PROBLEM TO BE SOLVED: To reduce leakage from a branching portion of a double pipe.SOLUTION: A liquid injection apparatus comprises: a supply pipe for injecting a liquid and a suction flow passage member for sucking the liquid. A portion of the supply pipe forms a double pipe in conjunction with a portion of the suction flow passage member. An inner pipe member, which includes the inner pipe of the double pipe of the supply pipe and the suction flow passage member, comprises: an inner pipe portion forming the double pipe and a branching portion connected to the inner pipe portion and protruding through a hole opening in a wall of an outer pipe member which includes the outer pipe of the double pipe. The outer pipe member comprises a retaining portion made from an elastic member which protrudes from the periphery of the hole to the outside of the outer pipe member and seals the outer peripheral surface of the branching portion.SELECTED DRAWING: Figure 7COPYRIGHT: (C)2017,JPO&INPIT【課題】二重管の分岐部における漏れの低減。【解決手段】液体を噴射するための供給管と、液体を吸引するための吸引流路部材と、を備え、前記供給管の一部は、前記吸引流路部材の一部と二重管を形成し、前記供給管と前記吸引流路部材とのうち前記二重管の内管を含む方である内管部材は、前記二重管を形成する内管部と、前記内管部に接続され、前記二重管の外管を含む方である外管部材の壁に開いた孔から突き出た分岐部と、を備え、前記外管部材は、前記孔の周囲から前記外管部材の外に向かって突き出て、前記分岐部の外周面をシールするための弾性部材である保持部を備える液体噴射装置。【選択図】図7
