Methods and apparatuses for forming fibrous tubes
Inventors
Engelmayr, JR., George C. • Niklason, Laura E. • DAHL, Shannon L. • STRADER, Justin T. • Zhang, Jinlin • IRWIN, Stuart
Assignees
Publication Number
US-10363124-B2
Publication Date
2019-07-30
Expiration Date
2035-09-18
Interested in licensing this patent?
MTEC can help explore whether this patent might be available for licensing for your application.
Abstract
Embodiments of the present disclosure are directed to apparatuses and methods for fabricating tubular structures from a combination of fibrous materials for use in, for example, tissue engineering scaffold applications. These materials may also be useful in other biological or non-biological applications in which such tubular fibrous structures may be applicable, examples including conventional medical devices, filters, fiber optics, cable wraps, geotextiles, batteries, fuel cells, armor, and other diverse applications.
Core Innovation
The invention relates to methods and apparatuses for fabricating tubular structures from fibrous materials, particularly for tissue engineering scaffold applications. The disclosed methods involve providing a strip of fibrous scaffolding material with defined dimensions and aligning its lengthwise edges immediately adjacent to each other to form a tubular structure. This structure is then tangentially punctured along the boundary between the edges using at least one needle to intertwine fibers and create a seam, forming a stable tubular scaffold.
The apparatus embodiments include a mandrel configured to receive the strip wound around its circumference, with first and second structures having recesses that receive portions of this mandrel and strip. A channel in the second structure allows needles to tangentially puncture the formed tubular structure along the seam line, intertwining fibers from adjacent edges. Mechanized actuators can insert, retract, and move the needles longitudinally to automate this process. Additional features include a third partial-cylindrical structure to align edges before puncturing.
The problem addressed arises from prior manual methods of forming nonwoven fibrous tubes, which are time-consuming, inconsistent, and yield variable seam uniformity and mechanical properties. Manual entanglement using single barbed needles can require skillful operation and long processing times to produce uniform seams. The invention seeks to provide automated and reproducible methods and apparatuses for efficiently forming uniform fibrous tubular scaffolds with controlled seam properties, improving scalability and reliability for tissue engineering and other applications.
Claims Coverage
The patent discloses nine claims with one independent claim focusing on a system for forming tubular scaffolds using a mandrel and needle puncturing technique. The subsequent claims depend on and add specific features to this core system. The main inventive features from the claims are as follows.
System for forming tubular scaffolds using a mandrel and needle puncturing
A system comprising a mandrel configured to receive a strip of scaffolding material wound around it, first and second structures with recesses to receive portions of the mandrel and strip, a channel along the second structure adjacent to the seam boundary, and at least one needle arranged adjacent to the channel configured to tangentially puncture the tubular structure along the lengthwise boundary to intertwine fibers and form a seam.
Electromechanical linear actuator for needle manipulation
An electromechanical linear actuator configured to insert and retract the needle(s) repeatedly through the channel and move the needle(s) longitudinally along the channel to enable automated puncturing and seam formation.
Needle positioning prior to puncturing
The electromechanical linear actuator is configured to position the needle(s) at a determined distance from the tubular structure before tangential puncturing to ensure proper alignment and operation.
Use of multiple needles
The system may include a plurality of needles arranged to puncture the tubular structure, enhancing the efficiency and uniformity of the seam formation.
Needles with barbed triangular blades arranged in a linear array
The plurality of needles comprises needles with barbed triangular blades arranged in a linear array, with the faces of the blades oriented substantially identically to optimize fiber entanglement during puncture.
Partial-cylindrical third structure for edge alignment
A quarter-cylindrical third structure configured to comb over one lengthwise edge of the strip to align the first and second lengthwise edges immediately adjacent to each other, facilitating formation of the tubular structure.
Needles arranged in a predetermined pattern
The plurality of needles are arranged in a predetermined pattern to achieve consistent puncture locations and seam formation.
Multiple advancement and retraction cycles of needles
The needles are configured for repeated advancing and retracting cycles to improve fiber entanglement along the seam.
Means for repetitive needle tip advancement and retraction
The system further comprises means configured for repetitive advancement and retraction of at least the tips of the needles, supporting mechanized puncturing operations.
The claims collectively cover a mechanized system for producing tubular fibrous scaffolds by winding material around a mandrel and forming a seam through tangential needle puncturing with mechanized needle actuation, edge alignment structures, and needle arrays designed for effective fiber entanglement. These features improve automation, consistency, and efficiency in scaffold tube fabrication.
Stated Advantages
Automating the formation of scaffolding tubes reduces time consumption compared to manual methods, potentially requiring fewer motions to entangle the materials.
The methods and apparatuses improve uniformity of seam lines and scaffold tensile mechanical properties by controlling seam density and needle actions.
Automated and mechanized processes reduce variability associated with technician skill and training inherent in manual entanglement techniques.
The seam formed is distinguishable and consistently aligned, facilitating reliable orientation when loading the scaffold into bioreactors or for further processing.
Documented Applications
Tissue engineering scaffolds, especially for vascular and soft tissue structures requiring tubular shapes for cellular attachment, proliferation, and extracellular matrix synthesis.
Medical devices including those that can incorporate degradable and non-degradable fibrous materials formed into tubes.
Biological and non-biological applications such as filters, fiber optics, cable wraps, geotextiles, batteries, fuel cells, and armor where tubular fibrous structures are applicable.
Interested in licensing this patent?