Air-to-fuel ratio sensor

摘要

An air-to-fuel ratio sensor of a construction, wherein an oxygen concentration cell having a chamber, at least one side of which is communicative with the atmosphere and an oxygen pump are disposed in mutual confrontation through a clearance chamber, or a spatial chamber having a tiny hole for dispersion, and gas to be measured is introduced into this clearance chamber or the spatial chamber to measure its air-to-fuel ratio from an output of the oxygen concentration cell or a control quantity of the oxygen pump, thereby making it possible to control the internal combustion engine over a wide range other than its theoretical air-to-fuel ratio.