Abstract: Sensor apparatus for a multiple layer steel (MLS) cylinder head gasket measures combustion pressures for detecting engine conditions. A membrane is positioned at one end of an elongated metal tube, and the membrane end of the tube engages a cylinder bore boundary. A fiber optical sensor apparatus is fixed within the tube, and communicates with cyclic combustion events via the membrane. In one disclosed embodiment, optical wires from sensor apparatus situated at each engine bore are bundled into a common groove machined into an extended spacer layer radially outwardly of the conventional boundary of the gasket. The tube protects the sensor apparatus from damage of sealing stress on the gasket, and particularly at the bore perimeter. Each tube lies in a separate groove in the spacer layer that terminates at the bore boundary. A converter changes optical signals received from the apparatus into electrical signals for transmittal to a controller.

Abstract: An improved fluid flow sensor for measuring changes in temperatures of fluids flowing through apertures of a multiple-layered gasket is embedded between layers of the gasket. A thermal resistor type of sensor based upon hotwire anemometer technology in a preferred embodiment is responsive to changes in fluid temperature and flow velocity. A primary resistance with external current leads and separate auxiliary leads for voltage sensing are employed, wherein changes in resistance are virtually linearly proportional to changes in temperature. A four-point probe measurement method provides a most accurate reading of the temperature data to the extent that resistance associated with lead and contact resistances are minimized. The thermal resistor sensor is constructed of relatively thin layers of dielectric and electrically conducting materials having a low thermal mass, wherein the dielectric layers serve as support and electrical insulation to protect the sensor from environmental deterioration.

Abstract: An improved fluid flow sensor for measuring changes in temperatures of fluids flowing through apertures of a multiple-layered gasket is embedded between layers of the gasket. A thermal resistor type of sensor based upon hotwire anemometer technology in a preferred embodiment is responsive to changes in fluid temperature and flow velocity. A primary resistance with external current leads and separate auxiliary leads for voltage sensing are employed, wherein changes in resistance are virtually linearly proportional to changes in temperature. A four-point probe measurement method provides a most accurate reading of the temperature data to the extent that resistance associated with lead and contact resistances are minimized. The thermal resistor sensor is constructed of relatively thin layers of dielectric and electrically conducting materials having a low thermal mass, wherein the dielectric layers serve as support and electrical insulation to protect the sensor from environmental deterioration.

Abstract: Sensor apparatus for a multiple layer steel (MLS) cylinder head gasket measures combustion pressures for detecting engine conditions. A membrane is positioned at one end of an elongated metal tube, and the membrane end of the tube engages a cylinder bore boundary. A fiber optical sensor apparatus is fixed within the tube, and communicates with cyclic combustion events via the membrane. In one disclosed embodiment, optical wires from sensor apparatus situated at each engine bore are bundled into a common groove machined into an extended spacer layer radially outwardly of the conventional boundary of the gasket. The tube protects the sensor apparatus from damage of sealing stress on the gasket, and particularly at the bore perimeter. Each tube lies in a separate groove in the spacer layer that terminates at the bore boundary. A converter changes optical signals received from the apparatus into electrical signals for transmittal to a controller.