METHOD FOR ADDITIVE MANUFACTURE, AND SYSTEM

Abstract

A method for the additive manufacture of at least one three-dimensional object by means of a system, wherein a coating unit is moved onward through any number of segments and/or subsegments such that the coating unit performs at least one idle run. A system for the additive manufacture of three-dimensional objects, and a computer-readable storage medium are also disclosed.

Claims

1. A method for additive manufacturing of three-dimensional objects by a system comprising a build space, a build platform within the build space, on which the at least one object to be manufactured can be built up layer by layer, at least one coating unit for applying the build-up material layer by layer in a build plane which is provided parallel to the build platform, and at least a first irradiation unit and a second irradiation unit for locally selective solidification of the build-up material in the build plane, the method comprising: subdividing the build space into at least a first and a second segment along an extension direction of the build platform, wherein at least one of the segments is formed as a single segment or is subdivided into at least two subsegments and each segment or the subsegments of one of the segments assigned to one of the irradiation units; moving the at least one coating unit in the build space along the segments at a constant speed; applying at least one layer of the build-up material by using the at least one coating unit; activating the assigned irradiation unit in the respective segment or subsegment after the at least one layer of build-up material in the respective segment or subsegment is applied, the applied layer of build-up material is not yet selectively solidified and the at least one coating unit has left the segment or subsegment; and deactivating the application of build-up material by the at least one coating unit after the application of at least one layer of the build-up material, wherein the at least one coating unit is moved on through any number of segments or subsegments so that the at least one coating unit performs at least one idle run.

2. The method according to claim 1, wherein the respective irradiation unit is deactivated for a segment or a subsegment of a segment while the at least one coating unit passes through the respective segment or subsegment or after an irradiation time for selectively solidifying the deposited layer of build-up material in the respective segment or subsegment is reached.

3. The method according to claim 1, wherein a change in a relative position between the build platform and the at least one coating unit to provide a changed build plane occurs continuously or discontinuously.

4. The method according to claim 1, wherein the at least one coating unit starts depositing a further layer of build-up material in any selectively solidified segment or subsegment as a lowering segment when the at least one coating unit can accomplish a circulation for the application of a layer of build-up material without entering a not selectively solidified segment or subsegment.

5. The method according to claim 4, wherein the at least one coating unit deposits a complete layer of build-up material in the lowering segment subsequent to the remaining segments or subsegments.

6. The method according to claim 1, wherein activating the assigned irradiation unit occurs with: activating the associated irradiation unit in the respective segment for alternatively irradiating the associated first or second subsegment after the at least one coating unit has left the subsegment to be selectively solidified, wherein the at least one coating unit can pass through the first subsegment while the second subsegment is selectively solidified, or can pass through the second subsegment while the first subsegment is selectively solidified.

7. A system for additive manufacturing of three-dimensional objects by layer by layer application of a build-up material and locally selective solidification of the build-up material according to the method according to claim 1, comprising the build space, the build platform within the build space on which the at least one object to be manufactured can be built up layer by layer, the at least one coating unit for applying the build-up material (30) layer by layer in a build plane, which is provided parallel to the build platform, and at least the first irradiation unit and the second irradiation unit for locally selective solidification of the build-up material in the build plane, wherein the build space is subdivided in the extension direction of the build platform at least into the first segment and into the second segment, and at least one of the segments is formed as a single segment or at least one of the segments is subdivided into at least two subsegments, wherein each segment or the subsegments of a segment is assigned to at least one of the irradiation units, wherein, after the application of at least one layer of the build-up material, the application of build-up material by the at least one coating unit can be deactivated and the at least one coating unit can be moved further along the build plane through any number of segments or subsegments so that at least one idle run can be performed with the at least one coating unit.

8. The system according to claim 7, wherein the at least two segments or their subsegments form a closed path along the build plane, so that the at least one coating unit can be transferred via at least one further segment or its subsegments, from the first segment to the second segment and from the second segment to the first segment.

