Abstract: A fluid coupler is provided in which a male coupler is brought into a fixed connection condition in which the male coupler is fixedly connected to a female coupler member and retained at a fixed connection position relative to the female coupler member, the fixed connection condition being cancelled or broken when an excessive tension is applied to a fluid line in which the fluid coupler member is installed such that the tension acts on the male and female coupler members to separate them. A first valve is provided between and slidably engaged with the exterior surface of the male coupler member and the interior surface of the female coupler member. The first valve has a through hole having an outer end opening at the outer surface thereof and an inner end opening at the inner surface thereof to fluidly communicate the fluid passages of the male and female coupler members.

Abstract: Two flanged cylinders, one of which slides inside the other, are kept selectively in firm contact with each other by the engagement of elastic elements and their terminal booths with grips. The elastic elements and grips are fixed, respectively, on the outer perimeter of the inner cylinder and the outer perimeter of the outer cylinder. Engagement is maintained until the traction force applied to the two cylinders exceeds a predetermined value.

Abstract: An improved self-sealing-type double tube joint which has a pair of tubular outer shell 11, 21, each of which having a tubular inner barrier wall 12, 22 fixed therein so as to form a double flow passage. The tubular barrier wall 22 in a male outer shell 21 is closed at front end 23 therof, and a side passage 24 connecting to the flow passage 1 is formed in a side wall of the tubular barrier wall. A male-side ring-like movable valve element 41 is slidably mounted on the tubular inner barrier wall 22 so that the valve element 41 shuts the side passage and faces against an end surface of a tubular barrier wall 12 of the female outer shell 11. A female-side ring-like movable valve element 51 is mounted on the inner tubular barrier wall 12 in the female outer shell 11 so as to face against an end surface of the male tubular outer shell 21.