Solenoid Fuel Injector Closing Control with Timed Braking Pulses
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing fuel injectors for gaseous fuels face issues with wear and noise due to high impact speeds of moving parts, and existing methods for determining the closing time of the injector are inaccurate or require excessive processing resources, especially during transient conditions.
Innovation Solution
A method for controlling solenoid actuated fuel injectors that involves applying a chopped hysteresis pulse during recirculation control to detect the end of the pulse, which is used to determine the time the needle starts to close, allowing for a timed braking pulse to reduce wear and noise.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If a fixed or iteratively adapted braking pulse is applied after the end of fueling command, then the impact speed is reduced, but reopening events may occur in transient conditions
Solution Approach 1:
The patent implements feedback by detecting the actual closing response of the injector through monitoring the low side voltage inflection point, and using this detected closing time to dynamically adjust the braking pulse timing. This closed-loop approach ensures the braking pulse is applied at the optimal moment based on real injector behavior, preventing reopening events while effectively reducing impact speed.
Solution Approach 2:
The patent transitions from fixed or iteratively adapted braking pulse parameters to a dynamic timing mechanism that adapts to transient conditions in real-time. By continuously monitoring the injector closing response and adjusting the braking pulse timing accordingly, the system maintains optimal performance during cold crank, warm-up, and other transient operating conditions.
2Object-affected harmful factors
If mechanical or hydraulic damping is implemented at the injector closing, then the impact speed is reduced, but manufacturing effort and cost increase
Solution Approach 1:
The patent replaces mechanical or hydraulic damping systems with an electrical control solution. By using a solenoid actuator with precisely timed braking pulses controlled through electronic monitoring of the low side voltage, the system achieves impact speed reduction without the complexity and cost of mechanical dampers, hydraulic systems, or additional physical components.
3Measurement precision
If the closing detection is realized by searching the inflection in the injector low side voltage, then the closing time is determined, but detection becomes difficult at low pulse width due to fading out inflection
Solution Approach 1:
The patent introduces an intermediary signal processing approach that enhances the detectability of the closing inflection point. By applying signal processing techniques to the low side voltage waveform, the system can reliably detect the closing inflection even at low pulse widths where the inflection would otherwise fade out or become indistinguishable from noise.
4Adaptability or versatility
If look up tables and iterative adaptation are used to determine braking pulse parameters, then the parameters can be adjusted, but input parameters are not available fast enough or precise enough
Solution Approach 1:
The patent implements a self-service mechanism where the injector's own closing response, detected through real-time monitoring of the low side voltage inflection point, directly determines the braking pulse timing. This eliminates the need for external look-up tables or iterative adaptation processes, providing immediate and precise parameter adjustment based on the actual injector behavior without time delays.
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 method accurately determines the closing time of the injector, enabling a timed braking pulse to reduce wear and noise, improving injector lifespan and performance, especially in transient conditions.
Implementation Method 1
a solenoid actuator adapted to be energized during an energization phase so as to move a needle
Implementation Method 2
closing is typically driven by the core spring that accelerates a pintle back to closed position
Data Source
Figure 1
Figure 2A~3B
Figure 4A~4C
AI summary
A method of controlling a solenoid actuated fuel injector, said injector including a solenoid actuator adapted to be energized so as to move a pintle and needle arrangement, such that the needle moves away from a connected thereto, away from a valve seat to an open position, and including circuitry adapted to apply chopped hysteresis control subsequent to an energisation phase, comprising: a) obtaining a signal of the current or voltage across the solenoid; b) analyzing the voltage or current to detect a chopped hysteresis pulse c) determining the time point of the end of said chopped hysteresis pulse; d) applying a braking pulse to the solenoid, the timing of which is dependent on the results of step c).