| 摘要 |
PROBLEM TO BE SOLVED: To improve an intake noise reducing action by largely ensuring amplitude in an axial direction of an elastic member 14 to intake pulsation.SOLUTION: An intake noise reducing device connected to an intake system of an internal combustion engine has a bellows-shaped elastic member 14 connected to an intake passage through a communication pipe, and obtains an intake sound reducing action with the expanding/contracting deformation of the elastic member 14, in addition to an intake sound reducing action as a Helmholtz type resonance element. A peripheral wall 14c of the elastic member 14 has a crest portion 31 and a trough portion 32 connected by a tapered wall 33, and top portions of those are straight line portions 35 and 36. The straight line portions 35 and 36 are formed in cylindrical shapes, so that displacement in a diametrical direction is suppressed to sound pressure changes, and amplitude in an axial direction can be largely obtained.SELECTED DRAWING: Figure 5 |
