| 摘要 |
A resonator consisting of a synthetic resin is provided in the air intake path of an engine. An air chamber which forms the resonator is formed by welding a first box forming body and a second box forming body together, the first box forming body being provided with a bottom surface section and a peripheral wall section surrounding the bottom surface section, the second box forming body having a bottom surface section and a peripheral wall section surrounding the bottom surface section. The first and second box forming bodies are welded together at the respective peripheral wall sections in such a manner that peripheral wall sections are abutted against each other. A circumferential groove is formed in the upper end of the peripheral wall section of the first box forming body, and a circumferential ridge is formed on the upper end of the peripheral wall section of the second box forming body, the circumferential ridge being, when the first and second box forming bodies are abutted against each other, received in the circumferential groove and welded to the bottom of the circumferential groove. An upper end surface of the peripheral wall section of the first box forming body, the upper end surface being located between the outer wall surface of the peripheral wall section and the circumferential groove, is located above an upper end surface of the peripheral wall section of the first box forming body, the upper wall section being located between the inner wall surface of the peripheral wall section and the circumferential groove. |
