PROBLEM TO BE SOLVED: To provide an endoscope for preventing outflow of water in an air supply state by a simple and small-sized structure.SOLUTION: In an endoscope, an air pipeline 210 where air passes through and a water pipeline 240 where water passes through are merged at a merging part 100, and air or water is made to pass through air/water pipeline 270. A shape in a plane where the first center axis 130 in common for the air pipeline 210 and the air/water pipeline 270 and the second center axis 160 of a connection pipeline 152 positioned at the merging part of the water pipeline pass through becomes as follows. For a first tangent 162 at the intersection with the air/water pipeline 270 of the inner wall of the air/water pipeline 270 of the connection pipeline 152, a first angle θ1 formed by a half line on the first center axis 130 coming out to the side of the air pipeline 210 from a first intersection 164 which is the intersection of the first center axis 130 and the first tangent 162 and a half line on the first tangent 162 coming out to the side of the connection pipeline 152 from the first intersection 164 is an obtuse angle.COPYRIGHT: (C)2014,JPO&INPIT【課題】単純で小型な構造で送気状態における水の流出を防止する内視鏡を提供する。【解決手段】内視鏡において、空気が通過する送気管路210と水が通過する送水管路240とは、合流部100において合流し、送気送水管路270には、空気又は水が通される。送気管路210と送気送水管路270の共通の第1の中心軸130と、送水管路の合流部に位置する接続管路152の第2の中心軸160とが通る平面における形状は、次のようになる。接続管路152の送気送水管路270の内壁の送気送水管路270との交点における第1の接線162について、第1の中心軸130と前記第1の接線162との交点である第1の交点164から送気管路210側に出る第1の中心軸130上の半直線と、第1の交点164から接続管路152側に出る第1の接線162上の半直線とがなす第1の角度θ1は、鈍角である。【選択図】図4
