DUCT DEVICE

• Main Authors: MAEDA KOJI, SAWADA YUICHIRO, OHIRA EIJI
• Format: Patent
• Language: English; Japanese
• Published: 13.05.2024
• Subjects: BLASTING; ENGINE PLANTS IN GENERAL; ENGINEERING ELEMENTS AND UNITS; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNALCOMBUSTION ENGINES; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES ORENGINES IN GENERAL; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVEFUNCTIONING OF MACHINES OR INSTALLATIONS; HEATING; JOINTS OR FITTINGS FOR PIPES; LIGHTING; MACHINES OR ENGINES IN GENERAL; MEANS FOR THERMAL INSULATION IN GENERAL; MECHANICAL ENGINEERING; PIPES; STEAM ENGINES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; THERMAL INSULATION IN GENERAL; WEAPONS

To provide a duct device capable of sufficiently muffling noise while suppressing deterioration of performance.SOLUTION: A duct device includes a fan blowing exhaust gas by rotating around an axis, and an exhaust duct provided on a downstream side of the exhaust gas in the fan and extending along an axial direction. The exhaust duct has a plurality of acoustic parts arranged in a circumferential direction so as to surround the axis. The acoustic part includes a first acoustic tube having a first inlet opening facing the upstream side and a first outlet opening facing the downstream side, and a second acoustic tube having a second inlet opening facing the upstream side and arranged at the same position in the axial direction as the first inlet opening and a second outlet opening facing the downstream side and arranged adjacently to the same position in the axial direction as the first outlet opening. A tube length of the first acoustic tube and a tube length of the second acoustic tube are different from each other so that sound pressures from the first outlet opening and the second outlet opening cancel with each other.SELECTED DRAWING: Figure 1 【課題】性能劣化を抑制しつつ、十分に消音することができるダクト装置を提供する。【解決手段】ダクト装置は、軸線回りに回転することで排気ガスを送風するファンと、ファンにおける排気ガスの下流側に設けられて軸線方向に延びる排気ダクトと、を備え、排気ダクトは、軸線を囲うように周方向に配列された複数の音響部を有し、音響部は、上流側を向く第一入口開口、及び、下流側を向く第一出口開口を有する第一音響管と、上流側を向き第一入口開口と同一の軸線方向位置の第二入口開口、及び、下流側を向き第一出口開口と同一の軸線方向位置に近接配置される第二出口開口を有する第二音響管と、を有し、第一出口開口と第二出口開口から出る音圧同士が互い打ち消し合うように、第一音響管と第二音響管の管長が互いに異なる長さとされている。【選択図】図１