9. The system according to claim 7, wherein the single segments or their subsegments along the build platform are formed with identical size or have a comparable irradiation time for selective solidification of the applied layer of build-up material along the build plane so that a total irradiation time for selective solidification of at least one layer or a plurality of layers of the applied build-up material along all segments or subsegments in the build plane can be minimised.

10. The system according to claim 7, wherein the system is adapted to provide a relative movement to change a vertical relative position between the build platform and the at least one coating unit within the build space continuously or discontinuously.

11. The system according to claim 7, wherein depositing of a further layer of build-up material in any selectively solidified segment or subsegment as a lowering segment can be provided by the coating unit when the at least one coating unit can accomplish a circulation for applying a layer of build-up material without entering a not selectively solidified segment or subsegment.

12. The system according to claim 7, wherein the at least one coating unit is movable successively through the first subsegment and the second subsegment, wherein the first and second subsegments of the respective segment can be selectively solidified successively or alternately by the associated irradiation unit, wherein the first subsegment is passable for the at least one coating unit while the second subsegment can be selectively solidified, or the second subsegment is passable while the first subsegment can be selectively solidified.

13. The system according to claim 7, wherein the system comprises a control unit configured to control the movement or the duration of a circulation of the at least one coating unit and the application of build-up material by the at least one coating unit, an activation and deactivation of at least one of the irradiation units or the execution of a vertical relative movement between the build platform and the at least one coating unit within the build space.

14. A computer-readable storage medium having instructions for causing at least one processor of the control unit according to claim 13, to implement a method executed by the at least one processor.

Description

[0092] The invention is explained below in more detail with reference to the attached schematic drawings by reference to exemplary embodiments, which show in:

[0093] FIGS. 1a-7 schematic representations of various states during an exemplary sequence of the method according to the invention by means of a system according to the invention; and

[0094] FIG. 8 an exemplary embodiment of a system according to the invention for additive manufacturing of at least one three-dimensional object in a perspective sectional view.

[0095] FIG. 1a shows a schematic cross-sectional view of a build platform 10, which is subdivided into a total of four segments A; B; C; D. According to FIG. 1a, five selectively solidified layers are present on the build platform for forming at least one three-dimensional object 1.

[0096] The build plane 20 provided according to FIG. 1a is set on the uppermost, selectively solidified layer of build-up material 30 of the object 1 to be manufactured. A coating unit 40 according to FIG. 1a deposits a layer of build-up material 30 along the build-up plane 20 over the extension of the first segment A.

[0097] In accordance with FIG. 1a-7, a movement of the coating unit 40 is to be understood as a movement from left to right through the segments A to D along the build platform 10. Preferably, the segments A; B; C; D have comparable, in particular identical, irradiation times as required for selective solidification of applied build-up material 30.

[0098] A preferably ring-shaped design of the build platform 10 is illustrated in FIGS. 1 to 7 by the fact that the coating unit passes directly from the fourth segment D into the first segment A in order to perform a circular movement or a circulation.

[0099] FIG. 1b shows another exemplary embodiment in which the segments A; B; C; D according to FIG. 1a are each additionally subdivided into two subsegments A1; A2; B1; B2; C1; C2; D1; D2. The coating unit 40 may apply a layer of build-up material 30 along the subsegments A1; A2; B1; B2; C1; C2; D1; D2 to deposit a complete layer of build-up material 30.

[0100] In this regard, the subsegments A1-D2 of the segments A-D may have comparable, in particular identical, irradiation times as required for selective solidification of applied build-up material 30.

[0101] As compared to FIG. 1a, FIG. 2a shows an advanced state in the course of the depicted method. According to FIG. 2a, the coating unit 40 has applied at least one layer of build-up material 30.

[0102] Furthermore, FIG. 2a shows that the first, second and third segments A; B; C are selectively solidified by means of the respective assigned irradiation unit 50. In contrast, the fourth segment D in FIG. 2a is not selectively solidified due to the position of the coating unit 40 in the fourth segment 20 and the build-up material 30 still to be applied.

