Method and device for detecting a fluid flow rate

摘要

A method and device are provided for detecting a fluid flow rate, said device comprising a body in which is formed a passage for the fluid, said passage comprising at least two cross sections of different values, a piston having two faces cooperating with the housing, said piston defining with said housing two zones situated on each side of the two faces of said piston, means for returning said piston to a first position or rest position, each of said zones being substantially at the same pressure as said passage at the level of one of the two cross sections.