Flexible Actuator Material for Osmotic Fluid Metering
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Osmotic delivery systems face delays due to air pockets or voids that compress during start-up, leading to inaccurate and delayed fluid delivery, and struggle with delivering viscous pharmaceutical agents due to insufficient osmotic pressure.
Innovation Solution
A flexible actuator material is used that can be compressed during assembly to create a preloaded pressure condition, eliminating dead airspace issues and generating pressures exceeding 50 psi through protonated molecular repulsive forces upon hydration, allowing for immediate fluid delivery and effective dispensing of viscous agents.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of time
If a flexible actuator material is compressed during assembly to create preloaded pressure, then fluid delivery speed and accuracy are improved, but device complexity increases
Solution Approach 1:
The actuator material is compressed during assembly to pre-load the spring element, storing elastic potential energy before operation. This preliminary compression eliminates startup delays by ensuring the actuator is already pressurized and ready to deliver fluid immediately when activated, rather than requiring time to build pressure from a relaxed state.
2Stress or pressure
If osmotic pressure is used to deliver fluids, then device simplicity is maintained, but pressure generation is insufficient for viscous pharmaceutical agents
Solution Approach 1:
The invention changes the physical parameter of the actuator material from a passive osmotic membrane to an active flexible material with spring-like properties. This material can be compressed to store elastic energy and then expand to generate high pressure, transforming the pressure generation mechanism from passive osmotic pressure to active elastic recovery, enabling delivery of viscous agents.
Solution Approach 2:
The actuator system uses a composite structure combining the flexible actuator material with the osmotic pump core. The flexible material acts as both the driving mechanism and the structural element, integrating multiple functions (pressure generation, fluid containment, and actuation) into a unified composite system that overcomes the limitations of pure osmotic pressure.
3Ease of operation
If the device is made more flexible for patient comfort, then ease of operation is improved, but pressure generation capability deteriorates
Solution Approach 1:
The device employs local quality differentiation where the actuator material exhibits flexible, compliant properties in its relaxed state for patient comfort, but can be locally compressed during assembly to store elastic energy. When activated, the localized elastic recovery generates high pressure precisely where needed for fluid delivery, while the overall device structure remains flexible and comfortable for the patient.
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 flexible actuator material ensures timely and accurate fluid delivery by relaxing to dispense fluids as soon as restrictions are released, and generates sufficient pressure to deliver most pharmaceutical agents, overcoming the limitations of osmotic pressure in osmotic delivery systems.
Implementation Method 1
osmotic delivery systems operate by absorbing fluid from the outside environment and releasing corresponding amounts of the beneficial agent
Implementation Method 2
generating pressures exceeding 50 psi through protonated molecular repulsive forces upon hydration
Data Source
AI summary
A device for metering fluids comprising a fluid chamber with one inlet or outlet port, at least one sidewall and a movable separator that is in contact with and separates the fluid in the chamber from the other components of the device, a porous actuator housing and wicking material, a flexible polymer actuator material in contact with the porous actuator housing and the moveable separator, an actuator hydrating solution reservoir with at least one sidewall, an inlet port, and in fluid contact with porous actuator housing, a fluid gate located at some point between actuator hydrating solution reservoir and the polymer actuator, effectively keeping actuator dry, and an external shell to hold all components so that the polymer actuator can only move in a direction and apply pressure to the separator in contact with the fluid in the fluid chamber, thereby dispensing fluid from fluid chamber.