Safety blow-off valve of gas pressure regulator

The utility model discloses a safety blow-off valve of a gas pressure regulator, which comprises a valve body, two ends of which are respectively provided with a gas inlet and a gas outlet; the column body is fixedly arranged on the valve body and is provided with a first exhaust port which is kept normally open and a second exhaust port in which a first valve plate is rotationally arranged; the plug block is movably arranged in the column body and is blocked at the joint of the valve body and the column body under the action of a pressure assembly arranged in the column body; the side wall of the trigger block is connected with the first valve plate through a spiral driving assembly. Through the arrangement of the first exhaust port and the second exhaust port, when the air pressure in the valve body is high, the plug block is jacked up, so that the first exhaust port is directly communicated with the interior of the valve body, and the pressure relief protection effect is achieved; and when fire blast occur