LAYERED-MODELING DEVICE AND METHOD USING SAID DEVICE FOR MANUFACTURING THREE-DIMENSIONAL OBJECTS

• US 20120126457A1
• Filed: 05/14/2010
• Published: 05/24/2012
• Est. Priority Date: 05/15/2009
• Status: Active Grant

• Current Assignee: Panasonic Intellectual Property Management Co., Ltd. (Panasonic Holdings Corporation)
• Original Assignee: Panasonic Electric Works Company Limited (Panasonic Holdings Corporation)
• Inventors: Abe, Satoshi, Yoshida, Norio, Higashi, Yoshikazu, Fuwa, Isao
• Granted Patent: US 9,005,513 B2
• Time in Patent Office: Days
• US Class Current: 264/460
• CPC Class Codes: B22F 10/28 Powder bed fusion, e.g. selective laser melting [SLM] or electron beam melting [EBM]
• CPC Class Codes: B22F 10/32 of the atmosphere, e.g. composition or pressure in a building chamber
• CPC Class Codes: B22F 10/50 Treatment of workpieces or articles during build-up, e.g. treatments applied to fused layers during build-up
• CPC Class Codes: B22F 10/77 of gas
• CPC Class Codes: B22F 12/33 translatory in the deposition plane
• CPC Class Codes: B22F 12/41 characterised by the type, e.g. laser or electron beam
• CPC Class Codes: B22F 12/70 Gas flow means
• CPC Class Codes: B22F 12/90 Means for process control, e.g. cameras or sensors
• CPC Class Codes: B22F 2201/00 Treatment under specific atmosphere
• CPC Class Codes: B22F 2999/00 Aspects linked to processes or compositions used in powder metallurgy
• CPC Class Codes: B23P 15/00 Making specific metal objects by operations not covered by a single other subclass or a group in this subclass
• CPC Class Codes: B29C 64/153 using layers of powder being selectively joined, e.g. by selective laser sintering or melting
• CPC Class Codes: B29C 64/25 Housings, e.g. machine housings
• CPC Class Codes: B29C 64/268 using laser beams; using electron beams [EB]
• CPC Class Codes: B29C 64/364 Conditioning of environment
• CPC Class Codes: B33Y 30/00 Apparatus for additive manufacturing; Details thereof or accessories therefor
• CPC Class Codes: B33Y 40/00 Auxiliary operations or equipment, e.g. for material handling
• CPC Class Codes: B33Y 50/02 for controlling or regulating additive manufacturing processes
• CPC Class Codes: Y02P 10/25 Process efficiency

Abstract

An object of the present invention is to easily eliminate fumes inside a chamber, so as to improve a positional accuracy of irradiation with a light beam and a machining accuracy in a method for manufacturing a three-dimensional shaped object. A stacked-layers forming device 1 includes a powder layer forming unit 3, a light beam irradiating unit 4, a base 22 which is fixed and on which a powder layer 32 is formed, a lifting/lowering frame 34 which surrounds the circumference of the base 22 and is freely capable of being lifted and lowered, a cover frame 36 which has a window 36a allowing transmission of light beam in its top surface, and whose bottom surface is opened, and which is disposed on the lifting/lowering frame 34 to form a chamber C, and a gas tank 71 for supplying an ambient gas. The lifting/lowering frame 34 is lowered to reduce the volume of the chamber C, so as to discharge fumes generated inside the cover frame 36, which performs replacement with the ambient gas. Since the volume of the chamber C is reduced, it is possible to easily eliminate the fumes, which makes it possible to improve the positional accuracy of irradiation with the light beam L, and the machining accuracy.

Claims

1. A stacked-layers forming device for manufacturing a three-dimensional shaped object by forming a powder layer, and subsequently forming a solidified layer by irradiating the powder layer with a light beam in a chamber, the device comprising:

a base;

a lifting/lowering frame having a penetrating space, the penetrating space being communicated from one side to the other side and accommodating the base from the one side, the lifting/lowering frame being freely capable of being lifted and lowered with respect to the base;

a cover frame, the cover frame being disposed so as to cover the penetrating space on the lifting/lowering frame, and comprising a window allowing transmission of light beam in its top surface;

an ambient gas supply means for supplying an ambient gas;

a light beam irradiating unit, the light beam irradiating unit performing irradiation with a light beam via the window; and

a control unit, the control unit controlling lifting and lowering of the lifting/lowering frame with respect to the base, wherein

the chamber is constituted by a top surface of the base, an inner circumferential surface, specifying the penetrating space, of the lifting/lowering frame, and an inner surface of the cover frame, and

the control unit reduces a volume of the chamber by lowering the lifting/lowering frame to discharge fumes generated inside the chamber, and increases the volume of the chamber by lifting the lifting/lowering frame to supply an ambient gas from the ambient gas supply means.

