Measuring combustion pressure in combustion chamber of internal combustion engine by detecting changing in length of cylinder head screw or bulging of cylinder head

摘要

The method involves generating a measurement signal for output to an evaluation circuit, based on the elastic deformation of at least one cylinder head screw (6) and/or the cylinder head (4) and/or the cylinder housing (2), caused by the combustion pressure. The measuring signal may be based on a change in length of the cylinder head screw, a bulging of the cylinder head, or a bulging or length change in the cylinder housing. The measurement may use piezoelectric, capacitive, magnetostrictive or electromagnetic force sensors. An Independent claim is included for an apparatus for measuring the combustion pressure.