PROBLEM TO BE SOLVED: To combine suppression of creeping discharge between cathode and anode, and cooling of a radiation generating tube 2, in a radiation generating unit 1 in which the radiation generating tube 2 including a vacuum container having a cathode and an anode at respective ends of an insulating tubular member is placed in a housing container 11 filled with an insulating liquid 4, while being arranged in an insulating outer cylindrical tube 5 by leaving a gap 6 around, together with a drive circuit 3 for controlling the driving of the radiation generating tube 2.SOLUTION: A barrier 7 for partitioning a gap 6 between a radiation generating tube 2 and an outer cylindrical tube 5 is provided while leaving a flow path, for allowing flow of an insulating liquid 4 between the cathode side and anode side of the radiation generating tube 2 without interconnecting the cathode side and anode side linearly, in the gap 6.COPYRIGHT: (C)2014,JPO&INPIT【課題】絶縁性の管状部材の両端にカソードとアノードを有する真空容器を備えた放射線発生管2を、周囲に空隙6をあけて絶縁性の外筒管5の内部に配置した状態で、放射線発生管2の駆動を制御する駆動回路部3と共に、絶縁性液体4で満たされた収納容器11の内部に配置した放射線発生ユニット放射線発生ユニット1において、カソードとアノード間の沿面放電の抑制と放射線発生管2の冷却とを両立させる。【解決手段】放射線発生管2と外筒管5の間の空隙6を仕切る障壁7を、放射線発生管2のカソード側とアノード側との間の絶縁性液体4の流れを許容し、しかもカソード側とアノード側とを直線的に連通させることのない流路を前記空隙6内に残して設ける。【選択図】図1
