Expandable Blood Pump Rotor with Axial Control Body
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing blood pumps face challenges in efficiently compressing and expanding their rotors and housings for minimally invasive procedures, requiring high material demands and significant force efforts, which can lead to wear and instability.
Innovation Solution
A blood pump design featuring a radially compressible and expandable rotor with a hub and impeller blades, utilizing a control body that exerts axial forces to compress or expand the housing without requiring movement from the rotor or hub, and incorporating selectively modified materials with varying mechanical properties for enhanced stability and deformability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Length of moving object
If the rotor is made radially compressible for transport, then the pump can be introduced via blood vessels, but the material properties required become very high and compression forces increase wear
Solution Approach 1:
The patent applies composite materials consisting of a base material and integrated reinforcing struts. The struts are arranged to provide mechanical strength in specific directions, allowing the rotor to withstand high compression forces during transport while maintaining the necessary radial compressibility for vascular introduction. This composite structure resolves the contradiction by distributing stress across different material components.
Solution Approach 2:
The patent implements local quality by varying the strut distribution and material properties in different regions of the rotor. The struts are strategically positioned to provide enhanced strength where compression forces are highest, while other regions maintain greater flexibility for compression. This localized optimization allows the rotor to achieve the required strength-to-compressibility ratio without uniformly high material demands throughout the entire structure.
2Length of moving object
If the impeller blades are folded onto the hub for compression, then the rotor can be compressed, but the impeller blades must be deformed greatly in locally bounded regions
Solution Approach 1:
The patent segments the impeller blade structure by integrating separate struts within the blade body. These struts act as internal support elements that divide the blade into multiple structural zones. During compression, the struts guide the deformation process, distributing the folding action across multiple localized regions rather than concentrating extreme deformation in single areas. This segmentation reduces peak deformation demands on any one region.
Solution Approach 2:
The patent incorporates struts that are pre-positioned within the impeller blade structure before compression occurs. These struts are designed to engage and guide the folding process as compression begins, preventing uncontrolled deformation. The preliminary placement of these structural elements ensures that the blade folds in a predictable, distributed manner, reducing extreme local deformation requirements.
3Duration of action of moving object
If memory alloys are used for support struts, then the rotor can change shape with temperature, but the construction becomes more complex
Solution Approach 1:
The patent utilizes temperature-dependent parameter changes in smart materials for the support struts. The struts are made from materials that automatically change their mechanical properties (such as stiffness or shape) in response to temperature variations. This allows the rotor to undergo controlled shape changes during compression and expansion without requiring complex external actuation mechanisms. The parameter change approach simplifies the overall system by using intrinsic material properties rather than additional control systems.
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 allows for efficient, low-force compression and expansion of the pump components, maintaining stability in the expanded state and enabling reversible compressibility, thus optimizing the blood pump's performance and reducing wear.
Implementation Method 1
the housing (19, 19') is/are compressible or expandable in the radial direction by a axial stretching or axial compression
Implementation Method 2
the rotor (43, 27) and/or the housing (19, 19') is/are radially compressible and expandable
Implementation Method 3
The erection of the impeller blades can take place, for example, by the rotation of the rotor in operation in that the impeller blades are erected by the arising fluid counter-pressure on the rotation
Implementation Method 4
Constructions are, for example, known having support struts made from memory alloys which change their shape in dependence on the environmental temperature
Implementation Method 5
at least a part of the rotor (43, 27), in particular an impeller blade, and/or at least a part of the housing comprise(s) a material which be softened or hardened by radiation and if selected regions (32, 33, 34, 36, 37, 38, 39, 40) are stiffened by selective radiation hardening
Data Source
AI summary
Disclosed is a blood pump for the invasive application within a body of a patient comprising a rotor which is drivable about an axis of rotation and is radially compressible or expandable and which has a hub and at least one impeller blade fastened thereto, as well as comprising a housing which is compressible or expandable in the radial direction by an axial stretching or axial compression. Both the rotor and the housing are made expandable and compressible in as simple a manner as possible in that a control body is provided which passes through the hub in the longitudinal direction, which is freely axially displaceable relative to the hub and which is coupled to the housing on the distal side of the rotor such that it exerts pulling and/or compression forces on the housing by a movement in the longitudinal direction with respect to the housing.