Movable Shield Syringe Assembly for Controlled Needle Penetration
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing syringe needles with lengths of 4-5 mm are difficult to insert into vials and aspirate due to their short length, and there is a need for improved devices to control the depth of needle penetration for delivering drugs to a selected target area.
Innovation Solution
A syringe assembly with a movable shield that slides or rotates relative to the syringe body, allowing the needle to be exposed in different lengths for filling and injecting, with the second exposed length being less than the first to control penetration depth.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If the needle length is increased to facilitate insertion into vials and aspirating, then the ease of filling and aspirating is improved, but the depth of penetration into the patient increases causing excessive discomfort and potential damage
Solution Approach 1:
The shield member is designed to be movable relative to the syringe barrel, allowing it to transition between a retracted position during filling/aspirating (exposing the full needle length) and an extended position during injection (covering part of the needle to limit penetration depth). This dynamic adjustment resolves the contradiction by providing different effective needle lengths for different operational phases.
2Object-affected harmful factors
If the needle length is decreased to limit penetration depth and reduce patient discomfort, then the harmful factors are reduced, but the ease of insertion into vials and aspirating deteriorates
Solution Approach 1:
The movable shield member allows the system to dynamically adjust the effective needle length based on the operational phase. During filling and aspirating, the shield is retracted to expose the full needle length for easy vial access. During injection, the shield extends to cover part of the needle, limiting penetration depth and reducing patient discomfort.
3Ease of operation
If a fixed long needle is used to ensure adequate penetration into vials, then the ease of filling is improved, but the control over injection depth deteriorates
Solution Approach 1:
The movable shield member transforms a fixed-length needle into a dynamically adjustable effective length system. The shield can be positioned to expose different lengths of the needle, providing precise control over injection depth while maintaining full needle exposure for easy vial filling and aspirating.
Data Source
AI summary
A syringe assembly (10, 80, 132, 192) includes a syringe barrel (12, 86, 134, 194) having a proximal end and a distal end, a needle (18, 89, 140, 200) coupled to the distal end of the syringe barrel, a body (22, 142, 202) coupled to the syringe barrel, and movable shield (24, 82, 164, 222) for moving in an axial direction between a first position where the needle is exposed and a second position covering at least a portion of the needle. The body (22, 142, 202) is configured for enabling the shield (24, 82, 164, 222) to move to the second position and retain the shield in the second position. The shield (24, 82, 164, 222) can slide axially, and rotate relative to the body or slide transversely relative to the body when the shield is in the second position.