Method and device for controlling an irradiation system

Patent metadata

Field	Value
Publication number	US-9878497-B2
Application number	US-201414550439-A
Country	US
Kind code	B2
Filing date	Nov 21, 2014
Priority date	Nov 21, 2013
Publication date	Jan 30, 2018
Grant date	Jan 30, 2018

Abstract

A method for controlling an irradiation system ( 20 ) for use in an apparatus ( 10 ) for producing a three-dimensional work piece and comprising a plurality of irradiation units ( 22 a, 22 b ) a first and a second irradiation area ( 18 a, 18 b ) as well as an overlap area ( 26 ) arranged between the first and the second irradiation area ( 18 a, 18 b ) is defined on a surface of a carrier ( 16 ) adapted to receive a layer of raw material powder. A first irradiation area ( 22 a ) of the irradiation system ( 20 ) is assigned to the first irradiation area ( 18 a ) and the overlap area ( 26 ), and a second irradiation unit ( 22 b ) of the irradiation system ( 20 ) is assigned to the second irradiation area ( 18 b ) and the overlap area ( 26 ). If it is determined that a section (S) or a radiation pattern according to which radiation beams ( 24 a, 24 b ) emitted by the irradiation units ( 22 a, 22 b ) of the irradiation system ( 20 ) are guided over the layer of raw material powder received on the carrier ( 16 ) and/or a contour (C) of the three-dimensional work piece to be produced extend(s) into the first and the second irradiation area ( 18 a, 18 b ) defined on the surface of the carrier ( 16 ), said section (S) of the radiation pattern and/or said contour (C), in a splitting region of the section (S) of the radiation pattern and/or the contour (C) which is located in the overlap area ( 26 ) arranged between the first and the second irradiation area ( 18 a, 18 b ), is split into a first portion (S 1 , C 1 ) and a second portion (S 2 , C 2 ). The first portion (S 1 , C 1 ) of said section (S) of the radiation pattern and/or said contour (C) is assigned to the first irradiation unit ( 22 a ) and the second portion (S 2 , C 2 ) of said section (S) of the radiation pattern and/or said contour (C) is assigned to the second irradiation unit ( 22 b ).

First claim

The invention claimed is:

1. Method for controlling, by a control device an irradiation system for use in an apparatus for producing a three-dimensional work piece and comprising a plurality of irradiation units, the method comprising the steps of:
defining a first and a second irradiation area as well as an overlap area arranged between the first and the second irradiation area on a surface of a carrier adapted to receive a layer of raw material powder,
assigning a first irradiation unit of the irradiation system to the first irradiation area and the overlap area,
assigning a second irradiation unit of the irradiation system to the second irradiation area and the overlap area,
determining that a section of a radiation pattern according to which radiation beams emitted by the irradiation units of the irradiation system are guided over the layer of raw material powder received on the carrier and/or a contour of the three-dimensional work piece to be produced extend into the first and the second irradiation area defined on the surface of the carrier,
splitting said section of the radiation pattern and/or said contour, in a splitting region of the section of the radiation pattern and/or the contour which is located in the overlap area arranged between the first and the second irradiation area, into a first portion and a second portion,
assigning the first portion of said section of the radiation pattern and/or said contour to the first irradiation unit,
assigning the second portion of said section of the radiation pattern and/or said contour to the second irradiation unit;
forming the three-dimensional work piece with the irradiation system and wherein the control device performs the steps of the defining, the determining, and the splitting.

2. The method according to claim 1 , further comprising the steps of:
determining that a section of the radiation pattern according to which radiation beams emitted by the irradiation units of the irradiation system are guided over the layer of raw material powder received on the carrier and/or a contour of the three-dimensional work piece to be produced in its entirety is located in the overlap area arranged between the first and the second irradiation area, and
assigning said section of the radiation pattern and/or said contour to either the first or the second irradiation unit.

