Expandable Impeller Support for Small-Diameter Fluid Pumps
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing fluid pumps with rotating impeller blades face challenges in achieving a good pumping capacity while maintaining a small diameter, particularly when introduced through blood vessels, due to the mechanical constraints and stiffness requirements of the impeller blades.
Innovation Solution
The design incorporates an impeller blade that is rotatable about an axis of rotation and supported by a support device, which changes between compressed and expanded states, with the support region offset radially outward, allowing the impeller blades to be weaker and more flexible, and is connected to the impeller blades through a support device that can be made of materials like nitinol or a shape memory alloy to actively change shape, eliminating the need for a neck and enabling efficient fluid conveyance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If impeller blades are supported in the region of the axis of rotation, then the support device can be simpler, but the impeller blades require high stiffness and strength to convey fluid effectively
Solution Approach 1:
The support region is inverted from the conventional location at the axis of rotation to an offset position radially outward. This inversion allows the impeller blades to be supported where they naturally have higher relative speed and mechanical load, enabling weaker, more flexible blade design while maintaining effective fluid conveyance.
Solution Approach 2:
The support device is localized to a specific offset region rather than supporting at the axis. This local support positioning allows different regions of the impeller blade to have different properties - the supported region can be weaker while maintaining sufficient strength where needed for fluid conveyance.
2Volume of moving object
If impeller blades are made weaker and more flexible, then the pump diameter can be reduced, but the pumping capacity may be compromised
Solution Approach 1:
The support region parameter is changed from axial (at the axis of rotation) to radial offset position. This parameter change allows the impeller blades to operate with lower stiffness requirements while maintaining adequate pumping capacity, enabling smaller pump diameter.
Solution Approach 2:
The impeller blades are designed to be dynamically flexible rather than statically rigid. The offset support region allows the blades to flex and deform during rotation, optimizing their fluid conveyance capability while maintaining a compact diameter.
3Stability of the object's composition
If a neck is used to connect impeller blades to the rotor axis, then the structural integrity is improved, but the pump diameter increases
Solution Approach 1:
The neck component is extracted and removed from the design. Instead of using a neck to connect impeller blades to the rotor axis, the support device is positioned radially outward, eliminating the need for the neck structure and reducing the pump diameter while maintaining structural integrity through alternative support mechanisms.
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
This design achieves a high pumping capacity with a small pump diameter, allowing for efficient fluid conveyance and simplified manufacturing, while reducing mechanical demands on the support device and impeller blades, and enabling compactness for use in difficult-to-access areas like the human heart.
Implementation Method 1
the support device that can be made of materials like nitinol or a shape memory alloy to actively change shape
Data Source
AI summary
The invention relates to a fluid pump having at least one impeller blade (1, 1′, 1″) which is rotatable about an axis of rotation (3) and conveys a fluid in operation and comprising a support device (4, 6, 7, 8, 9, 10, 12, 12′, 13, 13′, 14, 14′, 15, 17) which supports the at least one impeller blade (1, 1′, 1″) in at least one support region, wherein the support device is changeable between a first state in which the rotor is radially compressed and a second state in which the rotor is radially expanded; and wherein at least one impeller blade extends at least partly radially inwardly with respect to the axis of rotation (3) from the support region/support regions in the radially expanded state of the rotor.