Abstract: An ignition coil has concentrically arranged components including a core, a secondary winding spool adjacent to the core, a secondary winding wound on the spool, a case made of electrical insulating material, a primary winding wound on an outer surface of the case, and a shield disposed radially outwardly of the primary winding. The case is configured so as to allow the primary winding to be wound thereon and to space the shield a predetermined space from the primary winding. A radially inner surface of the case and a radially outer portion of the secondary winding define a single potting channel for receiving an epoxy potting material. The configuration eliminates the primary winding spool, which reduces material cost, and further eliminates the effective dielectric contribution of the primary winding spool for reduced capacitance to thereby provide improved secondary winding output.

Abstract: 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.

Abstract: An ignition coil is secured to an internal combustion engine by a twist lock connection. The twist lock connection is defined by a first connection feature comprising a plurality of tabs extending radially outwardly from a cylindrical body portion of the ignition coil, and a second connecting feature comprising a corresponding plurality of camming surfaces having a ramp shape and terminating in a mechanical stop.