Multi-Bevel Hypodermic Needle Tip for Reduced Injection Pain
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Solution Overview
Problem
Existing hypodermic needle tip geometries vary in penetration force and pain perception, leading to user preferences and discomfort during injections, with a need for improved designs that balance these factors.
Innovation Solution
A multi-beveled needle tip geometry with proximal, intermediate, and distal bevels, featuring smooth transitions between bevels and the lumen and outer periphery, formed through specific inclination angles and rotational adjustments, to create a more efficient and comfortable injection experience.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If a conventional single-bevel needle tip geometry is used, then the needle structure is simple and easy to manufacture, but the penetration force is high and pain perception is increased
Solution Approach 1:
The needle tip is segmented into multiple bevels (first bevel, second bevel, third bevel) with different inclination angles instead of using a single bevel. This segmentation allows each bevel to contribute differently to the penetration process, distributing the penetration force and reducing the peak force required, while still being manufacturable through conventional grinding processes.
Solution Approach 2:
Different portions of the needle tip are given different geometric properties through the multi-bevel design. The first bevel has a smaller inclination angle for initial penetration, while the second and third bevels have larger inclination angles for structural support and medication delivery, creating local quality variations that optimize both comfort and function.
2Ease of manufacture
If a conventional single-bevel needle tip geometry is used, then the manufacturing process is simple, but the injection comfort and pain perception are reduced
Solution Approach 1:
The needle tip is segmented into multiple bevels (first bevel, second bevel, third bevel) with different inclination angles instead of using a single bevel. This segmentation allows each bevel to contribute differently to the penetration process, distributing the penetration force and reducing the peak force required, while still being manufacturable through conventional grinding processes.
Solution Approach 2:
Different portions of the needle tip are given different geometric properties through the multi-bevel design. The first bevel has a smaller inclination angle for initial penetration, while the second and third bevels have larger inclination angles for structural support and medication delivery, creating local quality variations that optimize both comfort and function.
3Force
If a multi-beveled needle tip geometry is implemented, then the penetration force is reduced and injection comfort is improved, but the device complexity increases
Solution Approach 1:
The needle tip is segmented into multiple bevels (first bevel, second bevel, third bevel) with different inclination angles instead of using a single bevel. This segmentation allows each bevel to contribute differently to the penetration process, distributing the penetration force and reducing the peak force required, while still being manufacturable through conventional grinding processes.
Solution Approach 2:
The inclination angles of the bevels are specifically optimized (first bevel: 5-15 degrees, second bevel: 20-30 degrees, third bevel: 35-45 degrees) to achieve the desired balance between penetration force reduction and structural integrity. These parameter changes are implemented within conventional manufacturing capabilities.
Data Source
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AI summary
A multi-beveled needle point geometry for hypodermic needles such as pen needles. A proximal bevel is formed at a first angle of inclination, a pair of intermediate bevels at a second angle of inclination, and a pair of distal bevels at a third angle of inclination and differing angles of rotation. The second angle of inclination is substantially different than the first angle of inclination to define a marked apex at the intersections between the proximal bevel and the intermediate bevels. At least one smooth transition is typically provided between adjacent bevels, between a bevel and an outer surface of the needle, and/or between a bevel and the lumen of the needle.