Blind bolt fastening device

A blind bolt fastening device, comprising a screw cap (4) and a screw (8), wherein a mounting hole (7-1) capable of allowing the screw cap (4) to pass through is formed in a plate (7) to be connected;

• top end of the screw cap (4) is connected to a fixed plate (2) in a spot welding manner;
• a plurality of elastic hinges (3) are uniformly mounted on the fixed plate (2);
• one end of each elastic hinge (3) is rotatably fixed on the fixed plate (2);
• connection points between the elastic hinges (3) and the fixed plate (2) do not exceed outer edge of the fixed plate (2);
• the other end of each elastic hinge (3) is connected to a Z-shaped gasket (1) in a spot welding manner;
• in an initial state, the plurality of Z-shaped gaskets (1) are uniformly distributed and fitted onto outer wall of the screw cap (4) along a circumferential direction;
• when needing to pass through the mounting hole (7-1), the plurality of Z-shaped gaskets (1) may be folded through the elastic hinges (3) to top end of the screw cap (4) and form elastic potential energy for rebounding;
• contact surfaces of the Z-shaped gaskets (1) and the screw cap (4) are curved surfaces I (1A) having the same curvature radius as outer surface of the screw cap (4);
• contact surfaces of the Z-shaped gaskets (1) and the mounting hole (7-1) of the plate (7) are curved surfaces II (1B) having the same curvature radius as inner surface of the mounting hole (7-1);
• and the spot welding strength between the elastic hinges (3) and the Z-shaped gaskets (1) ensures that the Z-shaped gaskets (1) are pressed against the plate (7) under the pre-tension action of the bolt after being reset, and after that, the Z-shaped gaskets (1) and the elastic hinges (3) are automatically separated.