Backpack type premixed compressed air foam fire extinguishing device

The utility model provides a backpack type premixed compressed air foam fire extinguishing device. The backpack type premixed compressed air foam fire extinguishing device comprises a back frame, a foam box, a first steel cylinder, a second steel cylinder, a steel cylinder fixing support, a first high-pressure cylinder valve, a second high-pressure cylinder valve, a first wheel, a second wheel, a pull rod, a box cover, a switch valve, a steel cylinder fixing bandage, a first pressure reducer A, a second pressure reducer A and a fire extinguishing assembly. The pull rod is provided with a handle B. The handle B is used in cooperation with the first wheel and the second wheel. The whole device can be pushed and pulled, the intensity of firefighters in the rescuing and fire extinguishing process is relieved, after the pressure of gas filled in the first steel cylinder is adjusted to a proper value through the first high-pressure cylinder valve and the first pressure reducer A, the gas is connected to the breathi