Needle Port Segmented Guide Section for Leakage Prevention
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional needle ports in preparative separation-purification systems often experience liquid leakage due to misalignment between the needle and the needle port, causing the needle tip to scratch the tapered section and impede a tight attachment, leading to leakage.
Innovation Solution
A needle port design with a guide section having a larger inside diameter than the needle's outside diameter, a passage section with a smaller inside diameter than the needle's tapered portion, and a tapered section with a steeper angle than the needle's taper, ensuring correct alignment and preventing surface contact that could cause leakage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If a tapered section is provided in the needle port to guide the needle, then alignment is improved, but the needle tip scratches the tapered section surface causing liquid leakage
Solution Approach 1:
The in-port path is divided into three distinct sections: a guide section with large inside diameter for initial alignment, a tapered section with steep taper angle for precise positioning, and a passage section with small inside diameter for liquid-tight connection. This segmentation allows each section to perform its specific function without interfering with others, preventing surface scratching while maintaining alignment precision.
Solution Approach 2:
The guide section acts as an intermediary element between the needle tip and the tapered section. It provides a large-diameter pathway that guides the needle into correct alignment before the needle reaches the tapered section, preventing direct contact and surface scratching while still achieving precise alignment.
2Reliability
If the tapered section has a small width to prevent scratching, then liquid-tightness is improved, but alignment capability is reduced
Solution Approach 1:
The in-port path is divided into three distinct sections: a guide section with large inside diameter for initial alignment, a tapered section with steep taper angle for precise positioning, and a passage section with small inside diameter for liquid-tight connection. This segmentation allows each section to perform its specific function without interfering with others, preventing surface scratching while maintaining alignment precision.
Solution Approach 2:
The solution transitions from a single tapered path to a multi-sectional path with varying diameters. The guide section provides radial clearance in the radial dimension, allowing misaligned needles to enter without contact, while the tapered section provides axial positioning. This dimensional approach allows both alignment and liquid-tightness to be achieved simultaneously.
3Ease of operation
If the needle is driven by a motor with high precision, then operation accuracy is improved, but misalignment still occurs due to trap column placement errors
Solution Approach 1:
The guide section performs preliminary alignment action before the needle reaches the critical tapered section. By providing a large-diameter entry path, it pre-corrects misalignment caused by trap column placement errors, allowing the subsequently driven needle to engage the tapered section already in correct alignment and achieve liquid-tight connection.
Solution Approach 2:
The guide section provides a cushioning effect by absorbing misalignment errors through its larger diameter. It creates a tolerance zone that accommodates placement errors beforehand, preventing these errors from propagating to the tapered section and compromising the liquid-tight connection.
Data Source
AI summary
A liquid leakage between a needle and a needle port is prevented. To this end, a guide section, a passage section, and a tapered section are provided in an in-port path of a needle port. The guide section has an inside diameter larger than the outside diameter of a body of a needle. The passage section has an inside diameter smaller than the outside diameter of the body of the needle and larger than the tip diameter of a tapered portion of the needle. The tapered section connects the guide section and the passage section. The taper angle θ2 of the tapered section is set to be larger than the taper angle θ1 of the tapered portion of the needle, and the width w of the tapered section is set to be smaller than half the difference between the outside diameter of the body and the tip diameter of the needle.