Patent ID: 6348797
Filing Date: 2002-02-19
Classification: F02P,H01F

Abstract:
A combustion state detecting apparatus for an internal combustion engine, comprising:a transformer including a primary winding and a secondary winding electromagnetically coupled such that upon interruption of a current flowing through said primary winding, a high voltage is induced at a high-potential end of said secondary winding; switching means (12) having a relatively high heat tolerance level for controllably interrupting the current flowing through said primary winding; a spark plug for generating a spark discharge in response to application of the high voltage making appearance at the high-potential end of said secondary winding; bias means (13) having a relatively low heat tolerance level for applying a voltage of positive polarity to a low-potential end of said secondary winding of said transformer to implement the detection of ions produced when the spark discharge occurs at said spark plug; and an outer packaging case for accommodating therein said transformer, said switching means and said bias means, wherein said bias means is disposed within said outer packaging case at a location adjacent to said switching means and remote from said transformer, with said switching means being interposed between said transformer and said bias means, and wherein said outer packaging case is filled with a moldable resin.