Safe lifting device for conveying wind tunnel test car

The invention relates to a safe lifting device for conveying a wind tunnel test car. The safe lifting device comprises a rectangular upper-frame, bases, two lifting lugs, two pulleys, two guiding rings, and a bidirectional push-pull cylinder, wherein the bases are respectively connected with the two ends of the rectangular upper-frame through vertical columns, the two lifting lugs are arranged at the corners of one end of the rectangular upper-frame, the two pulleys and the two guiding rings are arranged at the corners of the other end of the rectangular upper-frame, the bidirectional push-pull cylinder is arranged at the middle part of the other end of the rectangular upper-frame, one end of each of two steel wire ropes is fixedly connected with the two lifting lugs, and the other end of each of the two steel wire ropes is fixedly connected with a piston rod at two ends of the bidirectional push-pull cylinder after coming around the pulley and the guiding ring, which are arranged on the same side; the bidire