Pressure Sensor Tip and Port Assembly for High-Pressure Fuel Injection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Internal combustion engines employing gasoline direct injection systems require precise pressure measurement of fuel injection, but existing pressure sensors lack accuracy and reliability in measuring high-pressure conditions effectively.
Innovation Solution
A pressure sensor design incorporating a port and tip assembly with a flexible section and micro-strain gauges, where the port contains a cavity and flexible section that flexes in response to pressure, allowing the gauges to measure strain and produce an output representing the pressure, secured through press-fitting or other methods for accurate measurement.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If existing pressure sensors are used for measuring high-pressure fuel injection, then the device complexity is low, but the measurement precision and reliability are insufficient
Solution Approach 1:
The pressure sensor is divided into distinct functional segments: a port assembly containing the cavity and flexible section, a separate tip component with sealing provisions, and integrated micro-strain gauge elements. This segmentation allows each component to be optimized for its specific function while maintaining overall measurement precision.
Solution Approach 2:
A flexible section made of elastomeric material is employed within the port cavity to convert pressure changes into measurable deformation. This flexible element works in conjunction with micro-strain gauges to achieve high measurement precision while maintaining a relatively simple overall structure.
2Measurement precision
If a flexible section with micro-strain gauges is used to measure pressure, then the measurement precision improves, but the reliability under high-pressure conditions deteriorates
Solution Approach 1:
The pressure sensor utilizes composite construction combining rigid port and tip components with a flexible elastomeric section. This composite approach allows the structure to withstand high pressures while the flexible section provides accurate measurement signals through controlled deformation.
Solution Approach 2:
The port cavity is designed with specific geometric features and the flexible section is pre-positioned to distribute high-pressure loads evenly. This preliminary structural design cushions the sensitive measurement elements from direct exposure to peak pressure stresses, maintaining reliability under high-pressure conditions.
3Manufacturing precision
If the port is secured to the tip through press-fitting, then the manufacturing precision is improved, but the ease of manufacture deteriorates
Solution Approach 1:
The sensor is manufactured as separate port and tip components that are subsequently assembled through press-fitting. This segmentation enables precise machining of each component independently while providing a standardized, repeatable assembly process that maintains manufacturing precision.
Solution Approach 2:
The press-fit interface acts as an intermediary connection between the port and tip, providing precise alignment and secure mechanical coupling. This intermediate connection method achieves high assembly precision through controlled interference fitting while maintaining reasonable ease of manufacture through standardized tolerances.
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 pressure sensor effectively measures fuel injection pressure with high precision, enabling more complete combustion, cooler cylinder temperatures, and increased efficiency and power in internal combustion engines.
Implementation Method 1
a flexible section which may flex (strain) based on the pressure
Implementation Method 2
one or more gauges (e.g., micro-strain gauges (MSGs)) that may measure the flexing of the flexible section
Data Source
AI summary
In an embodiment, a pressure sensor includes a tip secured to a port. The tip includes an opening for receiving pressure to be measured by the pressure sensor. The port includes a threaded section for mounting the pressure sensor in a fixture such as, for example, a rail. The port also includes a flexible section, a cavity, and an opening. The opening in the tip receives pressure from an outside source and channels the pressure to the opening of the port. The opening of the port receives the pressure from the tip and channels the pressure to the cavity. The pressure received in the cavity applies a force to the flexible section which flexes in response to the force. Moreover, forces are provided by the tip and the threaded section to keep the tip secured to the port.