Closing structure for tube member and engine provided therewith

A closing structure comprising:

• a fluid reservoir for storing a fluid;
• a tube member having a mouth end surface at a tip in an axial direction of the tube member, the tube member having an inside communicating with the fluid reservoir;
• a gasket configured to be disposed on the mouth end surface of the tube member in the axial direction of the tube member;
• an end cap configured to:
• (i) be attached to the tube member;
• and (ii) close the tube member at the mouth end surface of the tube member through the gasket;
• and
• a clamping piece fixed to the end cap,
• wherein:
• the gasket is clamped in an axial direction of the end cap by the end cap and the clamping piece;
• the gasket includes:
• (i) a closing portion configured to be sandwiched between the mouth end surface of the tube member and the end cap in a state where the end cap closes the tube member;
• and (ii) a detachment prevention portion configured to be clamped between the clamping piece and the end cap in the state where the end cap closes the tube member;
• and
• the closing portion and the detachment prevention portion do not overlap with each other when viewed from the axial direction of the end cap.