Patent ID: 7475589

Claim:
A knock sensor for attachment to a surface of an internal combustion engine, said sensor comprising: a tubular support member having a top surface and a bottom surface, and having a hole extending therethrough from said top surface to said bottom surface, said bottom surface dimensioned to make contact with the surface of said internal combustion engine; a piezoelectric element held by the support member; a covering member mounted to the support member and covering at least a portion of the top surface of the support member, said covering member having a hole therethrough in registry with the hole in said support member when said cover member is attached to said support member, the covering member including a plurality of holes formed in a portion thereof that covers the top surface of the support member, and the support member including a plurality of projecting portions formed in the top surface thereof, said projection portions being dimensioned to engage and be received in the holes of the covering member; and a fixing member extending though the hole in said cover member and the hole in said support member, said fixing member tightening the knock sensor from the top surface of the support member, while the bottom surface of the support member makes contact with an internal combustion engine, wherein the covering member prevents the fixing member from directly making contact with the top surface of the support member when the fixing member tightens the knock sensor to said internal combustion engine.