Combustion process parameter sensor

Abstract

To provide for simultaneous transmission of pressure signals and light signals from the combustion chamber (CC) of an internal combustion engine or, selectively, either one or the other of the pressure or light signals, independently, a spark plug-type housing (1, 2) has a glass plug (3) fitted therein, the end face of which at the side remote from the combustion chamber engaging a piezo-ceramic ring (4). The inner opening of the ring (4) transmits light from the glass plug or rod 3 to a light guide fiber cable (7) which, concentrically and insulated from each other, has a metal woven sleeve (10) placed thereabout, and an outer metallic jacket (12), the woven sleeve (10) being connected to a flanged ring (6, 6a) engaging one end face of the piezo-ceramic ring (4), the other end face being connected to the outer metallic sleeve (12) to provide a coaxial electrical signal output cable, with the inner portion thereof surrounding and forming a jacket for the light guide fiber cable (7).

Dependencies are inferred from the claim text.