[0103] Respective progress indicators 52 along the segments A to C illustrate in FIG. 2a the progress of the selective solidification compared to the necessary irradiation time of the respective segments A; B; C. From these progress indicators 52 it is clear that selective solidification was started first in the first segment A or that selective solidification is more advanced than in the second and third segments B; C.

[0104] FIG. 2b illustrates the start of the selective solidification according to FIG. 2a on the basis of the subdivision of the segments A; B; C; D into two subsegments A1; A2; B1; B2; C1; C2; D1; D2 respectively according to FIG. 1b.

[0105] In particular, the subsegments A1; A2; B1; B2; C1; C2; D1; D2 of a respective segment A; B; C; D are assigned to a common irradiation unit 50 which can selectively solidify the subsegments A1; A2; B1; B2; C1; C2; D1; D2 of a segment A; B; C; D serially or alternately. Thus, in FIG. 2b it is shown that after the application of a complete layer of build-up material 30, the first subsegment A1; B1; C1; D1 of each of the segments A; B; C; D is selectively solidified.

[0106] The progress indicators 52 each indicate the progress of the selective solidification. Thus, it is shown that, according to FIG. 2b, the selective solidification of the first subsegment Al of the first segment A is completed until the coating unit 40 enters again. Subsequently, the second subsegment A2 of the first segment A is selectively solidified by means of the associated irradiation unit 40. During the progressive selective solidification along the segments A; B; C; D or the associated subsegments A1; A2; B1; B2; C1; C2; D1; D2, the coating unit 40 will perform an idle run.

[0107] After the first subsegments A1; B1; C1; D1 are selectively solidified, the individual irradiation units 50 may each proceed to selectively solidify the second subsegment A2; B2; C2; D2.

[0108] Furthermore, it is possible that the coating units 50 of the segments A; B; C; D can alternately selectively solidify the associated subsegments A1; A2; B1; B2; C1; C2; D1; D2 during the idle run of the coating unit 50, in order to allow the coating unit 50 to pass through preferably without interrupting the selective solidification. In this way, non-productive times can be reduced.

[0109] In FIG. 3, the coating unit 40 has entered the first segment A, whereupon the selective solidification by means of the assigned irradiation unit has been suspended or temporarily deactivated. Due to the up to FIG. 3 incomplete selective solidification of the first segment A according to the progress indicators 52, the selective solidification can be resumed or continued after the coating unit 40 has been moved out of the first segment A.

[0110] An already completed, temporarily suspended selective solidification of build-up material 30 in the first segment A is illustrated by a partially or sectionally reduced layer thickness, according to the progress indicators 52, and the at least temporarily deactivated irradiation unit 50.

[0111] Furthermore, according to FIG. 3, the selective solidification of the build-up material 30 in the fourth segment D has been initiated by means of the assigned irradiation unit 50.

[0112] Furthermore, it can be seen from FIG. 3 that the coating unit 40 is still located in the same build plane 20 compared to FIGS. 1a and 2.

[0113] In FIG. 4, the further progress of the selective solidification in all four segments A; B; C; D can be seen from the respective progress indicators 52. Due to the position of the preferably continuously moving coating unit 40 in the third segment C, the selective solidification in the third segment C is temporarily deactivated or suspended.

[0114] In FIG. 5, the first segment A has already been selectively solidified and the irradiation time as required has already expired, while the other segments B; C; D are still being irradiated, in particular until the irradiation time provided as required for each segment B; C; D has expired.

[0115] In FIG. 6, the build plane has already been readjusted by changing the vertical relative position between the coating unit 40 and the build platform 10, in particular by spacing them further apart in the vertical direction. According to FIG. 6, the application of a further layer of build-up material 30 has begun in the first and second segments A; B, even if the selective solidification of the previously deposited layer of build-up material 30 has not yet been completed in the remaining segments C; D (cf. also FIG. 5).

[0116] The first segment A thus represents a lowering segment. In particular, in the first segment A as a lowering segment according to FIG. 6, no complete layer of build-up material is applied over the entire extension of the first segment A. Rather, the first segment A is only partially covered with a layer of build-up material 30.

