초록 ▼

An ignition coil, spark plug, and pressure sensor for an internal combustion engine are integrated into a single assembly and mounted directly on a plug hole of an internal combustion engine. A hard spark plug shell serves as a magnetostrictive section for pressure detection. A radially polarized bi

An ignition coil, spark plug, and pressure sensor for an internal combustion engine are integrated into a single assembly and mounted directly on a plug hole of an internal combustion engine. A hard spark plug shell serves as a magnetostrictive section for pressure detection. A radially polarized biasing magnet is disposed adjacent the spark plug shell thereby generating an initial flux through a sensing winding. The sensing winding is wound about the lower end of the coil case to sense changes in the induction characteristics of the spark plug shell as a result of pressure changes in the cylinder. A first passive method of sensing pressure whereby the flux change due to the permeability change generates a signal voltage in the sensed coil. This voltage is proportional to the time rate of change of pressure which is integrated to produce a cylinder pressure waveform. A second active method employs an oscillator to drive the sensing circuit with a frequency at least ten times that of the pressure signal content. The frequency or amplitude of this signal is then modulated in response to the induction property change of the spark plug shell the induction changes The second method is capable of detecting both static and dynamic pressure.

대표청구항 ▼

[ What is claimed is:] [1.] A spark plug coil and pressure sensor assembly for providing a spark to a cylinder of an internal combustion engine and measuring pressure characteristics within said cylinder, said assembly comprising:an outer housing;a control circuit interface portion connected to a fi

[ What is claimed is:] [1.] A spark plug coil and pressure sensor assembly for providing a spark to a cylinder of an internal combustion engine and measuring pressure characteristics within said cylinder, said assembly comprising:an outer housing;a control circuit interface portion connected to a first end of said outer housing;at least one coil disposed within said outer housing, said at least one coil adapted to be connected to a voltage source through said interface to selectively energize said at least one coil;a spark plug shell connected to a second end of said outer housing and electrically connected to said at least one coil, said spark plug shell adapted to provide a spark when said at least one coil is energized;a pressure sensor assembly connected to said outer housing proximate said spark plug shell, said pressure sensor adapted to sense pressure changes in said cylinder, said pressure assembly including a sensing winding wrapped around a sensing spool formed on a coil case disposed within said outer housing, said sensing winding being connected to said circuit control interface via a flex circuit;wherein, said outer housing, said control circuit interface portion, said at least one coil, said spark plug shell and said pressure assembly are formed as an integrated assembly.