3D printer

• US 10,583,604 B2
• Filed: 02/25/2015
• Issued: 03/10/2020
• Est. Priority Date: 02/25/2014
• Status: Active Grant

• Current Assignee: Seiichi Yuyama
• Original Assignee: Seiichi Yuyama
• Inventors: Yuyama, Seiichi
• Primary Examiner(s): Del Sole, Joseph S
• Assistant Examiner(s): Nelson, Jamel M
• Application Number:
  US15/120,537
• Publication Number:
  US 20170008230A1
• Time in Patent Office: 1,840 Days
• 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]
• CPC Class Codes: B29C 64/393 for controlling or regulating additive manufacturing processes
• CPC Class Codes: B29K 2055/02 ABS polymers, i.e. acrylonitrile-butadiene-styrene polymers
• CPC Class Codes: B29K 2067/046 PLA, i.e. polylactic acid or polylactide
• CPC Class Codes: B33Y 10/00 Processes of additive manufacturing
• CPC Class Codes: B33Y 30/00 Apparatus for additive manufacturing; Details thereof or accessories therefor
• CPC Class Codes: B33Y 50/02 for controlling or regulating additive manufacturing processes

Abstract

Provided is a 3D printer which can use pellets of various materials and produce a large molded object without requiring an inactive gas. The printer is equipped with: an extrusion apparatus, having a nozzle provided on a lower end side of a cylinder, a screw arranged in the cylinder and controllably rotated by a screw motor, a gear pump provided on a tip side of the screw and controllably rotated by a gear pump motor, a heater for heating an inside of the cylinder, and a hopper for supplying a resin material into the cylinder; a table apparatus positioned facing the nozzle of the extrusion apparatus; and a control apparatus for controlling discharge of a resin from the nozzle of the extrusion apparatus, and for controlling a movement of the extrusion apparatus and/or the table apparatus in X-axis, Y-axis, and Z-axis directions with respect to a reference plane. The extrusion apparatus and/or the table apparatus has a structure moved through position control in the X-axis, Y-axis, and Z-axis directions by the control apparatus.

Claims

1. A three-dimensional printer, comprising:

an extrusion apparatus including;

a cylinder with a cylinder heater, the cylinder receiving a resin material therein, and the cylinder heater fusing the resin material in the cylinder;

a screw arranged in the cylinder;

a screw motor for rotating the screw;

a gear pump with a gear pump heater, the gear pump being provided on a tip side of the screw;

a gear pump motor for rotating the gear pump; and

a nozzle with a nozzle heater; and

a control apparatus configured to control an amount of a fused resin discharged from a tip of the nozzle of the extrusion apparatus, by controlling a rotation of the screw and a rotation of the gear pump,

wherein the control apparatus is further configured to inversely rotate the screw and the gear pump by a predetermined amount such that the fused resin is prevented from dropping from the tip of the nozzle when the discharge of the fused resin is stopped during molding.

2. The three-dimensional printer according to claim 1, wherein the gear pump heater, the nozzle heater, and the cylinder heater are configured such that a heating temperature preset to the gear pump heater and the nozzle hater is higher than the heating temperature preset to the cylinder heater.

3. The three-dimensional printer according to claim 1, further comprising:

a first pressure gauge for measuring a first resin pressure at a tip position of the screw, the first pressure gage being provided on the tip side of the screw; and

a second pressure gauge for measuring a second resin pressure in the nozzle, the second pressure gage being provided on a discharge side of the gear pump,

wherein the control apparatus is further configured to control the discharge of the resin from the nozzle based on the first and second resin pressures measured with the first and second pressure gauges, respectively.

4. The three-dimensional printer according to claim 1, further comprising:

a pressure control apparatus provided in the nozzle, the pressure control apparatus controlling a pressure in the nozzle by changing a volume of an internal space of the nozzle.

5. The three-dimensional printer according to claim 4, wherein the pressure control apparatus includes a piston member configured to move forward and backward in a direction perpendicular to an axial direction of the nozzle, and the pressure control apparatus controls a movement of the piston member to change the volume of the internal space of the nozzle.

6. The three-dimensional printer according to claim 1, further comprising:

a table apparatus facing the nozzle of the extrusion apparatus; and

an XY positioning apparatus to which the extrusion apparatus is attached, the XY positioning apparatus being movable in the X-axis and Y-axis directions,

wherein the control apparatus is further configured to control a movement of the XY positioning apparatus and a movement of the table apparatus in the Z-axis direction.

7. The three-dimensional printer according to claim 1, further comprising:

a positioning apparatus to which the extrusion apparatus is attached, the positioning apparatus being movable in the X-axis, Y-axis, and Z-axis directions,

wherein the control apparatus is further configured to control a movement of the positioning apparatus.

8. The three-dimensional printer according to claim 1, further comprising:

a pressure control apparatus including a volume control member provided in the nozzle, the pressure control apparatus driving the volume control member so as to increase a volume of an internal space of the nozzle when the discharge of the fused resin is stopped.

9. A method for operating a three-dimensional printer having an extrusion apparatus including a cylinder with a cylinder heater, a screw inside the cylinder, a screw motor for rotating the screw, a gear pump with a gear pump heater, the gear pump being provided on a tip side of the screw, a gear pump motor for rotating the gear pump, a nozzle with a nozzle heater, and a controller for controlling a rotation of the screw and a rotation of the gear pump, the method comprising:

providing a resin material into the cylinder;

heating the cylinder to fuse the resin material in the cylinder;

rotating the screw to send a fused resin toward the nozzle;

rotating the gear pump to controllably discharge the fused resin through the nozzle;

heating the gear pump and the nozzle while discharging the fused resin;

controlling an amount of the fused resin discharged from a tip of the nozzle, by controlling the rotation of the screw and the rotation the gear pump; and

inversely rotating the screw and the gear pump by a predetermined amount such that the fused resin is prevented from dropping from the tip of the nozzle when the discharge of the fused resin is stopped during molding.

10. The method according to claim 9, wherein the resin material is provided in a form of a pellet.

11. The method according to claim 9, wherein a heating temperature preset for the gear pump and the nozzle is higher than a heating temperature preset for the cylinder.

12. The method according to claim 9, further comprising:

measuring a first resin pressure at a tip position of the screw;

measuring a second resin pressure in the nozzle at a discharge side of the gear pump; and

controlling the discharge of the resin from the nozzle based on the first and second resin pressures.

13. The method according to claim 9, further comprising:

controlling a pressure in the nozzle by changing a volume of an internal space of the nozzle.

14. The method according to claim 13, further comprising:

providing a volume control member in the nozzle; and

driving the volume control member such that the volume of the internal space of the nozzle is increased when the discharge of the fused resin is topped, thereby further preventing dripping of the fused resin.

15. The method according to claim 13, wherein the controlling the pressure in the nozzle includes:

providing a piston member in the nozzle; and

moving the piston member forward and backward in a direction perpendicular to an axial direction of the nozzle so as to change the volume of the internal space of the nozzle.

16. The method according to claim 9, further comprising:

controlling a position of the extrusion apparatus in the X-axis, Y-axis, and Z-axis directions.