[0117] It can be seen from FIG. 6 that the first segment A is only partially covered with build-up material 30 in the readjusted build plane 20. The coating unit 40 enters into the second segment B for the application of a further layer of build-up material 30 in an, in particular, continuous movement and coordinated with the expiry of the irradiation time of the second segment B as required. By means of this timing of selective solidification and the application of a new layer of build-up material 30, the non-productive times of the manufacturing method or the production method for the at least one three-dimensional object 1 are reduced.

[0118] FIG. 7 shows that in the second and third segments B; C, in which a new, complete layer of build-up material 30 has been applied, selective solidification by the associated irradiation unit 50 has already begun. In contrast, no selective solidification is performed in the only partially coated first segment A as a lowering segment until the coating unit 40 has deposited a complete layer of build-up material 30 over the entire extension of the first segment A in the following circulation. After application of the build-up material 30 over the entire extension of the first segment A as a lowering segment, a complete layer of build-up material is present along the adjusted build plane 20.

[0119] Provided that selective solidification of the complete layer of build-up material in the subsequent segments B; C; D has not yet progressed to such an extent that a readjustment of the build plane and/or the deposition of a new layer of build-up material 30 can take place, the coating unit 40 subsequently switches into the idle run, i.e. the travel without applying a layer of build-up material 30.

[0120] In this sense, the lowering segment may move across each of the segments A; B; C; D or subsegments A1-D2, in the course of changing the relative position between the coating unit 40 and the build platform 10 to provide a readjusted build plane 20.

[0121] In FIG. 8, an examplary embodiment of a system according to the invention for additive manufacturing of at least one three-dimensional object 1 is shown in a perspective cross-section.

[0122] The system comprises the build platform 10, above which a build space is formed for the layer-by-layer construction of at least one three-dimensional object 1. In particular, one three-dimensional object 1 or a plurality of three-dimensional objects 1 distributed along the annular or circular extension of the build platform 10 can be built up layer by layer.

[0123] The coating unit 40 is arranged above and vertically spaced from the build platform 10 and can apply or deposit build-up material 30 along the respective set build plane 20 in the sense of a layered construction.

[0124] Irradiation units 50 are arranged above and vertically spaced from the coating unit 40 and distributed over the extension of the annular build platform 10. In particular, the irradiation units 50 are each assigned and arranged to the segments A; B; C; D for selective solidification.

[0125] In summary, the targeted use of the irradiation units 50 and the coating unit 40, which completes idle runs as required, enables time-optimised manufacture of at least one three-dimensional object 1. By means of the idle runs of the coating unit 40, in particular when the coating unit 40 is moving at maximum speed, an interruption of the selective solidification in the single segments A; B; C; D or in the single subsegments A1; A2; B1; B2; C1; C2; D1; D2 can be kept to a minimum during the passage of the coating unit 40 and a preferably continuously ongoing manufacturing process can be provided.

[0126] Along these lines, the parallel deposition of build-up material 30 and the selective solidification along sections or segments A-D and/or subsegments A1; A2; B1; B2; C1; C2; D1; D2 in the adjusted build plane 20 make it possible to reduce the non-productive times for additive manufacturing, to optimise the efficiency of the system utilisation in the production of three-dimensional objects 1, in particular also of a single large three-dimensional object 1, and to ensure a sufficient quality of the resulting three-dimensional object 1.

LIST OF REFERENCE SIGNS

[0127] 1 object to be manufactured/processed layers of build-up material

[0128] 10 build platform

[0129] 20 build plane

[0130] 30 layer of build-up material to be applied

[0131] 40 coating unit

[0132] 50 activated irradiation unit

[0133] 52 progress indicators

[0134] A; B; C; D segments

[0135] A1; A2 subsegments of the first segment

[0136] B1; B2 subsegments of the second segment

[0137] C1; C2 subsegments of the third segment

[0138] D1; D2 subsegments of the fourth segment