SPARK IGNITION DEVICE PROVIDED WITH PIEZOELECTRIC ELEMENT

摘要

PURPOSE:To make the promotion of high energy by multidischarge attainable, by installing an electrode in an end face of a columnar piezoelectric element, while impressing an alternating voltage on one side of this electrode and connecting the other side electrode to a discharge gap in an electrical manner. CONSTITUTION:A signal adjusted to a resonant period of an engine speed and a PZT piezoelectric element is generated out of a control circuit 5. This signal is impressed on a piezoelectric element 2 through an electrode terminal 341 and a conductor 34. The piezoelectric element 2 is of input voltage consisting of 800V or so, generating a voltage of about 20-30kV as the output. This voltage is impressed on a spark plug 4 via a spring 344, a stem 343 and a stem holder 35. Thus, the promotion of high energy is attainable owing to multidischarge.