Drug Delivery Needle Shroud–Collar Feedback for Dose Completion
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing injection devices, both manual and autoinjectors, face challenges such as the need for manual force application, potential premature dose interruption, difficulty in aligning and keeping the device still during injection, and dexterity requirements that may be beyond the capabilities of certain users, particularly the elderly or children, and the desire to ensure full dose administration for medicament effectiveness.
Innovation Solution
A drug delivery device with a feedback mechanism comprising a collar and needle shroud that decouples upon full dose delivery, providing audible and tactile feedback, and a plunger release mechanism to ensure complete dose administration, featuring a control spring and snap-fit joints for secure needle shroud locking.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If a conventional manual injection device is used, then the device structure is simple, but manual force is required and dexterity is needed for alignment and operation
Solution Approach 1:
The injection device is divided into distinct functional modules: a trigger mechanism for force application, a plunger assembly for medicament delivery, a needle shroud for safety, and a feedback mechanism for dose monitoring. Each module operates independently but coordinates through defined interfaces, reducing the dexterity required for operation while maintaining structural simplicity.
Solution Approach 2:
The device incorporates automatic plunger release upon trigger activation, automated needle shielding after injection, and self-indicating dose delivery status through feedback mechanisms. These self-service features eliminate the need for manual intervention during critical injection phases, making the device easier to operate for users with limited dexterity.
2Reliability
If a conventional autoinjector is used, then activation is automated, but feedback on dose delivery status is limited
Solution Approach 1:
The device incorporates multiple feedback mechanisms: visual indicators showing dose remaining, tactile feedback through spring resistance changes, and audible clicks indicating dose completion. The needle shroud's movement relative to the collar provides mechanical feedback on plunger position and dose delivery status, ensuring users have comprehensive information about injection progress and completion.
3Productivity
If the plunger is continuously pressed during injection, then force is applied to deliver medicament, but premature release stops the injection and may not deliver intended dose
Solution Approach 1:
The trigger mechanism is pre-loaded with spring force ready to apply to the plunger upon activation. The plunger is pre-positioned against the medicament, and the needle is pre-extended into position. When the trigger is pulled, all these actions occur automatically and simultaneously, ensuring complete dose delivery without requiring continuous manual pressure or monitoring.
4Stability of the object's composition
If the needle shroud is locked to the collar, then the structure is stable, but the feedback mechanism cannot activate when full dose is spent
Solution Approach 1:
The needle shroud-c collar connection transitions from a static locked state to a dynamic movable state through snap-fit joints. During normal operation, the snap-fits maintain stable coupling. When the plunger reaches its distal position indicating dose completion, the snap-fit joints automatically release, allowing the needle shroud to move independently and activate the feedback mechanism, thus adapting the structure's stability based on operational needs.
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
Ensures complete medicament delivery with user-friendly operation, reducing the risk of premature dose interruption and ensuring full dose administration, while being suitable for various medicament viscosities and user types, with enhanced safety and reliability.
Implementation Method 1
a control spring biasing the collar in a distal direction
Implementation Method 2
The collar comprises one or more resilient first snap-fit joints adapted to couple to the needle shroud in a ramp engagement in the first state
Data Source
AI summary
A drug delivery device includes a case adapted to hold a medicament container, a plunger disposed within the case and slidable from a proximal position into a distal position for delivering a medicament from the medicament container, at least one feedback mechanism that is in operative connection with the plunger. The feedback mechanism comprises a collar, a control spring biasing the collar in a distal direction, a needle shroud, operatively axially abutting the collar in a first coupled state and prevented from axially decoupling the collar by the plunger in its proximal position The plunger, when approaching the distal position during movement from the proximal position towards the distal position, is adapted to allow axial decoupling of the needle shroud from the collar, allowing for a limited axial movement of the collar relative to the needle shroud until the collar axially abuts the needle shroud in a second coupled state.