PROBLEM TO BE SOLVED: To provide a smoke ventilation device capable of automatically adjusting a feeding amount of air according to a distance between a tip end of an endoscope and an affected part, and preventing oscillation of the affected part.SOLUTION: A smoke ventilation device comprises: an air feeding tube 9 capable of feeding carbon dioxide gas to the vicinity of a tip end of an endoscope 10； a motor 22 for adjusting an air amount which is fed from the air feeding tube 9； an infrared sensor 15 for measuring a distance between the tip part of the endoscope 10 and an affected part 16； a conversion table 243 in which the air amount which can be fed from the air feeding tube 9 according to the distance, is defined； and a rotation number control part 242 for calculating the air amount of air to be fed, by collating a measurement result of the infrared sensor 15 and the conversion table 243, then controlling an adjustment amount of a motor 22.SELECTED DRAWING: Figure 2【課題】内視鏡先端と患部との距離に応じて気体の送気流量を自動的に調整し、患部の揺れを防止することができる排煙装置を提供する。【解決手段】排煙装置は、内視鏡１０先端近傍に炭酸ガスを送気可能な送気チューブ９と、送気チューブ９から送出される気体量を調節するモータ２２と、内視鏡１０の先端部と患部１６との距離を測定する赤外線センサ１５と、距離に対応して送気チューブ９から送出可能な気体量が定義された変換テーブル２４３と、赤外線センサ１５の測定結果と変換テーブル２４３とを突合して送出する気体量を算出し、モータ２２の調節量を制御する回転数制御部２４２と、を有する。【選択図】図２
