Fuel Injector Retaining Clip Assembly for High-Pressure Connection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional fuel delivery systems face challenges with complex and costly manufacturing, large space requirements, and potential dislodgment of connections in high-pressure fuel delivery systems, necessitating a reliable, simple, and space-efficient connection between the fuel injector and injector cup.
Innovation Solution
A connection assembly featuring retaining pins and a C-shaped retaining clip that engages the pins within the injector cup, providing a robust and secure retention mechanism with minimal parts and low assembly force, utilizing a spring steel clip that can be easily formed and discarded for replacement.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional connection shapes and materials are used, then connection reliability may be improved, but manufacturing precision requirements increase
Solution Approach 1:
The patent changes the geometric parameters of the retaining clip, specifically incorporating a lead angle on the retention hooks and a helical midportion with specific pitch and radius of curvature. These parameter changes allow the clip to be installed with lower precision requirements while maintaining reliable retention of the fuel injector in the injector cup.
2Strength
If conventional connection designs are used, then connection strength may be improved, but device complexity increases
Solution Approach 1:
The retaining clip is segmented into three functional portions: retention hooks for engaging the fuel injector, a helical midportion for providing spring force and guiding installation, and ends for engagement with the injector cup. This segmentation allows each portion to perform its specific function efficiently, achieving strong retention with a relatively simple single-piece component.
3Reliability
If conventional connection methods are used, then assembly reliability may be improved, but ease of operation deteriorates
Solution Approach 1:
The retaining clip utilizes elastic deformation and spring force dynamics to facilitate assembly. The helical midportion acts as a spring that allows the clip to flex during installation and then provides continuous retention force. The lead angle on the hooks enables the clip to be leveraged against the injector cup sidewall to spread the clip for easy assembly without special tools.
4Reliability
If conventional connection assemblies are used, then retention reliability may be improved, but volume requirements increase
Solution Approach 1:
The retaining clip is designed to nest within the injector cup, with the helical midportion residing in a circumferential sidewall groove. The retention hooks engage with the fuel injector while the clip itself is contained within the injector cup envelope. This nesting arrangement provides reliable retention without requiring additional packaging space within the engine envelope.
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 offers a reliable, low-force assembly method with high retention force, eliminating rattle and loose connections, and reduces manufacturing complexity and assembly time while ensuring robust retention without special machining, suitable for high-pressure fuel delivery systems.
Implementation Method 1
The retaining clip contains a pitch bend 'coil spring' section shape that produces a de-coupled retention force perpendicular to the pin axial travel. This force 'springs' the clip between the top and bottom of a circumferential sidewall groove in the exterior of the injector cup.
Data Source
AI summary
A connection assembly is used to detachably connect fuel injector to an injector cup of a fuel rail. The connection assembly includes the injector cup that receives and supports the fuel injector, a pair of retaining pins that an configured to retain an inlet end of the fuel injector within a bore of the injector cup, and a retaining clip that retains the retaining pins in corresponding through holes provided in the injector cup. The retaining clip is C-shaped and partially encircles the injector cup such that a first end of the retaining clip extends into the through hole that receives the first pin, the second end of the retaining clip extends into the through hole that receives the second pin. The retaining clip is configured to prevent the pins from exiting the respective through holes and minimize assembly noise.