Injection Device Dose Tracker Mechanism
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing injection devices for medicaments lack mechanisms to prevent unintended overdosing or underdosing, particularly for patients with impaired vision or dexterity, and do not provide easy and intuitive dose setting and dispensing processes.
Innovation Solution
The injection device features a longitudinally displaceable dose tracker that is automatically set and dispensed using a spring mechanism and interlock system, providing clear and intuitive feedback to the user, and allowing for the preselection of multiple dose sizes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a traditional syringe-like injection device is used, then the device structure is simple, but the patient cannot easily control the dose size and is prone to overdosing or underdosing
Solution Approach 1:
The injection device is divided into functionally independent modules: a dose setting mechanism with a dose tracker, a drive mechanism with piston rod, and a cartridge holder. This segmentation allows each module to perform its specific function independently, improving dose control accuracy while maintaining overall structural clarity and manageability.
Solution Approach 2:
The dose tracker provides visual feedback to the patient about the current dose setting and dispensing progress. The tracker moves along with the piston rod, giving the patient real-time information about the injection process, which helps them understand and control the dose administration better.
2Ease of operation
If the injection device is designed for easy operation by patients with impaired vision or dexterity, then the ease of operation improves, but the device complexity increases due to additional feedback mechanisms
Solution Approach 1:
The dose tracker serves as a simple yet effective feedback mechanism that moves visibly with the piston rod. This mechanical feedback is intuitively understandable for patients with impaired vision or dexterity, as it provides tactile and visual confirmation of the dosing process without requiring complex electronic displays or controls.
Solution Approach 2:
The injection device is designed to be self-explanatory through its mechanical feedback mechanisms. The dose tracker automatically indicates the dosing status without requiring the patient to read instructions or interpret complex displays, making the device self-service friendly for patients with limited capabilities.
3Reliability
If a mechanism is added to prevent unintended overdosing or underdosing, then the patient safety improves, but the device complexity increases
Solution Approach 1:
The safety mechanism is segmented into distinct functional elements: the dose tracker that monitors dispensing progress, the piston rod that controls medicament delivery, and the cartridge holder that contains the dose. This segmentation allows the safety function to be distributed across multiple components rather than requiring a single complex safety system.
Solution Approach 2:
The dose tracker provides continuous feedback on the dispensing process, allowing the patient or caregiver to monitor and control the injection. This feedback mechanism helps prevent unintended overdosing or underdosing by making the dosing progress transparent and controllable, while adding only minimal complexity to the overall device.
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 device enhances patient safety by preventing overdosing or underdosing, simplifies the dose setting and dispensing process, and is user-friendly even for patients with impaired vision or dexterity.
Implementation Method 1
The injection device further comprises a spring to urge the dose tracker in the proximal direction relative to the housing
Data Source
AI summary
An injection device includes an elongated housing extending along a longitudinal axis, a piston rod to operably engage with a piston of a cartridge filled with the medicament, a dose tracker selectively operably engageable with the piston rod, wherein the dose tracker is longitudinally displaceable relative to the housing from an initial position in a proximal direction towards at least a first activation position for setting of the dose and wherein the dose tracker is longitudinally displaceable relative to the housing in a distal direction from the at least first activation position towards the initial position for dispensing of the dose, a spring to urge the dose tracker in the proximal direction relative to the housing, an interlock to lock the dose tracker in the initial position relative to the housing, and a release member to release the interlock.