High Pressure Fitting Assembly Tool-Free Connection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing connectors for miniature fluid conduits in high-pressure liquid chromatography systems, such as HPLC and UHPLC, face challenges with extreme pressures, requiring wrenches for disconnection and often failing to maintain seals under elevated pressures, leading to dead volume issues.
Innovation Solution
A high-pressure liquid chromatograph fitting assembly featuring a first and second fitting with central passages, a retractable end fitting, and a biasing member to minimize dead space, along with pins to prevent rotation, allowing for secure and tool-free connection and disconnection without compromising seal integrity at high pressures.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If traditional threaded fittings are used to connect miniature fluid conduits in high-pressure liquid chromatography systems, then the connections can be made securely, but wrenches are required for disconnection and seal integrity cannot be maintained under elevated pressures
Solution Approach 1:
The fitting employs a dynamic quarter-turn mechanism where the actuator rotates to automatically tighten ferrules onto the fluid conduit, creating a secure seal without requiring external tools. The dynamic adjustment allows the ferrules to conform to the conduit surface, maintaining seal integrity under high pressure while enabling tool-free operation
Solution Approach 2:
Ferrules serve as intermediary elements between the fitting body and the fluid conduit. These ferrules are tightened by the actuator mechanism to create a reliable seal, transferring the sealing function from the main fitting components to specialized intermediary ferrule elements that are optimized for creating pressure-resistant seals
2Productivity
If conventional fittings are used in HPLC and UHPLC systems, then connections can be established, but dead volume issues arise that compromise fluid transfer efficiency
Solution Approach 1:
The design extracts and eliminates unnecessary internal volume from the fitting structure. The central passages are optimized to minimize dead space, and the retractable end fitting allows the fluid conduit to extend directly into the fitting body, removing extraneous volume that would otherwise create dead zones where fluid stagnation could occur
Solution Approach 2:
The retractable end fitting employs a nested configuration where the fluid conduit is inserted directly into the fitting body's central passage, and the actuator mechanism is housed within the fitting structure. This nesting minimizes the overall volume occupied by the connection assembly and eliminates dead space between components
3Adaptability or versatility
If standard threaded fittings are employed to connect analytical components, then various configurations can be achieved, but the connections require wrenches for assembly and disassembly
Solution Approach 1:
The fitting mechanism performs the tightening operation itself through the quarter-turn actuator, which automatically tightens the ferrules onto the fluid conduit as it rotates. This self-service mechanism eliminates the need for external wrenches or tools, making the fitting easy to operate while maintaining secure connections
Solution Approach 2:
The fitting design incorporates preliminary positioning features that guide the fluid conduit and ferrules into correct alignment before the tightening action occurs. The central passages and ferrule geometry are designed to automatically position components properly, so that the quarter-turn actuation simply secures the pre-positioned components without requiring manual alignment
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 enables secure, tool-free connections and disconnections at high pressures, minimizing dead volume and maintaining seal integrity, thus enhancing the reliability and efficiency of fluid transfer in high-pressure liquid chromatography systems.
Implementation Method 1
a biasing member extending between the housing and a washer disposed on the tube to allow selective positioning of the tube within the housing relative to the second end of the second fitting
Data Source
Figure 1
Figure 2
Figure 3
AI summary
An analytical instrument fitting assembly for coupling first and second analytical fluid conduits is provided. The fitting assembly includes a first fitting defining a central passage adapted to receive a first fluid conduit defining an internal diameter of no greater than 1.0160 mm (0.040 inch) and a second fitting. The second fitting defines a central passage extending between first and second ends and is in fluid communication with the first fitting.