Active Triggering Withdrawal Mechanism for Injection Device
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing injectors with multiple automatic functions face challenges in achieving robustness, reliability, and low production costs, often resulting in medicament spillage and inaccurate dosages due to overestimated safety margins and unreliable retraction mechanisms.
Innovation Solution
An injector with an active triggering withdrawal mechanism that allows user-controlled needle withdrawal, ensuring complete dosages and preventing early or malfunctioning retraction, featuring a housing with a needle shield, activation means for penetration, injection means for automatic medicament delivery, and a retraction mechanism triggered by device removal from the injection site.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Extent of automation
If an automatic retraction mechanism is used, then the device achieves higher automation and functionality, but the reliability of needle retraction timing becomes uncertain due to component tolerances
Solution Approach 1:
The device uses the user's own removal action of the injector from the injection site as the triggering mechanism for needle retraction. The removal motion itself activates the retraction sequence through the removal trigger mechanism, eliminating the need for separate sensors or timing mechanisms while ensuring reliable activation.
Solution Approach 2:
The spring mechanism is pre-loaded during the injection phase and automatically releases when the removal trigger is activated. This preliminary preparation ensures that the retraction action occurs immediately and reliably when triggered, without requiring complex real-time control systems.
2Reliability
If safety margins are overestimated to ensure complete injection, then the injection sequence is effective, but medicament spillage occurs after needle withdrawal and dose accuracy is reduced
Solution Approach 1:
The device provides visual feedback through a dose indicator that shows the user when the injection is complete and when it is safe to remove the injector. This feedback mechanism allows the user to control the timing of removal to coincide with complete medicament delivery, preventing both incomplete injection and medicament spillage.
3Ease of operation
If a user actuated withdrawal mechanism is provided, then the user has control over needle withdrawal timing, but the risk of removing the injector before activation increases and the needle remains exposed longer
Solution Approach 1:
The user's natural removal action of the injector from the injection site automatically triggers the needle retraction mechanism. This eliminates the need for separate activation steps while ensuring the user maintains control over when withdrawal occurs, and the needle is retracted immediately upon removal to minimize exposure and contamination risk.
Data Source
AI summary
The present invention relates to an injection device, comprising a housing (10) including a container carrier (16) having a medicament container (18) and a needle (22) attached to the medicament container, a needle shield (12), means for initiating a penetration; penetration means for automatic penetration of needle, means for automatically injecting medicament, means for an automatically withdrawing the needle. The invention is characterized in an active triggering withdrawal mechanism capable of allowing the means for automatically withdrawing the needle to be triggered when the injection device starts to be removed from an injection site.