[54] METHOD FOR RAPID PROTOTYPING OF SOLID MODELS
[75] Inventors: John Samuel Batchelder, Somers,
N.Y.; Steven Scott Crump, Wayzata,
Minn.
[73] Assignee: Stratasys Inc., Eden Prairie, Minn.
[21] Appl. No.: 862,933
[22] Filed: May 29, 1997
[51] Int. C I. B29C 41/02
[52] U.S. CI 264/237; 264/308; 364/468.26
[58] Field of Search 264/237, 308,
264/401, 497; 364/468.26
[56] References Cited
U.S. PATENT DOCUMENTS
4,749,347 6/1988 Valavaara 425/135
5,121,329 6/1992 Cramp 364/468.26
5,141,680 8/1992 Almquist 264/401
Data corresponding to a desired shape of a prototype is transmitted to a rapid prototyping system. The system calculates a sequence for extruding flowable material that thermally solidifies so as to create the desired geometric shape. A heated flowable modeling material is then sequentially extruded at its deposition temperature into a build environment that maintains the volume in the vicinity of the newly deposited material in a deposition temperature window between the material's solidification temperature and its creep temperature. Subsequently the newly extruded material is gradually cooled below its solidification temperature, while maintaining temperature gradients in the geometric shape below a maximum value set by the desired part's geometric accuracy.
11 Claims, 3 Drawing Sheets
