Magnetic Sensor Dose Measurement in Medication Delivery

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Medication delivery devices face challenges in accurately measuring and ensuring the proper delivery of medication doses due to mechanical system inaccuracies, requiring reliable sensing systems to assess relative movement between device members.

Innovation Solution

A sensing system with first and second sensor components secured to different members of the medication delivery device, detecting relative rotational movement to determine the amount of dose set and delivered, utilizing various sensing technologies such as tactile, optical, or magnetic measurements.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If mechanical sensing systems are used to measure relative movement between device members, then the system can assess dose set and delivered, but mechanical inaccuracies reduce measurement precision

Engineering Contradiction:
Improveaccuracy of dose measurementVSAvoidreliability of dose delivery
Core Design Contradiction:
Measurement precisionVSReliability

Solution Approach 1:

The patent replaces mechanical sensing systems with magnetic sensing systems. A magnet is attached to one device member and a magnetic sensor to another member, detecting relative movement through magnetic field changes rather than direct mechanical contact. This eliminates mechanical inaccuracies and wear while maintaining the ability to measure relative movement for dose assessment.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

2Measurement precision

If multiple sensor components are added to detect relative movement, then measurement accuracy improves, but device complexity increases

Engineering Contradiction:
Improveaccuracy of dose assessmentVSAvoidnumber of sensor components
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent introduces a magnet as an intermediary element that enables sensing without direct mechanical contact. The magnet attached to one member and the magnetic sensor on another member create a non-contact sensing mechanism, reducing the need for complex mechanical linkages and multiple contact-based sensors while maintaining measurement accuracy.

Inventive Principle:
Principle #24Intermediary (Mediator)

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

Provides accurate and reliable assessment of medication amounts set and delivered, is compact, and adaptable to various devices, reducing the risk of mechanical inaccuracies and ensuring patient safety.

Implementation Method 1

The sensor is a magnetic sensor and the target a magnet, or vice versa

Methodology Applied
Scientific EffectMagnetic field sensing: Magnetic Field

Data Source

PatentEP3432949B1Determination of a dose set and delivered in a medication delivery device
Publication Date: 2024.05.01 ELI LILLY & CO
  • EP3432949B1 patent drawingFigure 1~2
  • EP3432949B1 patent drawingFigure 3~4
  • EP3432949B1 patent drawingFigure 5~6

AI summary

Sensing systems are disclosed for determining the relative rotational movements of members of a medication delivery device which are proportional to the amount of a dose set and delivered by the medication delivery device. The sensing system comprises a first sensor component secured to a first member and a second sensor component secured to a second member. During dose setting, the second member is coupled to a third member which rotates relative to the first member in proportion to the dose set. During dose delivery, the second member is coupled to a fourth member which rotates relative to the first member in proportion to the dose delivered. The sensing system separately detects the relative rotational positions of the first and second sensor components during dose setting and dose delivery, and provides outputs used to determine the amounts of the set and delivered doses. The sensing system outputs this information to a controller which determines the amount of the dose set and delivered. Related medication delivery devices and methods are also disclosed.