Abstract: Systems, methods, and devices related to mixing foam fire suppressant are provided. A foam proportional mixing device includes a first pump. The first pump includes an inlet pipe coupled with a first housing, such that the inlet pipe is in fluid communication with a first cavity defined by the first housing. The first pump includes a foam receiving port arranged on the inlet pipe and a pair of rotors positioned within the first housing. The foam proportional mixing device includes a second pump. The second pump includes a pair of gears located within a second cavity defined by a second housing. The foam receiving port is in communication with an outlet of the second pump, such that the first pump is in fluid communication with the first cavity.

Abstract: A foam proportional mixing device includes a Roots pump and a gear pump. The Roots pump comprises a Roots pump inlet, a pair of rotors and a fluid guide member. The fluid guide member is arranged in the Roots pump inlet, and is configured to guide fluid to flow to the pair of rotors and provide driving forces to the pair of rotors for rotating same in opposite directions from each other. The gear pump includes a pair of gears. The foam proportional mixing device includes a rotor shaft of one rotor in the pair of rotors of the Roots pump is connected to a gear shaft of one gear in the pair of gears of the gear pump, such that the one rotor drives the one gear to rotate.

Abstract: A foam proportional mixing device, comprising a Roots pump and a gear pump. The Roots pump comprises a Roots pump inlet, a pair of rotors and a fluid guide member. The fluid guide member is arranged in the Roots pump inlet, and is configured to guide fluid to flow to the pair of rotors and provide driving forces to the pair of rotors for rotating same in opposite directions from each other. The gear pump comprises a pair of gears. The foam proportional mixing device is configured as follows: a rotor shaft of one rotor in the pair of rotors of the Roots pump is connected to a gear shaft of one gear in the pair of gears of the gear pump, so as to drive the one gear by means of the one rotor to rotate. The foam proportional mixing device can achieve the function of the proportional mixing of foam and water by means of a simple and compact structure, moreover, the device is convenient to use, and can comply with fire-fighting work on various occasions.