Fuel Pump Isolation Valves for Pressure Differential Elimination
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Fuel delivery systems with high-pressure fuel pumps often experience pressure differentials between fuel rails due to fuel pulsations, leading to undesirable pressure fluctuations and increased complexity in assembly and cost.
Innovation Solution
A high-pressure fuel pump assembly with dual output fuel paths and a main pressure relief path, including relief valves that restrict fuel flow between the paths to isolate the fuel rails, preventing pressure differentials and simplifying assembly.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If fuel rails are connected in series with a Y-block or cross-over line, then fuel delivery to multiple rails is achieved, but pressure differentials occur between fuel rails due to fuel pulsations
Solution Approach 1:
The fuel delivery system is segmented into separate pressure zones for each fuel rail. Individual isolation valves (first isolation valve in first fuel path, second isolation valve in second fuel path) are installed at the pump outlet to separate the pressure domains, preventing pressure pulsations from propagating between rails while maintaining independent fuel delivery capability.
Solution Approach 2:
Isolation valves serve as intermediary elements between the pump outlet and fuel rails. These valves act as mediators that block pressure pulsation transmission while allowing controlled fuel flow to each rail, thereby eliminating the direct pressure coupling that causes differentials in series connections.
2Object-affected harmful factors
If orifices are added to fuel feed lines and relief valve is included, then fuel pulsation attenuation is attempted, but pressure differentials between fuel rails still occur
Solution Approach 1:
The system segments the fuel delivery paths into isolated pressure zones using individual isolation valves for each rail. This segmentation prevents pressure pulsations from affecting both rails simultaneously, making additional pulsation attenuation measures less necessary while eliminating the root cause of pressure differentials.
Solution Approach 2:
The harmful pressure pulsations are extracted or blocked from propagating between fuel rails through the use of isolation valves. By removing the pressure coupling between rails, the system eliminates the mechanism that causes pressure differentials, rendering less effective pulsation attenuation methods insufficient.
3Stress or pressure
If fuel rails are isolated with individual relief paths and isolation valves, then pressure differentials are eliminated, but device complexity increases
Solution Approach 1:
The system merges the isolation valve functionality into the fuel pump assembly structure itself, where the first and second isolation valves are integrated at the pump outlet. This merging approach reduces the need for separate external isolation components and simplifies the overall system architecture while maintaining pressure differential elimination.
Solution Approach 2:
The isolation valves serve multiple functions: they isolate pressure pulsations between rails, control fuel flow distribution, and work in conjunction with individual relief paths to maintain pressure balance. This multi-functionality reduces the need for additional dedicated components, offsetting the complexity increase from adding isolation capability.
4Ease of operation
If multiple joints are used between high-pressure pump and fuel rails, then flexible connection is achieved, but assembly time and cost increase
Solution Approach 1:
The fuel pump assembly is designed with integrated fuel paths and isolation valves that directly connect to fuel rails, merging multiple connection points into a unified assembly structure. This integration reduces the number of separate joints and connection components, thereby decreasing assembly steps, time, and cost while maintaining connection flexibility through the integrated design.
Solution Approach 2:
The pump assembly is segmented into distinct functional modules (fuel paths, isolation valves, relief paths) that are pre-assembled and tested as a unit. This modular segmentation allows for simplified integration with fuel rails, reducing the complexity of on-site assembly compared to connecting multiple separate components individually.
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 solution effectively isolates fuel rails, reducing pressure rise times, material costs, and assembly complexity by preventing pressure differentials and allowing for reduced fuel rail volume and fewer joints between the pump and rails.
Implementation Method 1
A main pressure relief fuel path is in communication with the fuel pump chamber and includes a pressure relief valve. A first relief fuel path is in communication with both the first output fuel path and the main pressure relief fuel path. A second relief fuel path is in communication with both the second output fuel path and the main pressure relief fuel path. The first and the second relief fuel paths are configured to restrict fuel flow therethrough between the first and the second output fuel paths.
Data Source
AI summary
A fuel delivery system including a high pressure fuel pump assembly. The assembly includes first and second output fuel paths each in communication with a fuel pump chamber. A main pressure relief fuel path is in communication with the fuel pump chamber and includes a pressure relief valve. A first relief fuel path is in communication with both the first output fuel path and the main pressure relief fuel path. A second relief fuel path is in communication with both the second output fuel path and the main pressure relief fuel path. The first and the second relief fuel paths are configured to restrict fuel flow therethrough between the first and the second output fuel paths.