Autoinjector Rotating Locking Collar and Stepped Thread Feedback
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current autoinjectors face challenges in delivering viscous protein therapeutics due to high viscosity and force requirements, and many patients struggle to activate the devices correctly or receive feedback on medication delivery completion, leading to incomplete doses.
Innovation Solution
The autoinjector design features a rotating locking collar and nut mechanism with a sleeve spring for easier activation and needle insertion, along with an audible/tactile end-of-dose indicator through a stepped thread in the nut sector, ensuring full dose delivery and safe needle protection.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If a button activation mechanism is used, then the device can be activated, but patients may lack the ability to correctly place and press the button, leading to activation difficulties
Solution Approach 1:
The autoinjector is designed to activate automatically when placed on a flat surface, eliminating the need for patient manipulation of buttons or switches. The device self-activates through the mechanical action of placing it on a surface, which triggers the release mechanism internally.
Solution Approach 2:
The manual button-pressing mechanical system is replaced with a surface-activation mechanical system where the act of placing the device on a flat surface initiates the activation sequence through pre-configured mechanical linkages.
2Productivity
If high force is applied to push viscous medication through the needle, then the medication can be delivered, but the needle insertion becomes painful and difficult
Solution Approach 1:
The needle is pre-loaded in a retracted position within the device housing. The activation mechanism first drives the needle forward to the injection site, establishing the injection pathway before the medication delivery phase begins, separating the insertion force requirement from the medication push force requirement.
Solution Approach 2:
The device employs a dynamic force delivery system where the plunger applies medication force progressively throughout the injection stroke, adjusting the force profile to maintain comfortable levels while ensuring complete delivery of viscous medication over time.
3Reliability
If no feedback mechanism is provided, then the device structure remains simple, but patients cannot know when medication delivery is complete, leading to early removal
Solution Approach 1:
The device incorporates an audible feedback mechanism in the form of a click sound that occurs at the end of the injection stroke. This acoustic signal provides clear indication to the patient that medication delivery is complete, ensuring the device remains in place for the full duration required.
4Reliability
If the activation mechanism requires multiple components, then the release function can be achieved, but the device becomes more complex and harder to manufacture
Solution Approach 1:
The activation mechanism integrates multiple functions into a unified structure where the activation button, release lever, and spring-loaded plunger are combined into a single coordinated assembly. The button simultaneously initiates the release sequence and the spring mechanism provides both the activation force and the reset function.
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 solution enables reliable, user-friendly delivery of viscous medications with clear feedback on dose completion, enhancing patient compliance and ensuring complete medication administration while preventing needle exposure.
Implementation Method 1
wherein the activation sleeve is extended by a sleeve spring when the device is removed from a patient's skin surface after delivery of medication is complete
Implementation Method 2
pressing an activation sleeve that is located at a proximal end of an injector; wherein the activation sleeve rotates a locking collar using a camming action
Implementation Method 3
wherein the plunger screw pins are forced down a helical thread by the drive spring thereby inserting the needle and delivering medicant to a patient
Data Source
AI summary
Autoinjectors and methods of injection are described that feature release mechanisms and/or end-of-dose sound which can operate in conjunction with a powered plunger to efficiently inject a controlled dose from a syringe.