Tube connecting structure

A tube connecting structure for a resin tube and a tubular mating member comprising:

• a resin tube having at least one end portion extending straight;
• an engagement member including a cylindrical base fitted into an outer peripheral surface of the one end portion of said resin tube and first engagement means formed integrally with the cylindrical base and engaged with said tubular mating member;
• a ring-shaped elastic seal member directly contacting with and attached onto the outer peripheral surface or inner peripheral surface on an axial intermediate portion of the one end portion of said resin tube;
• a cylindrical press-fitted means having at least one cylindrical body, said body press-fitted into the inner peripheral surface of the one end portion of said resin tube and fixing said engagement member to an outer peripheral surface on the other side of the one end portion of said resin tube, said body including a retaining means for preventing disassembly of said elastic seal member from said resin tube, said retaining means including a radially extending circular surface opposed to said elastic seal member, said circular surface extending outwardly beyond the outer peripheral surface or extending inwardly beyond the inner peripheral surface of the one end portion of said resin tube;
• and
• a tubular mating member having an insertion end portion, which can be relatively inserted into the outer peripheral surface of one end portion of the base of said engagement member by fluid tight-engaging an inner peripheral surface of said tubular mating member with the outer peripheral portion of said ring-shaped elastic seal member attached to the outer peripheral surface of the one end portion of said resin tube;
• or an insertion end portion, which can be relatively inserted into the inner peripheral surface of said press-fitted means by fluid tight-engaging an outer peripheral surface of said tubular mating member with the inner peripheral portion of said seal member attached to the inner peripheral surface of the one end of said resin tube;
• and second engagement means provided on the outer peripheral surface of one of the insertion end portions of said mating member so as to be extended outward radially, said second engagement means being engaged with the first engagement means when one of the insertion end portions is relatively inserted into the one end portion of said resin tube, wherein
• when the insertion end portion of said tubular mating member is inserted into the outer peripheral surface or the inner peripheral surface of the end portion of said resin tube, the second engagement means of said tubular mating member is engaged with the first engagement means of said resin tube, said seal member directly contacting with and interposed between said tubular mating member and said resin tube, thereby sealing the insertion end portion of said tubular mating member and the end portion of said resin tube.

A tube connecting structure for a resin tube and a tubular mating member comprising:

• a resin tube having at least one end portion extending straight;
• an engagement member including a cylindrical base fitted into an outer peripheral surface of the one end portion of said resin tube and first engagement means formed integrally with the cylindrical base and engaged with said tubular mating member;
• a cylindrical press-fitted means having a cylindrical body, said body press-fitted into an inner peripheral surface of the end portion of said resin tube, expanding a diameter of the end portion and fixing said engagement member to the outer peripheral surface of the other end side of the one end portion of said resin tube;
• a ring-shaped extended portion extending from an outer peripheral surface on one end of the body outward radially to exceed an outer peripheral surface on one end of the expanded diameter end portion;
• a ring-shaped elastic seal member attached to and held on the outer periphery of the one end portion of said resin tube corresponding to a space between an one end portion of the base of said engagement member and the ring-shaped extended portion of said cylindrical press-fitted means;
• and
• a tubular mating member having an insertion end portion, an inner peripheral surf ace of the insertion end portion capable of being relatively inserted into the outer peripheral surface of the one end portion of the base of said engagement member by fluidtight-engaging said tubular mating member with an outer peripheral surface of said attached and held ring-shaped elastic seal member;
• protruded second engagement means provided on an outer peripheral surface of the insertion end portion, said second engagement means capable of being engaged with the first engagement means when the insertion end portion is relatively inserted into the one end portion of said resin tube, wherein
• when the insertion end portion of said tubular mating member is inserted into the outer peripheral surf ace on the end portion of said resin tube, the second engagement means of said tubular mating member is engaged with the first engagement means of said resin tube, said seal member directly contacting and interposed between said tubular mating member and said resin tube, thereby sealing the insertion end portion of said tubular mating member and the end portion of said resin tube.