilst preventing the flow of gases to the auditory environment, the sound bypass device comprising: a sound inlet configured to receive gases exiting or entering the engine of the vehicle; a sound outlet configured to transmit sound pulses to the auditory environment; a chamber connected to the sound inlet at a first end and to the sound outlet at a second end, the chamber being enclosed between the sound inlet and the sound outlet; and a first membrane located within the chamber, the first membrane being configured to transmit engine-generated sound pulses from the gases whilst preventing the movement of gases through the sound bypass device; wherein the sound outlet is defined by a second membrane extending radially from the second end of the chamber, the second membrane extending outwardly from a central point of the sound outlet, and the second membrane being configured to move in response to sound pulses from the chamber to emit sound pulses from the chamber to the auditory environment. The first membrane may comprise bellows attached to an internal wall of the chamber. The first membrane may comprise a corrugated spring attached to an internal wall of the chamber. The internal wall may be an end wall of the chamber. The internal wall may be a side wall of the chamber. The first membrane may be constructed from a sheet of corrugated material. The first membrane may be composed as a single sh