Fuel Injection Valve Flat Plane Geometry and Inclined Holes
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing fuel injection valves suffer from variations in flow rate accuracy and spray characteristics due to machining errors and valve element inclination, leading to excessive spray diffusion and reduced directivity, which can cause engine output degradation and exhaust gas issues.
Innovation Solution
The fuel injection valve design features injection holes arranged inside an imaginary envelope along the intersection of the valve seat and injection hole plate, with a flat plane at the valve element's end, and a projection extending parallel to the valve element, ensuring the vertical distance between the flat plane and injection hole plate is less than the hole diameter, and the holes are inclined, enhancing fuel flow and reducing spray diffusion.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the cavity height is increased to improve fuel flow and atomization, then atomization is enhanced, but flow rate accuracy and spray characteristics vary due to machining errors and valve element inclination
Solution Approach 1:
The patent changes the geometric parameters of the injection system by specifying precise relationships between the cavity height (h) and injection hole diameter (d) with h/d = 0.05 to 0.15, and positioning injection holes within an imaginary envelop defined by the valve seat extension and injection hole plate intersection. This parameter optimization ensures improved atomization while maintaining flow rate accuracy despite manufacturing variations.
Solution Approach 2:
The patent establishes a feedback mechanism through the geometric relationship where the cavity height automatically adjusts relative to the injection hole diameter and valve element position. The imaginary envelop construction provides a self-regulating system that compensates for machining errors and valve inclination, ensuring consistent spray characteristics.
2Manufacturing precision
If the cavity height is decreased to maintain flow rate accuracy, then manufacturing precision is improved, but atomization is insufficient
Solution Approach 1:
The patent optimizes the cavity height parameter within a specific range (h/d = 0.05 to 0.15) that simultaneously achieves good atomization and flow rate accuracy. This parameter selection represents the optimal compromise point where sufficient cavity volume for fuel flow is maintained while limiting height to reduce sensitivity to manufacturing variations.
3Productivity
If the spray diffusion is increased to improve fuel-air mixing, then atomization is enhanced, but spray directivity is deteriorated causing wall adhesion and liquid film formation
Solution Approach 1:
The patent applies local quality by creating a concentrated zone of fuel injection within the imaginary envelop, where the injection holes are positioned to deliver fuel precisely to the target region. The cavity structure provides localized fuel accumulation and controlled diffusion, ensuring good atomization while maintaining spray directionality and preventing wall adhesion.
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 design enhances atomization while maintaining flow rate accuracy and spray directivity, reducing excessive spray diffusion and improving engine performance by ensuring consistent fuel injection characteristics.
Implementation Method 1
a valve element for opening and closing a valve seat and being driven upon reception of an operation signal from a control unit and causing fuel to be injected from a plurality of injection holes
Implementation Method 2
the valve element is formed at a distal end thereof with a flat plane which is substantially parallel with the injection hole plate, wherein injection hole entrances of the injection holes are arranged inside an imaginary envelop along an intersection between an extension of a downstream inner wall of a seat portion of the valve seat and an upstream plane of the injection hole plate
Data Source
AI summary
A fuel injection valve in which a valve element is formed at a distal end thereof with a flat portion 13c which is substantially parallel with an injection hole plate 11, injection hole entrances 12a are arranged inside an imaginary envelop 15 along an intersection between an extension 10b of a downstream inner wall of a seat portion of a valve seat and an upstream plane 11c of the injection hole plate and outside the flat plane at the distal end of the valve element, and the relation between the vertical distance h between the flat plane at the distal end of the valve element and the upstream plane of the injection hole plate with the valve opened and the diameter d of the injection hole entrance is h<d, and the injection hole 12 is formed to be inclined by a predetermined angle with respect to the direction of the thickness of the injection hole plate.