| 摘要 |
PROBLEM TO BE SOLVED: To reduce intake noise in a wide frequency band by utilizing sound waves generated on either one of vibration plates and sound waves generated on the other of them. SOLUTION: This noise controller is provided with the vibration plates 11 for partitioning a silencer 15 into a main sound pressure generating chamber 13 and a back cavity 14 to suppress intake noise by the "synthetic waves" synthesized by main sound waves given into an intake pipe 2 from the main sound pressure generating chamber 13 and sub-sound waves given into the intake pipe 2 from the back cavity 14 by passing through a back cavity discharge passage 19. Since the sound waves generated in not only the main sound pressure generating chamber 13 but also the back cavity 14 are utilized in this way, quantity of energy to be consumed is suppressed. Since "primary frequency of explosion" and "frequency being multiple of the primary frequency of explosion" appear in the "synthetic wave" in the same way as in intake noise, the intake noise can be reduced in a wide frequency band. COPYRIGHT: (C)2007,JPO&INPIT
|
