Acoustic resonance device

Abstract

An acoustic resonance device is installed in a compartment of a vehicle so as to reduce a low-frequency sound pressure (or noise) dependent upon a natural vibration. Specifically, an acoustic resonance device is a panel/diaphragm resonator, a resonance pipe, or a Helmholtz resonator, the inner space of which communicates with the compartment via an opening. The acoustic resonance device is positioned in proximity to an antinode of sound pressure owing to a natural vibration occurring in a driver/passenger space inside the compartment. Alternatively, the acoustic resonance device increases a particle velocity at a specific natural frequency or decreases sound pressure at an excitation frequency which occurs due to an external condition of the vehicle. The acoustic resonance device can be installed in a roof, a seat, a pillar supporting the roof, or a door of a vehicle.

1 . An acoustic resonance device comprising at least one resonator which has an inner space and an opening, wherein the inner space of the resonator communicates with a compartment of a vehicle via the opening, and wherein the resonator reduces sound pressure at a specific natural frequency corresponding to an antinode of a natural vibration emerging in a driver/passenger space inside the compartment of the vehicle. 
     
     
         2 . The acoustic resonance device according to  claim 1 , wherein the resonator is positioned to reduce sound pressure at the specific natural frequency corresponding to the antinode of the natural vibration whose position is closest to the driver/passenger space among a plurality of antinodes of the natural frequency occurring in the compartment of the vehicle. 
     
     
         3 . An acoustic resonance device comprising at least one resonator which has an inner space and an opening, wherein the inner space of the resonator communicates with a compartment of a vehicle via the opening, and wherein the resonator increases a particle velocity at a specific natural frequency corresponding to an antinode of a natural vibration emerging in a driver/passenger space inside the compartment of the vehicle. 
     
     
         4 . The acoustic resonance device according to  claim 1 , wherein the resonator reduces sound pressure at an excitation frequency, which occurs due to an external condition of the vehicle and which differs from the specific natural frequency, by way of resonance. 
     
     
         5 . The acoustic resonance device according to  claim 3 , wherein the resonator reduces sound pressure at an excitation frequency which occurs due to an external condition of the vehicle and which differs from the specific natural frequency. 
     
     
         6 . The acoustic resonance device according to  claim 4 , wherein the natural vibration is a primary mode of vibration spreading sound pressure in a width direction of the vehicle. 
     
     
         7 . The acoustic resonance device according to  claim 5 , wherein the natural vibration is a primary mode of vibration spreading sound pressure in a width direction of the vehicle. 
     
     
         8 . The acoustic resonance device according to  claim 4 , wherein the natural vibration is a secondary mode of vibration spreading sound pressure in a forward-backward direction of the vehicle. 
     
     
         9 . The acoustic resonance device according to  claim 5 , wherein the natural vibration is a secondary mode of vibration spreading sound pressure in a forward-backward direction of the vehicle. 
     
     
         10 . The acoustic resonance device according to  claim 4 , wherein at least one seat is facilitated in the driver/passenger space so that the resonator is installed in the seat. 
     
     
         11 . The acoustic resonance device according to  claim 5 , wherein at least one seat is facilitated in the driver/passenger space so that the resonator is installed in the seat. 
     
     
         12 . The acoustic resonance device according to  claim 4 , wherein the resonator is installed in a roof of the vehicle. 
     
     
         13 . The acoustic resonance device according to  claim 5 , wherein the resonator is installed in a roof of the vehicle. 
     
     
         14 . The acoustic resonance device according to  claim 4 , wherein the resonator is installed in a pillar supporting a roof of the vehicle. 
     
     
         15 . The acoustic resonance device according to  claim 5 , wherein the resonator is installed in a pillar supporting a roof of the vehicle. 
     
     
         16 . The acoustic resonance device according to  claim 4 , wherein the resonator is installed in a door of the vehicle. 
     
     
         17 . The acoustic resonance device according to  claim 5 , wherein the resonator is installed in a door of the vehicle. 
     
     
         18 . The acoustic resonance device according to  claim 1 , wherein the opening of the resonator is directed towards the outside of the vehicle. 
     
     
         19 . The acoustic resonance device according to  claim 3 , wherein the opening of the resonator is directed towards the outside of the vehicle. 
     
     
         20 . The acoustic resonance device according to  claim 1 , wherein the resonator is attached to a roof of the vehicle and positioned opposite to the internal space of the compartment so as to communicate with an outside air of the vehicle, and wherein the opening of the resonator is directed in proximate to a hole which runs through the roof of the vehicle and which communicates with the internal space of the compartment. 
     
     
         21 . The acoustic resonance device according to  claim 3 , wherein the resonator is attached to a roof of the vehicle and positioned opposite to the internal space of the compartment so as to communicate with an outside air of the vehicle, and wherein the opening of the resonator is directed in proximate to a hole which runs through the roof of the vehicle and which communicates with the internal space of the compartment.