| 摘要 |
Provided is a resonator made of synthetic resin provided in an intake path of an engine. An air chamber forming the resonator is formed by melt-welding a circumferential wall portion of a first box forming body and a circumferential wall portion of a second box forming body, while abutting the circumferential wall portions against each other, the first box forming body including a bottom surface portion and the circumferential wall portion surrounding the bottom surface portion, and the second box forming body including a bottom surface portion and the circumferential wall portion surrounding the bottom surface portion. A circumferential groove is formed on an upper end portion of the circumferential wall portion of the first box forming body, and a circumferential protrusion is formed in an upper end portion of the circumferential wall portion of the second box forming body, the circumferential protrusion being melt-welded to a groove bottom of the circumferential groove by being received in the circumferential groove during abutment. An upper end surface between an outer wall surface in the circumferential wall portion of the first box forming body and the circumferential groove is located above the upper end surface between the inner wall surface and the circumferential groove. |
