US 6,814,561 B2 · Apparatus and method for extrusion of thin-walled tubes

Abstract

The present invention provides an apparatus and method for manufacturing polymeric thin-walled tubular members, which are well-suited for use as vascular grafts. The apparatus of the present invention enables extrusion of a tubular member having an extremely thin wall thickness so as to facilitate passage through tortuous vascular passageways. The apparatus achieves uniform wall thickness in a tubular member by establishing and maintaining axial alignment of a ram having a concentrically disposed guide rod therein with a die supported in concentric relation to the guide rod.

Claims54

Dependent claims

An apparatus for extrusion of at least one thin-walled tubular member from a pre-form of polymeric material, said apparatus comprising:

an extrudate die having an orifice formed therethrough;
a barrel having a bore in communication with said orifice;
a piston slideably disposed in said bore;
a ram mounted to said piston;
and
a guide rod extending through said bore, said guide rod being constrained so as to maintain a relatively constant annular gap between said barrel and said guide rod, wherein said guide rod is hollow and coupled to a source of a pressurized stable medium.

3 more elements

Dependencies are inferred from the claim text.

Facts

Application

10/012,825Filed 30 Oct 2001

Published

US 2003/0082323 A11 May 2003

Granted

9 Nov 2004

Term ends

Not estimatedThe source records don’t support an estimate.

Classification16 codes

B29C 48/475
Means for plasticising or homogenising the moulding material or forcing it through the nozzle or die: using pistons, accumulators or press rams
B29C 45/531
Using injection ram or piston: drive means therefor
B29C 48/0012
Combinations of extrusion moulding with other shaping operations: combined with shaping by internal pressure generated in the material, e.g. foaming
B29C 48/022
Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor:…

Apparatus and method for extrusion of thin-walled tubes

Life of this patent

Apparatus and method for extrusion of thin-walled tubes

Life of this patent

Abstract

Claims54