Patent ID: 8096170

Claim:
An apparatus for measuring the cylinder internal pressure of internal combustion engines and, in particular, of gas engines, said apparatus having a first valve ( 5 ) which opens into the cylinder interior space, a measurement chamber ( 6 ) which can be connected to the cylinder interior space and can be disconnected from the latter by means of the first valve ( 5 ), and a pressure sensor ( 8 ) which is arranged in the region of the measurement chamber ( 6 ) in order to measure the pressure in the cylinder interior space ( 1 a ) when the first valve ( 5 ) is open, with at least one second valve ( 13 ) being provided in the region of the measurement chamber ( 6 ), said second valve being able to be changed to a closed position at least when the first valve ( 5 ) is open in order to seal off the measurement chamber ( 6 ) towards the outside, wherein the first valve ( 5 ) comprises a movable valve body ( 4 ) in which the pressure sensor ( 8 ) is arranged.