Adjustable Needle Assembly Depth Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing needle assemblies for medical injections lack effective depth adjustment and sealing mechanisms, particularly for shallow injections like intradermal injections, where fluid leakage can occur due to built-up pressure and blister formation.
Innovation Solution
A needle assembly with a movable body and hub system that allows for adjustable depth settings, utilizing a pressure-sensitive adhesive to maintain the body's position on the skin during injection, enabling the needle to be inserted to a first depth and then adjusted to a shallower depth for improved sealing and fluid administration.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a fixed depth stop is provided on the needle assembly, then injection depth control is improved, but adaptability to different injection depths is worsened
Solution Approach 1:
The needle assembly employs a dynamic depth stop mechanism where the body can be repositioned along the hub to different locations. The depth stop is not fixed but can be adjusted to multiple positions, allowing the same device to provide precise depth control for different injection depths (e.g., intradermal, subcutaneous, intramuscular). This transforms a static component into a dynamic one that adapts to various clinical needs while maintaining precise control.
Solution Approach 2:
The invention changes the parameter of depth stop position from a fixed value to an adjustable variable. By allowing the body to be repositioned to different locations on the hub, the effective injection depth can be modified while maintaining the hard stop function. This parameter change enables the device to accommodate different injection depth requirements without sacrificing depth control precision.
2Adaptability or versatility
If the body is made movable relative to the hub, then depth adjustment capability is improved, but device complexity is worsened
Solution Approach 1:
The needle assembly is segmented into distinct functional components: the hub, the body, and the depth stop. The body is separated from the hub and can be independently repositioned, allowing depth adjustment without complicating the overall structure. This segmentation enables the movable body to provide depth adjustment capability while keeping each component relatively simple in design.
Solution Approach 2:
The body is disposed on the hub in a nested arrangement where the body can slide or move along the hub structure. This nesting allows the movable body to be integrated within the existing hub geometry, providing depth adjustment functionality without adding significant external complexity to the device. The nested configuration space-efficient and maintains a compact overall structure.
3Reliability
If adhesive is applied to the body for skin attachment, then sealing is improved, but skin discomfort is worsened
Solution Approach 1:
The adhesive properties of the body surface are optimized to provide sufficient sealing force during injection while minimizing skin irritation. By carefully selecting adhesive materials and controlling adhesive parameters (such as adhesive strength, thickness, and composition), the device achieves reliable sealing to prevent fluid leakage without causing excessive skin discomfort or irritation during and after the procedure.
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 adjustable needle assembly ensures precise depth control and enhanced sealing during injections, minimizing fluid leakage and discomfort by allowing the needle to be inserted to a first depth and then adjusted for shallower administration, thereby improving the efficacy of medical injections.
Implementation Method 1
a pressure sensitive adhesive disposed on the distal end of the body. The body is releasably retainable in a first position on the hub where the distal end of the needle extends distally a first distance from the distal end of the body. Also, the body is retainable in a second position on the hub where the distal end of the needle extends distally from the distal end of the body less than the first distance from the distal end of the body. The adhesive is configured to provide sufficient adherence to a patient's skin during an injection such that the body remains relatively fixed to the patient's skin to permit proximal movement of the hub relative to the body with the body being moved from the first position to the second position.
Data Source
AI summary
In one aspect, a needle assembly is provided herein which includes a hub; a needle fixed to the hub, the needle having a proximal end and a distal end, the distal end formed for insertion into a patient; and, a body disposed on the hub so as to be moveable relative thereto, the body having a distal end with an aperture formed therein configured to permit passage therethrough of the needle. The body is releasably retainable in a first position on the hub where the distal end of the needle extends distally a first distance from the distal end of the body. Also, the body is retainable in a second position on the hub where the distal end of the needle extends distally a second distance from the distal end of the body, the second distance being less than the first distance. The hub is displaceable proximally relative to the body to urge the body from the first position to the second position. Advantageously, with the subject invention, a needle assembly is provided which may provide a stop for a needle injection to a first depth, with the stop being adjustable to permit the injection to be conducted at a shallower, second depth.