Electronic Aircraft Magneto Ignition for Low-Speed Self-Powering
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Mechanical magnetos in aircraft piston engines require frequent recalibration and maintenance due to wear on components, leading to increased service burden and inefficiency at lower engine speeds, and mechanical solutions like impulse couplings and retard breakers either fail to address timing issues or require external power.
Innovation Solution
A fully electronic magneto system with a magnetic rotor and an ignition circuit that uses inductively coupled power coils to generate ignition energy at varying speeds without mechanical components, utilizing a reconfigurable charging coil and angular position sensor for precise ignition timing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If mechanical components (cam, contact breaker, distributor) are used in the magneto system, then the magneto can be mechanically driven and self-powered, but the components experience wear leading to timing inaccuracies and frequent maintenance requirements
Solution Approach 1:
The patent replaces mechanical components (cam, contact breaker, distributor) with electronic components (angular position sensor, electronic switch, electronic distributor). The angular position sensor detects rotor position without mechanical contact, and electronic switching elements replace the mechanical contact breaker, eliminating wear-related timing inaccuracies and reducing maintenance requirements.
Solution Approach 2:
The electronic magneto system is self-diagnosing and self-adjusting. The angular position sensor continuously monitors rotor position and the electronic control system automatically compensates for any deviations, maintaining accurate ignition timing without requiring external calibration or adjustment by maintenance personnel.
2Device complexity
If a fixed ignition timing is used in the magneto system, then the system is simpler to design and operate, but the engine efficiency is reduced at lower operating speeds
Solution Approach 1:
The patent implements variable ignition timing that dynamically adjusts based on engine operating conditions. The electronic control system modifies the ignition timing angle according to rotor speed and load conditions, optimizing combustion efficiency across the entire operating range while maintaining system simplicity through electronic control algorithms.
Solution Approach 2:
The system changes the ignition timing parameter dynamically based on operating speed. At low speeds, the timing is retarded to prevent premature ignition, while at optimal speeds, the timing is advanced to maximize efficiency. This parameter adjustment is achieved through electronic control without mechanical complexity.
3Reliability
If impulse coupling is used to address low-speed ignition timing, then the ignition timing is improved at startup speeds, but mechanical wear increases and the solution does not address power generation at low speeds
Solution Approach 1:
The patent replaces the mechanical impulse coupling with an electronic solution. The angular position sensor and electronic control system provide accurate ignition timing at all speeds without mechanical contact. Additionally, the electronic distributor and power coil design ensure sufficient electrical power generation even at low rotor speeds, addressing both timing and power generation issues simultaneously.
4Ease of repair
If retard contact breakers are used instead of impulse couplings, then mechanical wear is reduced, but external battery power and starting vibrator are required
Solution Approach 1:
The electronic magneto system is completely self-powered and self-starting. The power coils are inductively coupled to the rotor and generate electrical power internally without requiring external battery power or starting vibrators. The electronic components remain stationary and wear-free while providing reliable operation across all speed ranges through internal power generation.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The system provides self-powered ignition across a wide range of engine speeds without mechanical wear, eliminating the need for frequent recalibration and external power, ensuring reliable operation and reduced maintenance.
Implementation Method 1
the power coils are inductively powered off the magnetic rotor
Implementation Method 2
a secondary coil inductively coupled to the primary to provide a stepped up high voltage
Data Source
AI summary
An aircraft piston engine magneto having a magnetic rotor and an ignition circuit that includes a charging coil inductively coupled to magnetic poles of the rotor. The charging coil includes a plurality of power coils that are inductively powered off the magnetic rotor and that charge the ignition circuit during rotation of the rotor. One or more of the power coils are electronically utilized by the ignition circuit as a higher turn power coil when the rotor is running at low speeds and as a lower turn power coil when the rotor is running at higher speeds. The ignition circuit is a fully electronic ignition circuit that generates and distributes ignition pulses to the piston engine spark plugs using only non-mechanically actuated electrical components within the magneto.