PROBLEM TO BE SOLVED: To fix a light source at a position capable of irradiating the proper amount of light to an object to be irradiated, even if the diameter of a protective pipe is uneven.SOLUTION: An ultraviolet irradiation unit comprises: a light source 2 that emits light including ultraviolet rays a cylindrical protective pipe 3 that surrounds the light source 2 and is configured to allow transmission of the ultraviolet rays from the light source 2 to the outside a holding member 4 that is arranged in the protective pipe 3 with the light source 2 being mounted and has a pair of abutting parts 42, 42 abutting against an inner peripheral surface of the protective pipe 3 at two circumferential points and an elastic member 41 that is arranged between the holding member 4 and the inner peripheral surface of the protective pipe 3 and presses the pair of abutting parts 42, 42 against the inner peripheral surface of the protective pipe 3.SELECTED DRAWING: Figure 2COPYRIGHT: (C)2017,JPO&INPIT【課題】保護管の管径にばらつきがあったとしても、照射対象物に適切な光量を照射できる位置に光源を固定できるようにする。【解決手段】紫外線を含む光を発する光源2と、光源2を包囲した保護管3であって、光源2からの紫外線を外部に透過可能に構成された円筒状の保護管3と、光源2が取り付けられた状態で保護管3内に配置される保持部材4であって、保護管3の内周面に対して周方向の二箇所に当接する一対の当接部42,42を有する保持部材4と、保持部材4と保護管3の内周面との間に配置され、前記一対の当接部42,42を保護管3の内周面に押し付ける弾性部材41とを備える。【選択図】図2
