Proximity-Sensed Injector Plunger Lock for Detachment Control

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing drug delivery devices continue to deliver drug even after detachment from the patient, leading to incomplete dosing, unawareness of incomplete delivery, and inability to determine the amount delivered.

Innovation Solution

A drug delivery device equipped with a proximity sensor that moves relative to the housing, transitioning between sensor states to limit plunger movement and prevent further drug delivery when detached from the patient, and optionally indicating the amount delivered.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If automated needle insertion and drug delivery is implemented to simplify the process for patients with physiological or psychological impediments, then ease of operation is improved, but the risk of unintended continuous delivery after detachment increases

Engineering Contradiction:

Improveease of operationVSAvoidreliability

Core Design Contradiction:

Ease of operationVSReliability

Solution Approach 1:

The proximity sensor is activated in advance to detect whether the device is attached to the patient before drug delivery begins. This preliminary detection allows the system to prepare the lock mechanism to prevent unintended continuous delivery after detachment, resolving the contradiction by enabling automated operation while maintaining reliability through pre-emptive safety monitoring.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The proximity sensor provides continuous feedback to the lock mechanism about the device's attachment status. When detachment is detected, the feedback signal triggers the lock to prevent further plunger movement, ensuring that automated delivery stops reliably. This feedback loop resolves the contradiction by maintaining both ease of automated operation and reliability of delivery control.

Inventive Principle:

Principle #23Feedback

2Quantity of substance

If the device continues to deliver drug after detachment to ensure complete dosing, then quantity of substance delivered is improved, but the patient receives incomplete dose when detachment occurs, worsening the outcome

Engineering Contradiction:

Improvequantity of substanceVSAvoidreliability

Core Design Contradiction:

Quantity of substanceVSReliability

Solution Approach 1:

The proximity sensor detects attachment status in advance before detachment occurs. This preliminary detection allows the system to stop delivery proactively when detachment is detected, preventing the harmful outcome of incomplete dosing while avoiding the harmful outcome of unintended continuous delivery after detachment.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The proximity sensor provides real-time feedback about attachment status to the lock mechanism. When detachment is detected, the feedback signal immediately triggers the lock to prevent further plunger movement, ensuring that the full intended dose is delivered only when properly attached. This resolves the contradiction by ensuring complete dosing is achieved reliably without unintended continuous delivery.

Inventive Principle:

Principle #23Feedback

3Reliability

If a proximity sensor and lock mechanism are added to prevent unintended delivery after detachment, then reliability is improved, but device complexity increases

Engineering Contradiction:

ImprovereliabilityVSAvoiddevice complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The proximity sensor and lock mechanism are integrated into the existing device architecture, sharing common components and control circuits. This merging approach implements the safety functionality to prevent unintended delivery after detachment while minimizing the increase in device complexity by consolidating elements rather than adding entirely separate systems.

Inventive Principle:

Principle #5Merging (Combining)

4Difficulty of detecting and measuring

If the proximity sensor remains extended to detect detachment, then detection capability is improved, but the sensor is exposed to external contaminants, worsening reliability

Engineering Contradiction:

Improvedetection capabilityVSAvoidcontaminant exposure

Core Design Contradiction:

Difficulty of detecting and measuringVSObject-affected harmful factors

Solution Approach 1:

The proximity sensor is designed to dynamically change its position between extended and retracted states based on operational requirements. When detection is needed, the sensor extends to improve detection capability. When not in use or during critical delivery phases, the sensor retracts to minimize exposure to external contaminants. This dynamic positioning resolves the contradiction by balancing detection capability with protection from harmful factors.

Inventive Principle:

Principle #15Dynamics

Data Source

PatentUS12415039B2Drug delivery device with proximity sensor

Publication Date: 2025.09.16 AMGEN INC

AI summary

A drug delivery device, in the form of an injector, may include one of a number of systems for limiting the delivery of a medical fluid or drug product in case of movement of (e.g., removal of) the injector relative to the patient as determined by a proximity sensor. The drug delivery system may in the alternative or in addition include systems for indicating the amount of medical fluid or drug product delivered (or not delivered) in case of movement of (e.g., removal of) the injector relative to the patient as determined by the proximity sensor. The injector may be, for example, an on-body injector or an hand-held autoinjector.