PIPING CONNECTION STRUCTURE

摘要

Provided is a piping connection structure which assigns a function to restrict a pipe body from coming off to a member other than a resin tube, improves in sealing performance and can suppress the amount of fuel permeation. A resin tube comprises a tube body portion; a first diameter-expanding portion formed to increase in diameter from an axial end of the tube body portion and axially positioning seal members by holding the seal members in an axial gap with a retainer; and a second diameter-expanding portion formed to further increase in diameter from the first diameter-expanding portion, and to contact an outer circumferential side of the seal members and be connected to the retainer while in contact with the retainer. Thickness of the first diameter-expanding portion is equal to or greater than thickness of the tube body portion.

主权项

1. A piping connection structure comprising:
a pipe body having an annular projection projecting radially outward at some distance from a fore end thereof; a resin tube into which a fore end side of the pipe body is to be inserted; a retainer formed in a hollow cylindrical shape, connected to an axial end of the resin tube, and restricting the pipe body from coming off by being engaged with the annular projection of the pipe body when the pipe body is inserted therein; and a seal member to be disposed in a radial gap between an inner circumferential surface of the resin tube and an outer circumferential surface of the pipe body; the resin tube comprising:
a tube body portion;a first diameter-expanding portion formed to increase in diameter from an axial end of the tube body portion, and axially positioning the seal member by holding the seal member in an axial gap with the retainer; anda second diameter-expanding portion formed to further increase in diameter from the first diameter-expanding portion, and to contact an outer circumferential side of the seal member and be connected to the retainer while in contact with the retainer; and the first diameter-expanding portion having the same or greater thickness than the tube body portion.