Tube connecting structure

摘要

A tube connecting structure for connecting a resin tube and a tubular mating member. The structure includes an engagement member having a cylindrical base that is attached onto the outer peripheral surface of an end portion of the resin tube and is fixed to the resin tube by a cylindrical press-fitted member. The cylindrical press-fitted member is press-fitted into the inner peripheral surface of the end portion, thereby expanding the diameter of the end portion of the resin tube and fixing the cylindrical base to the resin tube. The engagement member has a plurality of arm portions radially extending from the cylindrical base. First engagement portions, in the form of ratchets, are provided to protrude from tip end portions of the arm portions, such that the first engagement portions can be snap-engaged with a second engagement portion on the tubular mating member. The tubular mating member and the resin tube are directly connected to each other with a ring-shaped elastic seal member positioned therebetween.