Ignition Control Apparatus Stabilizing Combustion via Auxiliary Power Supply
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing ignition control apparatuses for internal combustion engines face issues such as energy inefficiency, increased size and manufacturing cost, and reliability concerns due to the use of high-voltage resistive devices, leading to flame blow-off and energy loss during spark discharge.
Innovation Solution
An ignition control apparatus that employs a step-up circuit, energy storage coil, and switching devices to manage energy flow efficiently, using a low-voltage input to the primary winding of the ignition coil, and an auxiliary power supply with a soft-off circuit to maintain spark discharge and stabilize combustion.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If a plurality of discharges are developed intermittently in one combustion stroke, then the spark discharge current will be zero a number of times between start and end of discharge, but this causes flame blow-off and loss of ignition energy
Solution Approach 1:
The patent applies continuous discharge method where the spark discharge current flows continuously from the start to the end of the discharge period without becoming zero. This is achieved by controlling the ignition coil to maintain a continuous current flow, preventing flame blow-off and ensuring stable combustion while effectively utilizing ignition energy.
2Reliability
If two parallel-connected ignition coils are used to maintain continuous spark discharge current, then the discharge current will not be zero, but the structure becomes complicated and the size increases
Solution Approach 1:
The patent segments the discharge process into two phases: a first discharge period using the ignition coil alone, and a second discharge period where an auxiliary power supply is connected in parallel to the ignition coil. This segmentation allows continuous current flow without requiring two permanently parallel-connected ignition coils, thus maintaining combustion stability while simplifying the overall structure.
Solution Approach 2:
The auxiliary power supply is prepared in advance and connected in parallel to the ignition coil at a specific timing during the discharge process. This preliminary preparation allows the system to transition smoothly to continuous discharge mode without requiring complex permanent dual-coil structures.
3Duration of action of moving object
If auxiliary voltage is applied to the secondary coil, then the discharge duration is extended, but a high voltage resistant circuit is required which increases size and manufacturing cost
Solution Approach 1:
The patent introduces a switching device as an intermediary component that controls the connection between the auxiliary power supply and the ignition coil. This switching device manages the parallel connection during the second discharge period, extending discharge duration while avoiding the need for complex high-voltage resistant circuits throughout the entire system.
4Reliability
If high voltage resistant devices are used in the DC-DC converter, then voltage resistance and heat dissipation are improved, but manufacturing cost and size increase
Solution Approach 1:
The auxiliary power supply operates periodically, being connected in parallel to the ignition coil only during the second discharge period when additional energy is needed. This periodic operation allows the use of less expensive power supply components that do not require continuous high-voltage resistance, reducing manufacturing cost while maintaining reliability when needed.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
An ignition control apparatus for engines is provided. The ignition control apparatus is designed to control a switch to release energy stored in a capacitor during spark discharge, thereby supplying a primary current to an other end side opposite a one end of a primary winding of an ignition coil connected to a dc power supply. This provides the ignition control apparatus which is capable of minimizing an increase in size or manufacturing cost and stabilizing the state of combustion of an air-fuel mixture.