초록 ▼

An active foam system for noise and vibration control which employs embedded PVDF layers (12) in a urethane foam pad (13). The system can be used to isolate and/or attenuate vibration. It can also be used to cause a reduction in far-field acoustic pressure and to act as a structurally radiated speak

An active foam system for noise and vibration control which employs embedded PVDF layers (12) in a urethane foam pad (13). The system can be used to isolate and/or attenuate vibration. It can also be used to cause a reduction in far-field acoustic pressure and to act as a structurally radiated speaker (130).

대표청구항 ▼

[ We claim:] [9.] An active speaker system for creating a desired sound, said system comprisinga first layer of foam, a bottom surface of said first layer of foam being substantially planar and a top surface of said first layer being configured in a first wave form,a second layer of foam, a bottom s

[ We claim:] [9.] An active speaker system for creating a desired sound, said system comprisinga first layer of foam, a bottom surface of said first layer of foam being substantially planar and a top surface of said first layer being configured in a first wave form,a second layer of foam, a bottom surface of said second layer of foam being configured in a second wave form which matches the first wave form of said first layer of foam and a top surface of said second layer being substantially planar,an active film means embedded between the top surface of said first layer of foam and the bottom surface of said second layer of foam and having a third wave form which matches said first wave form and said second wave form, said active film means electrically activated to produce vibration, anda supporting means engaging the substantially planar bottom surface of said first layer of foam that restricts in-plane motion of the active film means, whereby said vibration of said active film means causes said active film means to act as a speaker due to the third wave form of the active film means whose shape is kept fixed by said active film means being embedded between said first layer of foam and said second layer of foam leading to out-of-plane motion of said active speaker system with attendant vibration and noise.