Aircraft piston engine magneto and ignition system

A magneto comprising:

• a housing;
• a rotor assembly mounted in the housing and comprising a magnetic rotor and at least one bearing that supports the rotor for rotation in the housing, the rotor assembly having a first end and a second end, with the rotor having a permanent magnet assembly located between the first and second ends, wherein the first end is externally accessible at an opening in the housing such that the rotor can be rotationally driven by an external drive component;
• and
• an ignition circuit comprising circuit components that include at least one power coil and position sensor each inductively coupled to the magnetic rotor, the ignition circuit including high voltage output terminals mounted at an externally accessible location of the housing;
• wherein the rotor assembly is a terminal mechanical device such that the rotor rotates within the housing without transferring its mechanical motion to any of the circuit components.

A magneto comprising a permanent magnet rotor, a ferromagnetic core positioned relative to the rotor to concentrate and guide changing magnetic field lines that extend between opposite magnetic poles of the rotor as the rotor spins, and an ignition circuit that inductively extracts power from the changing magnetic field lines, wherein the ignition circuit includes:

• a power circuit having a reconfigurable charging coil comprising a plurality of power coils that are wound about the core and that supply induced electrical power to one or more output nodes of the power circuit;
• a high voltage discharge circuit that is connected to the output node(s) of the power circuit and that generates high voltage spark energy at a plurality of high voltage output terminals;
• and
• a control circuit connected to and operable under power from at least one of the output nodes of the power circuit, wherein the control circuit includes control outputs connected to both the power circuit and discharge circuit, including at least one control output to the power circuit that electronically configures the power coils either in series or in parallel, and at least another control output connected to the discharge circuit that causes high voltage ignition pulses suitable for firing of a spark plug.

A magneto comprising a permanent magnet rotor, a ferromagnetic core positioned relative to the rotor to concentrate and guide changing magnetic field lines that extend between opposite magnetic poles of the rotor as the rotor spins, and an ignition circuit that inductively extracts power from the changing magnetic field lines, wherein the ignition circuit includes:

• a power circuit having a plurality of power coils that are wound about the core and that supply induced electrical power to one or more output nodes of the power circuit;
• a capacitive discharge ignition (CDI) discharge circuit having at least one ignition storage capacitor charged via the one or more output nodes, at least one ignition coil configured as a step up transformer having a primary and an inductively coupled secondary connected to one or more outputs of the CDI discharge circuit, and at least one controllable solid state switch, wherein the solid state switch and primary are series connected in circuit across the ignition storage capacitor such that, upon activation of the solid state switch, charge from the ignition storage capacitor flows through the switch and primary thereby establishing a magnetic field that remains until the solid state switch is deactivated, at which time current flow through the primary is interrupted so as to induce a high voltage pulse across the secondary;
• and
• a control circuit comprising at least one operating power storage capacitor, a position sensor located adjacent the magnetic rotor to detect magnetic field lines emanating from the rotor as it rotates, and a timing circuit that controls operation of the solid state switch based on rotor angular position sensed by the position sensor,
• wherein the operating power storage capacitor of the control circuit is connected to the ignition storage capacitor via a diode that permits charging of the operating power storage capacitor and prevents it from discharging by reverse current flow to the ignition storage capacitor, whereby the power coils provide operating power for both the ignition circuit and control circuit.