Syringe Limiter Stop Mechanism for Partial Dose Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Patients face challenges in accurately dispensing partial doses of medication from prefilled syringes, leading to potential under or overdose issues due to difficulty in estimating markings on the syringe barrel during self-injection, especially for those with deteriorating manual dexterity.
Innovation Solution
A kit of limiters is provided, each with a housing and a stop configured to limit the plunger movement in a dispensing device to a predetermined distance, allowing for precise control of the medication volume dispensed, including configurations for easy handling and use with various forms of medication or substances.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If patients self-inject with prefilled syringes using graduated markings, then they can administer medication independently, but they risk inaccurate dosing leading to under or overdose
Solution Approach 1:
The limiter is pre-configured with a stop positioned at a specific distance from the plunger to define the desired injection distance. This preliminary setup eliminates the need for patients to estimate markings during self-injection, providing both independence and dosing accuracy simultaneously.
Solution Approach 2:
The limiter acts as an intermediary device between the patient and the syringe. It mediates the injection process by mechanically constraining plunger movement, thereby ensuring accurate dosing while maintaining patient independence in administering the medication.
2Measurement precision
If a limiter is added to control plunger movement, then dosing accuracy is improved, but device complexity increases
Solution Approach 1:
The limiter integrates multiple functions into a single structure: the housing receives the syringe barrel, the stop limits plunger movement, and the overall assembly provides dosing control. This merging approach improves dosing accuracy while minimizing the increase in device complexity.
Solution Approach 2:
The limiter is designed as a multi-functional device that can accommodate different syringe types and provide dosing control for various medication volumes. This universality allows a single limiter design to serve multiple purposes, reducing the need for multiple specialized components.
3Reliability
If the stop prevents further plunger movement, then medication reuse is prevented, but the device becomes harder to operate
Solution Approach 1:
The limiter divides the plunger movement into two distinct phases: the first phase allows movement up to the stop position for accurate dosing, and the second phase is blocked by the stop to prevent medication reuse. This segmentation provides both reliability and ease of operation by making the prevention mechanism intuitive and simple.
Data Source
Figure 1~2
Figure 3
Figure 4
AI summary
A limiter for a dispensing device is provided. The limiter includes a body (20) arranged to mount with at least a portion of a dispensing device (300), and a stop extending from the body. The stop (40) is configured to permit movement a plunger of the dispensing device a predetermined distance in a dispensing direction correlated to a desired volume of medium to be delivered from the dispensing device. The stop is configured to prevent further movement of the plunger in the dispensing direction, thereby limiting the amount of medium delivered from the dispensing device. The dispensing device may be a syringe.