Pressure sensor for combustion engine cylinders has spring membrane with low expansion external coating to create bi-metallic error compensation effect

摘要

A pressure sensor has a glass fibre adaptor base (43) holding a concave Platinum, Titanium, Nickel or Silicon alloy spring membrane with an internal polished light reflecting layer protected by an inert transparent Silica or Alumina layer and an external gold or platinum layer with lower thermal expansion coefficient.