Abstract: A multi-layered cylinder head gasket for positioning between a cylinder head and a cylinder block of an engine includes upper and lower compression layers and a stopper layer. The compression layers and stopper layer all include apertures that mate together to define a peripheral edge. The stopper layer further includes a folded portion and a main body portion. The folded portion has a plurality of waves that contact the main body portion of the stopper layer to form a stopper when folded over. The stopper is positioned at the peripheral edge of the mated aperture. The waves deform under high compression loads generated by the joining of the cylinder head and the cylinder block. The deformation balances the stresses generated by the compression loads around the mated aperture.

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.

Abstract: A multi-layer steel (MLS) cylinder head gasket containing fully integrated pressure sensors includes first and second metal layers with inner facing surfaces, and a spacer layer interposed between the facing surfaces. Outer (non-facing) surfaces of the first and second metal layers each include an elastomeric seal coating; the inner surfaces of the layers each include a friction reducing coating. Combustion apertures extend fully between the outer surfaces of the gasket, and are adapted to circumscribe cylinder bores of an engine. The spacer layer includes protective slots positioned adjacent each of the combustion apertures. Each slot wall contains a pressure sensor in form of a strain gauge to measure deflection of the wall resulting from pressure changes within engine combustion chambers. The measured deflections are correlated to actual pressures within the chambers. In the protective slots, the strain gauges are not exposed to combustion gases that could otherwise foul the sensors.

Abstract: A multi-layered cylinder head gasket for positioning between a cylinder head and a cylinder block of an engine includes upper and lower compression layers and a stopper layer. The compression layers and stopper layer all include apertures that mate together to define a peripheral edge. The stopper layer further includes a folded portion and a main body portion. The folded portion has a plurality of waves that contact the main body portion of the stopper layer to form a stopper when folded over. The stopper is positioned at the peripheral edge of the mated aperture. The waves deform under high compression loads generated by the joining of the cylinder head and the cylinder block. The deformation balances the stresses generated by the compression loads around the mated aperture.

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.

Abstract: A cylinder head gasket has a multi-layered steel body that includes a unitary metallic stopper layer interposed between beaded outer layers. The interposed stopper layer has an asymmetrically formed bead defining at least one raised structure that circumferentially and closely surrounds a combustion aperture. Specifically, the bead defines a trough having a series of variations of thickness or widths about its circumferential dimension. An epoxy resin material substantially fills the volume of the trough about its circumferential extent, irrespective of the variable trough depth or width. In the disclosed embodiment, a metal/epoxy hard coating material is placed in and cured in the trough.