Method and apparatus for winding hollow filaments

A machine for preparing bundles of hollow, semi-permeable filaments for use in a hollow fiber dialyzer, said machine comprising:

• supply spool mounting means providing a continuous supply of said hollow, semi-permeable filaments;
• a rotatably mounted take-up reel receiving and carrying a filament winding formed of filament from said supply spool mounting means, and filament guide means cooperatively associated with said take-up reel for controlling the lateral position of said filament on the take-up reel as said reel rotates, to prevent close packing of the filament winding, said take-up reel including a plurality of filament support assemblies on said take-up reel to receive and hold said filaments being wound on the reel, and to shape said filament winding into the general form of a polygon with filament support assemblies positioned at the corners thereof, the take-up reel having a diameter that greatly exceeds its width, including means for oscillating said guide means between a first lateral position and a second lateral position, whereby said filaments in the filament winding generally defines a small angle to the axis thereof, the sides of said filament winding being enclosed with split cases, each of which include upper and lower semi-cylindrical members, said upper and lower semi-cylindrical members being joined together into cylindrical members, enclosing said sides of the filament winding to facilitate the orderly maintenance of bundles of filaments which are formed by cutting said polygonally-shaped filament winding.

A method for preparing a hollow, substantially continuous, semi-permeable filament bundle for use in a hollow fiber dialyzer, which dialyzer includes a plurality of substantially-equal-length, open-ended fibers formed from said continuous filaments, comprising the steps of:

• providing at least one spool of said filament;
• unwinding said filament from said spool;
• winding said filament onto a take-up reel having a plurality of spaced filament support means so that each filament forms a plurality of elongated sections, each having a multiplicity of windings, and causing each filament being wound on the take-up reel to oscillate from side-to-side across the entire width of the elongated sections, to prevent close packing of the filament winding, to form a filament winding into the general form of a polygon with filament support assemblies positioned at the corners thereof, said filament winding defining a diameter that greatly exceeds its width;
• thereafter enclosing said elongated sections with split cases, each of which include upper and lower semi-cylindrical members, said upper and lower semi-cylindrical members being joined together into cylindrical members enclosing said sides of the filament winding to facilitate the orderly maintenance of said bundles of filaments which are formed by cutting said filament winding, and thereafter cutting said filament winding adjacent the ends of said split cases to form a plurality of open-ended filament bundles positioned within said split cases.