Common-Rail Fuel Injection Valve Pressure Stabilization
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Common-rail fuel injection devices experience fuel pressure fluctuations, leading to variations in the amount of fuel injected and particle diameter, affecting the efficiency of fuel injection and combustion in internal combustion engines.
Innovation Solution
The design includes fuel supply pipes and injection-valve connection pipes with equal sectional areas and lengths, which helps mitigate fuel pressure fluctuations by ensuring similar characteristics across all fuel injection valves, allowing for shared fuel injection period adjustment maps and reduced adaptation steps.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If fuel is injected from a fuel injection valve, then fuel injection pressure increases and particle diameter is reduced, but injection-valve fuel pressure is temporarily decreased causing variations in subsequent fuel injection amount
Solution Approach 1:
The system is divided into multiple fuel supply paths (first fuel supply path and second fuel supply path) that are connected in parallel to the injection valve. This segmentation allows fuel to be supplied through multiple independent channels, preventing pressure fluctuations in one path from affecting the other paths, thereby maintaining stable injection pressure and consistent fuel injection amount.
Solution Approach 2:
A communication path is introduced between the first and second fuel supply paths, allowing pressure equilibrium and fuel flow compensation. When pressure fluctuates in one path, fuel can flow through the communication path to balance the pressure, acting as an intermediary that stabilizes the overall injection pressure without requiring changes to the common rail system.
2Reliability
If multiple fuel supply ports are used per injection valve, then fuel pressure fluctuation is reduced, but device complexity increases due to additional connection pipes
Solution Approach 1:
The communication path serves multiple functions: it balances pressure between fuel supply paths, enables fuel flow compensation, and maintains pressure equilibrium during multi-stage injection operations. This multi-functional design achieves pressure stabilization without requiring separate control systems or additional complex components for each function.
Solution Approach 2:
The communication path merges the first and second fuel supply paths into a unified pressure equilibrium system. By combining these paths through the communication path, the system achieves coordinated pressure management across multiple supply channels, reducing overall complexity compared to having completely independent control systems for each path.
3Productivity
If fuel pressure fluctuation occurs, then multi-stage injection timing is affected, but increasing fuel supply capacity to prevent fluctuation increases system complexity
Solution Approach 1:
The communication path is pre-established between fuel supply paths before injection operations begin. This preliminary configuration enables automatic pressure equalization and fuel flow compensation to occur naturally during multi-stage injection, eliminating the need for active pressure control systems or real-time adjustments that would increase system complexity.
Solution Approach 2:
The fuel supply system performs self-regulation of pressure fluctuations through the communication path without requiring external control intervention. When pressure fluctuates in one path, the system automatically compensates through fuel flow via the communication path, enabling self-service pressure stabilization that maintains multi-stage injection efficiency without adding complex control mechanisms.
Data Source
AI summary
A common-rail fuel injection device for an internal combustion engine, including fuel injection valves each having two fuel supply ports, is known as a fuel injection device for suppressing temporary decrease of a fuel pressure immediately after the end of fuel injection from the fuel injection valve. Even in this fuel injection device, the fuel injection pressure may fluctuate immediately after the end of fuel injection, thereby causing changes of amount and particle diameter of injected fuel. A common rail is connected to one fuel supply port of the fuel injection valve, whereas another fuel injection valve, which is non-contiguous in the order of combustions, is connected to the other fuel supply port by an injection-valve connection pipe.