Sound Proofing / Insulation: Description and Operation
Low Vibration and Low Noise Body1. General
Effective application of vibration damping and noise suppressant materials reduces engine and road noises. The high-density silencer is used around the engine room and the instrument panel, thus, realizing improvement of the acoustic absorption and sound insulation and reduction in the engine transmission noise, compared with the gasoline engine model.
2. Sound Absorbing and Vibration Damping Materials
^ Foamed urethane sponge and foamed sealing material are applied onto the roof panel and pillars to reduce wind and road noise.
^ A large-size dash inner silencer, dash outer silencer, hood silencer, apron silencers, cowl outer silencer and tunnel inner silencer are used to reduce engine and road noise and improve quietness inside the passenger compartment.
^ The fender liner with the high-density felt is fitted inside the front wheelhouse and the nonwoven felt type fender liner is fitted inside the rear wheelhouse in order to minimize grit, water and road noises.
^ The material having high sound-shielding property is used for the intermediate film of the laminated glass of the window shield glass to reduce wind noise.
^ The silencer on the back side of the instrument panel is highly densified and its applied section is added in order to reduce the engine noise.
^ In place of the asphalt sheet used on conventional models, a vibration damping foam coating is used on the floor of the new model to reduce road noise.
^ The thickness of the vibration damping foam coating has been optimally adjusted for the individual portions. As a result, a lightweight coating has been realized.
3. Reducing Wind Noise
^ A structure that blocks the airflow is used in a portion of the door weather strip (at the front corner) in order to reduce wind noise (A - A cross section).
^ The air turbulence has been eliminated through the use of the hood side seal rubber (B - B cross section).
^ By streamlining the joins between the hood and windshield glass (C - C cross section) and between windshield glass and the roof (D - D cross section), air turbulence has been minimized.
^ Fender seals made of foamed resin are used between the front fender and the side member outer to prevent air from blowing through. (F - F cross section)
^ Parting seals made of flexible resin are employed between the front and rear doors to eliminate air turbulence (F - F cross sections).