Dialysis Cassette Integration for Precise Fluid Mixing and Balancing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing fluid pumping systems lack efficient integration and control of fluid mixing and balancing, particularly in applications requiring precise fluid volume equalization and continuous flow.
Innovation Solution
A cassette system integrating a mixing cassette, a middle cassette, and a balancing cassette, connected by fluid lines and pods, with membrane pumps and valves, enabling precise fluid control and equalization through reciprocating pressure displacement and metering pumps.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If separate pumping systems are used for fluid mixing and balancing, then system flexibility is maintained, but device complexity and space requirements increase
Solution Approach 1:
The patent combines multiple pumping systems (mixing pump and balancing pump) into a single integrated cassette unit with shared housing and coordinated control. The mixing cassette and balancing cassette are merged into one device that performs both fluid mixing and volume balancing functions simultaneously, reducing overall system complexity while maintaining functional versatility through internal segmentation of tasks.
Solution Approach 2:
The integrated cassette system is designed to perform multiple functions within a single device: fluid mixing, volume balancing, and coordinated pumping operations. The system can adapt to different fluid handling requirements by activating appropriate pumps and pathways, providing universal functionality for both mixing and balancing operations without requiring separate dedicated systems.
2Manufacturing precision
If traditional pumping systems are used, then structural simplicity is maintained, but manufacturing precision and fluid control accuracy decrease
Solution Approach 1:
The patent replaces traditional mechanical pumping mechanisms with membrane-based pumps that use pneumatic or electronic actuation. This substitution enables precise control of fluid volume and flow rate through controlled membrane displacement, achieving high manufacturing precision in fluid volume equalization while the modular cassette design manages the resulting device complexity.
Solution Approach 2:
The system achieves precise fluid volume equalization by dynamically changing operational parameters such as membrane pump stroke volume, pumping frequency, and pressure differential. These parameter adjustments allow accurate control of fluid transfer between mixing and balancing chambers, enabling high precision fluid handling despite the integrated cassette structure.
3Productivity
If manual fluid balancing is used, then device simplicity is maintained, but productivity and time efficiency decrease
Solution Approach 1:
The integrated cassette system performs fluid balancing automatically through coordinated operation of the mixing and balancing pumps. The system self-regulates fluid volume equalization between chambers without requiring manual intervention, achieving high productivity in fluid mixing and balancing operations while the automated control manages the complexity of the integrated pump system.
Solution Approach 2:
The system enables continuous fluid mixing and balancing operations through coordinated pump cycles that maintain constant fluid flow and volume equalization. The mixing pump and balancing pump operate in continuous coordinated cycles, eliminating idle time and maintaining productive fluid handling operations throughout the process, thereby increasing overall productivity despite the complex integrated design.
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 system achieves precise fluid mixing and balancing, ensuring equal volumes of fluids are pumped and directed to desired locations, enhancing fluid management efficiency and flexibility.
Implementation Method 1
at least one reciprocating pressure displacement membrane pump within the mixing cassette housing fluidly connected to the housing. The pressure pump pumps at least one fluid from the fluid inlet line to at least one of the fluid outlet line
Implementation Method 2
The balancing pod balances the flow of a first fluid and the flow of a second fluid such that the volume of the first fluid equals the volume of the second fluid
Implementation Method 3
The balancing pod includes a membrane wherein the membrane forms two balancing chambers
Data Source
Figure 1A
Figure 1B
Figure 2A
AI summary
A dialysis system comprising a fluid handling pump or valve cassette and a controller for controlling pumps or valves in said cassette; the cassette comprising a plurality of fluid flowpaths, and a plurality of pneumatically actuated diaphragm valves controlling fluid flow in said plurality of fluid flowpaths; a first group of one or more flowpaths configured to direct water from a source of water to a dialysate mixing circuit, the dialysate mixing circuit and water source being external to the cassette; a second group of flowpaths configured to direct dialysate solution from a source of dialysate solution to a dialysate tank, the dialysate solution source and dialysate tank being external to the cassette; a third group of flowpaths configured to direct dialysate solution from the dialysate tank to a dialysate balancing circuit of the dialysis system, the dialysate balancing circuit being external to the cassette; and a fourth group of flowpaths configured to direct dialysate solution from the dialysate solution source and from the dialysate balancing circuit to a drain, the drain being external to the cassette.