Mechanically-valved spark plug probe measuring fuel concentration of mixture in engine cylinder, includes resistors sensing pressure, velocity and temperature

摘要

A sensitive section (51C) of the third resistor (50C) is located in the mixture passage. It is connected to a supply (55C) controlled to maintain the resistance value constant. The sensitive sections (51A-C) of the three resistors are located in a fluid passage, such that pressure, velocity and temperature of the fluid are sensibly uniform at this location. An independent claim is included for the corresponding method of measuring the fuel concentration in the mixture.