Hoisting machinery unhooking -prevention device

The utility model relates to a hoisting machinery technical field especially relates to a hoisting machinery unhooking -prevention device. The utility model discloses a hoisting machinery unhooking -prevention device, include: the neck of hook, coupler body, sleeve, linking arm, first pivot, second pivot, fixed arm, anticreep bolt, fastening bolt and spacing dish, neck of hook outside is located to the cover barrel casing, is connected through first pivot rotation between the one end of linking arm and the sleeve, the other end of fixed arm and linking arm passes through the second pivot and rotates and be connected, be provided with the fixed orifices on the coupler body, the fixed arm corresponds the fixed orifices and is provided with the screw hole, and the anticreep bolt passes fixedorifices and screw hole threaded connection, two side arms that the fixed arm set up including the symmetry, two side arms are located the both sides of coupler body, telescopic side arm threaded connection has fastening bolt