CONNECTION ELEMENT Russian patent published in 2013 - IPC E21B17/02 

FIELD: construction.

SUBSTANCE: device comprises a connection element made as capable of usage with a complementing connection element, which may be inserted into the specified connection element. The latter comprises a fixing facility, a releasing facility, functioning between permitting and non-permitting positions, at which the fixing facility may or may not move between working and non-working positions, the facility of retention of the releasing facility in the permitting position, and the facility to move the releasing facility between the permitting and preventing positions. The retention facility is engaged with the releasing facility for its fixation in the permitting position. The retention facility may be disengaged from the releasing facility with the help of a complementing connection element.

EFFECT: increased efficiency and reliability of engagement, disengagement, expanded possibilities of usage.

21 cl, 7 dwg