High-Pressure Fuel Pump Solenoid Valve Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
High-pressure fuel pumps with normal close type solenoid valves face issues with continuous energization during engine operation modes like engine braking, leading to overheating and increased energy consumption, and inadequate pressure control in the common rail, affecting combustion stability and emission gas properties.
Innovation Solution
A control apparatus for high-pressure fuel pumps that adjusts the solenoid valve's energization timing and duty cycle based on engine conditions, ensuring optimal opening and closing control during charging and compression strokes, and limits the finish timing of the electric driving signal to a predetermined phase, reducing solenoid heat and energy consumption while maintaining high fuel pressure responsibility.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the solenoid valve is energized continuously to maintain valve opening state during engine braking, then fuel discharge is prevented and pressure is maintained, but the solenoid valve overheats and energy consumption increases
Solution Approach 1:
The control apparatus applies periodic action by controlling the solenoid valve to open and close in cycles during engine braking. Instead of continuous energization, the solenoid is activated only during specific periods (charging stroke and part of compression stroke), allowing periodic opening and closing that prevents fuel discharge while reducing energy consumption and preventing overheating.
Solution Approach 2:
The control apparatus applies preliminary action by opening the solenoid valve in advance during the charging stroke before the compression stroke begins. This preliminary opening allows the valve to be in the correct state at the start of compression, enabling controlled fuel discharge prevention without requiring continuous energization throughout the entire compression stroke.
2Reliability
If the solenoid valve is energized continuously during compression stroke, then fuel discharge is prevented, but the solenoid valve overheats
Solution Approach 1:
The control apparatus applies periodic action by limiting solenoid energization to specific periods (charging stroke and portion of compression stroke) rather than continuous operation. This periodic control maintains fuel discharge prevention reliability while allowing the solenoid to cool during non-energized periods, preventing overheating.
Solution Approach 2:
The control apparatus extracts the harmful continuous energization period from the compression stroke, removing excessive energization during the latter part of compression where it causes overheating. The solenoid is energized only when necessary for fuel discharge control, extracting the harmful thermal effect while maintaining the essential fuel discharge prevention function.
3Reliability
If the solenoid valve opening timing is not precisely controlled, then pressure control in common rail is unstable, but precise control requires complex timing mechanisms
Solution Approach 1:
The control apparatus applies feedback by using the cam angle sensor to detect the actual position of the pump driving cam and comparing it with predetermined values to determine precise opening and closing timings. This feedback mechanism enables accurate timing control based on real-time cam position information, stabilizing pressure control without requiring overly complex mechanical timing mechanisms.
Solution Approach 2:
The control apparatus replaces complex mechanical timing control with an electrical control system that uses sensor feedback. Instead of relying on purely mechanical linkages and cam profiles to control timing, the system uses the cam angle sensor to detect cam position and electronically controls the solenoid valve timing, simplifying the overall system while improving precision.
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
This solution reduces solenoid heat and energy consumption, enhances fuel system stability, and improves combustion and emission gas properties by optimizing the solenoid valve's operation, ensuring precise control over the high-pressure fuel pump's discharge rate.
Implementation Method 1
a solenoid valve which is installed as a suction valve in a fuel charging passage to the pressurized chamber such that a pump suction pressure generated in the pressurized chamber in the charging stroke is exerted on the solenoid valve in a valve opening direction, and that is closed at OFF state of an electric driving signal and opened at ON state of the electric driving signal
Data Source
AI summary
A control device for a high-pressure fuel pump for an internal combustion engine having a solenoid valve installed as a suction valve in a fuel charging passage to a pressurized chamber. A pump suction pressure generated in the pressurized chamber in the charging stroke is exerted on the solenoid valve in a valve opening direction. The solenoid valve is closed at OFF state of an electric driving signal and opened at ON state of the electric driving signal, so that a discharging rate of the high-pressure fuel pump of variable discharge rate type is controlled by an opening and closing control of the solenoid valve.