3. The method according to claim 2 ,
wherein the section of the radiation pattern and/or the contour which in its entirety is located in the overlap area arranged between the first and the second irradiation area is assigned to the first irradiation unit, if a predefined element of the section of the radiation pattern and/or the contour is located in a region of the overlap area closer to the first irradiation area, and/or wherein the section of the radiation pattern and/or the contour which in its entirety is located in the overlap area arranged between the first and the second irradiation area is assigned to the second irradiation unit, if a predefined element of the section of the radiation pattern and/or the contour is located in a region of the overlap area closer to the second irradiation area.

4. The method according to claim 1 , further comprising the steps of:
dividing the overlap area defined on the surface of the carrier into a plurality of partitioning regions, and
splitting the section of the radiation pattern and/or the contour which extend into the first and the second irradiation area defined on the surface of the carrier into a first portion and a second portion in a selected one of the plurality of partitioning regions, wherein the partitioning region wherein the section of the radiation pattern and/or the contour is split into a first portion and a second portion, in subsequent irradiation steps, is selected randomly or according to a predetermined order.

5. The method according to claim 1 , comprising at least one of the further steps:
adjusting the section of the radiation pattern and/or the contour which extend into the first and the second irradiation area defined on the surface of the carrier in order to increase or to decrease a distance between the first and the second portion of the section of the radiation pattern and/or the contour, and
controlling at least one of the first and the second irradiation unit so as to increase or to decrease the power of a radiation beam emitted by the first and/or the second irradiation unit in a part of said section of the radiation pattern and/or said contour adjacent to the splitting region of said section of the radiation pattern and/or said contour.

6. The method according to claim 1 , wherein at least one of the first and the second portion of the section of the radiation pattern and/or the contour which extend into the first and the second irradiation area defined on the surface of the carrier comprises a predetermined minimum number of predefined elements of said section of the radiation pattern and/or said contour.

7. The method according to claim 1 , wherein the first and the second irradiation unit are controlled in such a manner that the first and the second portion of the section of the radiation pattern and/or the contour which extend into the first and the second irradiation area defined on the surface of the carrier are successively irradiated with a radiation beam emitted by the first and the second irradiation unit, respectively.

8. The method according to claim 1 , wherein the radiation pattern contains a plurality of scan vectors, and wherein the section of the radiation pattern which extends into the first and the second irradiation area defined on the surface of the carrier is split into a first and a second portion between adjacent scan vectors, and/or
wherein the contour which extends into the first and the second irradiation area defined on the surface of the carrier is split into a first and a second portion at an intersection point arranged between a first scan point of the contour located in the first irradiation area and a second scan point of the contour located in the second irradiation area.

9. A device for controlling an irradiation system for use in an apparatus for producing a three-dimensional work piece and comprising a plurality of irradiation units, the device comprising:
a definition unit adapted to define a first and a second irradiation area as well as an overlap area arranged between the first and the second irradiation area on a surface of a carrier adapted to receive a layer of raw material powder,
a first assigning unit adapted to assign a first irradiation unit of the irradiation system to the first irradiation area and the overlap area, and to assign a second irradiation unit of the irradiation system to the second irradiation area and the overlap area,
a determining unit adapted to determine that a section of a radiation pattern according to which radiation beams emitted by the irradiation units of the irradiation system are guided over the layer of raw material powder received on the carrier and/or a contour of the three-dimensional work piece to be produced extend into the first and the second irradiation area defined on the surface of the carrier,
a splitting unit adapted to split said section of the radiation pattern and/or said contour, in a splitting region of the radiation pattern and/or the contour which is located in the overlap area arranged between the first and the second irradiation area, into a first portion and a second portion,
a second assigning unit adapted to assign the first portion of said section of the radiation pattern and/or said contour to the first irradiation unit and to assign the second portion of said section of the radiation pattern and/or said contour to the second irradiati

Assignees

• SLM Solutions Group AG

Inventors

• Schwarze Dieter
• Wiesner Andreas

Classifications

• B29C64/153

  using layers of powder being selectively joined, e.g. by selective laser sintering or melting · CPC title

• B29C64/393

  for controlling or regulating additive manufacturing processes · CPC title

• B23K26/342

  Build-up welding · CPC title

• B33Y50/02

  for controlling or regulating additive manufacturing processes · CPC title

• G05B15/02

  electric · CPC title