Vacuum-Coupled Membrane Pump for Disposable Fluid Path
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Reusable medication delivery pumps face challenges such as high complexity, high costs, low reliability, and performance issues due to undesirable compliance, which affects flow uniformity and can lead to air entrainment, reducing net pumping volume.
Innovation Solution
A fluid pump design featuring a drive unit and a disposable driven unit with vacuum-coupled membranes that move to change the volume of a fluid chamber, allowing for precise control of fluid flow and preventing backflow, incorporating features like air traps and pressure sensors to enhance performance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the pump is designed as a single integral unit, then sterilization is difficult and compliance is high, but the structure is simple and cost is low
Solution Approach 1:
The pump is divided into two separate units: a reusable drive unit containing the driving membrane and motor, and a disposable driven unit containing the driven membrane and fluid path. This segmentation allows the fluid-contacting driven unit to be easily sterilized or discarded, while the drive unit can be reused, resolving the contradiction between sterilization capability and structural simplicity.
2Reliability
If the pump uses reusable components with fluid path separation, then sterilization is improved, but device complexity and manufacturing cost increase
Solution Approach 1:
The driven unit is designed as a disposable component that is inexpensive to manufacture and can be discarded after use. This eliminates the need for complex sterilization processes and reduces manufacturing costs for the overall system, as the disposable unit absorbs the fluid-contacting functions while the expensive drive unit remains reusable.
3Adaptability or versatility
If the pump uses elastic tubing for fluid path, then compliance is high, but flow uniformity deteriorates under varying pressure
Solution Approach 1:
The pump uses a flexible driven membrane made of elastic material (such as silicone rubber or fluoropolymer) that can expand and contract to accommodate pressure variations. This flexible membrane maintains high compliance while ensuring uniform flow delivery, as its elastic properties allow it to adapt to changing pressure conditions without compromising flow consistency.
4Reliability
If dual chamber pumping regions are used, then flow smoothing is improved, but air entrapment likelihood increases and compliance worsens
Solution Approach 1:
The pump uses a single pumping chamber with a driven membrane instead of dual chambers. This segmented design eliminates the interfaces between chambers where air can become trapped, while still achieving flow smoothing through the controlled expansion and contraction of the driven membrane. The single-chamber design reduces air entrapment risk while maintaining compliance.
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 design achieves improved flow control, reduced complexity, and cost-effectiveness by allowing the disposable portion to be easily replaced or sterilized, while maintaining high reliability and preventing air entrainment, thus ensuring consistent and efficient medication delivery.
Implementation Method 1
The driving and driven membranes are vacuum coupled, such as by applying a vacuum source to a vacuum path or line extending to the interface of the membranes.
Implementation Method 2
The drive device includes a piston or other member for changing the volume of the chamber
Data Source
Figure 1~2
Figure 3~4
Figure 5
AI summary
A pump having a disposable fluid contacting portion which defines a fluid inlet and outlet and a fluid path there between is presented. The pump includes a drive portion configured to engage the disposable portion to cause fluid to be moved from the fluid inlet to the fluid outlet. The disposable portion is configured to selectively coupled to the drive portion. The disposable portion includes a driven membrane which forms a portion of the fluid path, and the drive portion includes a drive membrane. The two membranes are vacuum coupled to each other, whereby movement of the drive membrane causes the driven membrane to move, causing fluid to be pumped through the disposable portion. The pump has particular utility in the medical field for moving fluid from a source to a patient. The pump may include features such as an air-trap, bubble detection, fluid flow controls, and pressure detection.