DEVICE FOR DETECTING ELECTRIC IGNITION SIGNAL FROM COIL ON PLUG OF INTERNAL COMBUSTION ENGINE, DIAGNOSING DEVICE USED FOR ANALYZING THE SIGNAL, AND SIGNAL MEASURING METHOD

摘要

PROBLEM TO BE SOLVED: To provide a device for measuring an ignition charging signal generated by a coil of a coil on plug device of an internal combustion engine. SOLUTION: This signal detector 12 is provided with an insulating substrate having a first flat conductive layer on a first surface and a second flat conductive layer on a second surface. The first layer is connected to a signal wire, and the second layer is connected to an earthing wire. When the signal detector 12 is held in close contact with a coil 4 of the coil on plug 2, an ignition signal generated by the coil 4 to pass a plug 6 is detected. The detected signal is displayed and analyzed by connection to the signal analyzer. The amplitude of the signal output by the signal detector is controlled to various coils having different output signal strength by varying the surface area ratio of the first layer to the second layer.