2. The stacked-layers forming device according to claim 1, further comprising an exhaust port and an air supply port, the exhaust port and the air supply port being communicated with the chamber.

3. The stacked-layers forming device according to claim 1, wherein the discharge of the fumes and the supply of the ambient gas are controlled on the basis of an amount of the fumes inside the chamber.

4. The stacked-layers forming device according to claim 1, wherein the discharge of the fumes and the supply of the ambient gas are carried out on the basis of a time from a start of irradiation with the light beam.

5. The stacked-layers forming device according to claim 1, wherein a lowering speed and a lifting speed of the lifting/lowering frame and an amount of supplying the ambient gas during the discharge of the fumes and the supply of the ambient gas are controlled on the basis of a pressure inside the chamber.

6. The stacked-layers forming device according to claim 1, wherein a lowering speed and a lifting speed of the lifting/lowering frame and an amount of supplying the ambient gas during the discharge of the fumes and the supply of the ambient gas are controlled on the basis of an oxygen concentration inside the chamber.

7. The stacked-layers forming device according to claim 1, wherein the discharge of the fumes and the supply of the ambient gas are carried out during the irradiation with the light beam.

8. The stacked-layers forming device according to claim 1, further comprising a shutter covering a bottom surface of the window.

9. A method for manufacturing a three-dimensional shaped object, the method producing a three-dimensional shaped object by using a stacked-layers forming device that successively stacks some solidified layers by repeating a powder layer forming step of supplying an inorganic or organic powder material to form a powder layer, and a solidified layer forming step of forming a solidified layer by irradiating the powder layer with a light beam, thereby allowing sintering or melting and subsequent solidification of the powder layer, wherein

the stacked-layers forming device, comprising:

a powder layer forming means for executing the powder layer forming step;

a light beam irradiating unit for irradiating the powder layer with the light beam;

a base, the base being fixed and on a top surface side of the base the powder layer and the solidified layer being formed;

a lifting/lowering frame, the lifting/lowering frame surrounding an outer circumference of the base and being freely capable of being lifted and lowered with respect to the base;

a lifting/lowering drive means for lifting and lowering the lifting/lowering frame;

a cover frame, the cover frame comprising a window allowing transmission of light beam in its top surface, and a bottom surface of the cover frame being opened, and the cover frame being disposed on the lifting/lowering frame to form a chamber; and

an ambient gas supply means for supplying an ambient gas into the cover frame, wherein

a volume of the chamber is reduced by lowering the lifting/lowering frame to discharge fumes generated inside the cover frame, and

the volume of the chamber is increased by lifting the lifting/lowering frame to supply an ambient gas from the ambient gas supply means.

10. The method for manufacturing a three-dimensional shaped object according to claim 9, wherein the discharge of the fumes and the supply of the ambient gas are carried out via an exhaust port and an air supply port, the exhaust port and the air supply port being provided in the cover frame.

11. The method for manufacturing a three-dimensional shaped object according to claim 9, wherein the discharge of the fumes and the supply of the ambient gas are controlled on the basis of an amount of the fumes inside the chamber.

12. The method for manufacturing a three-dimensional shaped object according to claim 9, wherein the discharge of the fumes and the supply of the ambient gas are carried out on the basis of a time from a start of irradiation with the light beam.

13. The method for manufacturing a three-dimensional shaped object according to claim 9, wherein a lowering speed and a lifting speed of the lifting/lowering frame and an amount of supplying the ambient gas during the discharge of the fumes and the supply of the ambient gas are controlled on the basis of a pressure inside the chamber.

14. The method for manufacturing a three-dimensional shaped object according to claim 9, wherein the lowering speed and the lifting speed of the lifting/lowering frame and the amount of supplying the ambient gas during the discharge of the fumes and the supply of the ambient gas are controlled on the basis of an oxygen concentration inside the chamber.

15. The method for manufacturing a three-dimensional shaped object according to claim 9, wherein the discharge of the fumes and the supply of the ambient gas are carried out during the irradiation with the light beam.

16. The method for manufacturing a three-dimensional shaped object according to claim 9, wherein a shutter that covers a bottom surface of the window is closed during the discharge of the fumes and the supply of the ambient gas.