Patent ID: 11869473
Assignee: YAMAHA CORPORATION
Field: Transport (Mechanical engineering)
Classification: CPC G  B | IPC B  G

Claim 0:
1. A hollow structure comprising:
a hollow body with an annular first space; and
at least one resonator in which there is formed an elongated second space with a pair of openings at two ends thereof, each of the pair of openings comprising an opening that opens inwardly toward an interior of the first space, wherein:
a ratio of a length of a centerline of the second space to a length of a centerline of the first space is within a range of from 0.45 to 0.55, and
the second space is disposed in a curve along a circumferential surface of the first space and is shaped such that one of the two ends of the second space is folded back toward the other end.