Backpack type foam fire extinguishing device

The invention discloses a backpack type foam fire extinguishing device. The device comprises a back barrel, a spray gun, a gas storage mechanism, a three-way pipe fitting and a driving pump; the gas storage mechanism is provided with a first outlet and a second outlet, and the first outlet is used for communicating with breathing equipment of a user; the three-way pipe fitting is provided with a first inlet, a third outlet and a fourth outlet, and the first inlet is communicated with the second outlet; and the active pump is provided with an air supply port, a liquid inlet and a liquid outlet, the air supply port is communicated with the fourth outlet, the liquid inlet is communicated with the back barrel, the liquid outlet and the third outlet are communicated with the spray gun at the same time, and the active pump pumps the fire extinguishing foam input from the liquid inlet to the liquid outlet to be output through air pressure generated by air input from the air supply port. The high-pressure air in the