Abstract: An apparatus for connecting two double vacuum pipes for conducting cryogenic fluid consists of a tubular connecting mechanism connected to the outer tube of a double vacuum pipe by a tubular member, a one-touch locking mechanism connected to the outer tube of the other double vacuum pipe by another tubular member inserted in the first-mentioned tubular member, a warming chamber defined between both tubular members, valve mechanisms respectively provided between the tubular members and the inner tubes of the double vacuum pipes which valve mechanisms cooperate to close the inner tubes of the respective double vacuum pipes at the closed position so as to make the inner tube of one of the double vacuum pipes communicate with the warming chamber during the connection of both the double vacuum pipes and to cause the inner tubes of both double vacuum pipes to communicate with each other.

Abstract: A pipe connector for a high-pressure fluid pipe comprises a socket and a plug. The socket includes a housing having a first end portion connected to a high-pressure fluid source, a second end portion receiving a plug, and a bore formed of a valve chamber located on the first end portion side and a plug hole located on the second end portion side, the bore connecting the first and second end portions. The housing includes a valve seat and a valve body disposed in the valve chamber, a sealing ring for sealing the gap between the outer peripheral surface of the valve body and the inner peripheral surface of the plug hole, and a passage adapted to connect the bore portion between the valve seat and the sealing ring to the bore portion on the second end portion side with respect to the sealing ring when the valve body is separated from the valve seat.