Method and apparatus for in-situ formation of three-dimensional solid objects by extrusion of polymeric materials

• US 6,067,480 A
• Filed: 04/02/1997
• Issued: 05/23/2000
• Est. Priority Date: 04/02/1997
• Status: Expired due to Term

• Current Assignee: Stratasys Incorporated
• Original Assignee: Stratasys Incorporated
• Inventors: Hoffman, Robert A., Creegan, Peter J., Chambers, Gabriel C., O'Kelly, John A., Lombardi, John L., Calvert, Paul D., Stuffle, Kevin L.
• Primary Examiner(s): De Cady, Albert
• Assistant Examiner(s): ABRAHAM, ESAW T
• Application Number:
  US08/825,893
• Time in Patent Office: 1,147 Days
• Field of Search: 364/468.26, 364/468.25, 364/468.24, 700/109, 700/196, 264/168, 264/288.4, 239/133, 239/135, 239/227
• US Class Current: 700/109
• CPC Class Codes: B29C 64/106 using only liquids or viscous materials, e.g. depositing a continuous bead of viscous material
• CPC Class Codes: B29C 64/118 using filamentary material being melted, e.g. fused deposition modelling [FDM]

Abstract

An apparatus for thermal extrusion of a polymeric material to manufacture prototype mechanical elements from said polymeric material, said apparatus used for deposition of a liquefied ribbon of said polymeric material in patterned layers which solidify to form a three-dimensional prototype element, said apparatus comprising in combination, a mounting frame, said mounting frame including a mounting plate with a movable platen movable in the x and y directions, said frame further including an extrusion cylinder, said extrusion cylinder comprising a cylindrical housing having a uniform diameter cylindrical through passage, a head member having a uniform diameter bore connected with a reduced diameter, integral tip opening, said head member attached by a clamp to one end of the cylindrical housing to align the bore with the through passage, said-bore and through passage having an equal diameter, said head member including a circumferential heater to liquefy contents of the head member, a reciprocal piston slidably positioned in the cylindrical housing, and a piston actuator for driving the piston into the through passage to eject material through the tip opening.

Claims

1. An apparatus for thermal extrusion of a polymeric material to manufacture prototype mechanical elements from said polymeric material, said apparatus used for deposition of a liquefied ribbon of said polymeric material in patterned layers which solidify to form a three-dimensional prototype element, said apparatus comprising in combination:

a) a mounting frame, said mounting frame including a mounting plate with a movable platen movable in the x and y directions;

b) said mounting frame further including an extrusion cylinder, said extrusion cylinder comprising a cylindrical housing having a uniform diameter cylindrical through passage, a head member having a uniform diameter bore connected with a reduced diameter, integral tip opening, said head member attached by a clamp to one end of the cylindrical housing to align the bore with the through passage, said bore and through passage having an equal diameter, said head member including a circumferential heater to liquefy contents of the head member;

c) a reciprocal piston slidably positioned in the cylindrical housing; and

d) a piston actuator for driving the piston into the through passage to eject material through the tip opening of the head member.

2. The apparatus of claim 1 in combination with a cylinder of polymeric material taken from a group consisting of polyaryletherketone, polyurethane, polycarbonate and polymethyl methacrylate.

3. A method for forming prototype mechanical elements from polymer materials on a platform comprising the steps of:

a) positioning a cylindrical rod of said polymer material in a cylindrical housing having a through passage with a diameter substantially equal to the diameter of the cylindrical slug, said housing being connected with and attached to a discharge head member having a uniform diameter bore connecting with the through passage, a discharge tip, a reduced diameter discharge opening in the tip, and a circumferential heater to liquify the material in the bore;

b) compressing the material in the housing with a piston while simultaneously liquefying the material in the head member to thereby discharge a ribbon of material from the tip;

c) transporting the platform in the x and y directions while discharging material thereon to form the cross sectional shape of the element; and

d) transporting the housing and head member in the z direction simultaneously to form the element in elevation.

4. The method of claim 3 wherein the polymer material is from the group consisting of polyanyletherketone, polyurethane, polycarbonate and polymethyl methacrylate.

5. The method of claim 4 wherein the rod is compressed at a pressure of about 500 to 700 psi and the temperature of the polymer in the head member is in the range of about 180°

C. to 410°

C.