PURPOSE: To further shorten the part for a coupling so as to obtain a low-priced tube fitting by providing a first tubular member with a large diameter hole part, a second tubular member provided with a shank comprising an axial hole, a tightening means for tightening a hose, a spring body for supporting a valve body and a valve switching means.
CONSTITUTION: A tube fitting 51 is provided with the coupling main body 2 of a first tubular member comprising a small diameter hole part 22a and a large diameter hole part 22b, and the core member 24 of a second tubular member comprising a mealing member and an axial hole 24b forming a flow passage 52. Between the large diameter hole part 22b and a shank 24c, there are also provided with a tightening means 25 for tightening a hose 31 inserted into the shank 24c, a coil spring 56, a spring body, for supporting the axial hole 24b and a valve body 55, and a valve switching means 53. When the fluid force becomes larger than the force of the coil spring 56 for separating the valve body 55 from an opening, the valve body 55 is pressed to the opening to cut off the flow passage. The valve body 55 can be thus made a rectangular coupling capable of cutting off the flow passage.
YOKOMATSU TAKAHIRO
MITSUNE KENJI
KATO SHINICHIRO
