Solid rocket engine extinguishing and cooling device

The invention, which relates to the technical field of rocket engines, discloses a solid rocket engine extinguishing and cooling device which comprises a rotating mechanism, a feeding mechanism, a spray gun mechanism and a pneumatic control system. An oscillating cylinder Q1 of the rotating mechanism drives a bracket arm to oscillate to adjust the spray gun mechanism to be coaxial with an engine nozzle; a feeding cylinder Q2 of the feeding mechanism drives the spray gun mechanism to feed a cooling medium into a nozzle of the engine nozzle; the cooling medium is sprayed from the spray gun mechanism; the pneumatic control system comprises reversing valves, travel valves and a switch valve, the reversing valve V1 is connected with an oscillating cylinder Q1, and the reversing valve V2 is connected with the feeding cylinder Q2; the travel valve A0 and the travel valve A1 are connected with the oscillating cylinder Q1; the travel valve B0 and the travel valve B1 are connected with the feeding cylinder Q2, the trav