Patent ID: 7444231

Claim:
A method of mounting an accelerometer to an internal combustion engine, the method comprising the steps of: (a) securing the accelerometer to a mating surface on an engine component, the mating surface being external to a combustion chamber of the engine and located where the accelerometer can generate a signal output that is characteristic of engine knock when it occurs and at least one other combustion behavior inside the combustion chamber during at least a portion of a compression stroke or a combustion stroke associated with the combustion chamber; (b) connecting a signal wire at one end to the accelerometer and at an opposite end to a signal processor; and (c) increasing the signal output's signal-to-noise ratio by taking at least one of the following steps: adapting the mating surface on the engine component to have a surface flatness of no more that 0.002 inches (0.05 millimeters) Total Indicator Reading; adapting the mating surface on the engine component to have a surface roughness Rz of no more than 16 micro-inches (0.40 micrometers); anchoring the signal wire to stationary components of the engine, to reduce signal noise that might otherwise be generated by movement of the signal wire; shielding the signal wire using a conductive sheath or integrated shielding to reduce signal noise; and applying a viscous liquid between the accelerometer and the mating surface before securing the accelerometer and filling voids therebetween with the viscous liquid, thereby increasing stiffness of the connection when the accelerometer is secured to the mating surface.