DEVICE FOR PROCESSING A BODY MANUFACTURED BY MEANS OF AN ADDITIVE MANUFACTURING

Abstract

A device (1) is for processing a body (4) manufactured by an additive manufacturing method from a liquid substance curable by radiation. The device (1) includes a holder (3) for a build platform (2). The device (1) also includes a separating device (5) for separating a body (4) arranged on a build platform (2) held by the holder (3) from the build platform (2), and a method and use employ the device.

Claims

1. A device for processing a body manufactured by an additive manufacturing method from a liquid substance curable by radiation, the device comprising a holder for a build platform, wherein the device comprises a separating device for separating a body arranged on the build platform held by the holder from the build platform.

2. The device according to claim 1, wherein the separating device comprises a shearing device, wherein the shearing device comprises a separating edge, wherein the device also comprises a drive for a relative movement between the holder and the shearing device.

3. The device according to claim 2, wherein the drive is configured to move the shearing device.

4. The device according to claim 2, wherein the drive is configured to move the holder.

5. The device according to claim 1, wherein the device comprises a stop for stripping and/or peeling off the body from the build platform.

6. The device according to claim 1, wherein the device comprises a force sensor which is configured to capture a force acting on the body during a separation.

7. The device according to claim 6, wherein the force sensor is connected to the separating device and is configured to capture a force exerted by the separating device.

8. The device according to claim 6, wherein the force sensor is connected to the holder and is configured to capture a force exerted by the holder.

9. The device according to claim 6, wherein the force sensor is connected to a processing unit for outputting process parameters based on the force signal.

10. The device according claim 6, wherein the force sensor comprises a strain gauge.

11. The device according to claim 1, wherein the device comprises a collecting unit which is arranged such that a body separated from the build platform using the separating device is collected in the collecting unit after separation.

12. The device according to claim 11, wherein the collecting unit is connected to a weight sensor, wherein the weight sensor is configured to capture the weight of a body collected by the collecting unit.

13. The device according to claim 11, wherein the collecting unit is connected to an actuator, wherein the actuator is configured to bring a receptacle of the collecting unit up to a body to be separated in at least one spatial direction.

14. The device according to claim 1, wherein the separating device is mounted to compensate for unevenness and/or positioning errors and/or incorrect positions or orientations of the build platform.

15. A method for processing a body manufactured by an additive manufacturing method from a liquid substance curable by radiation using a device according to claim 1, wherein a body arranged on a build platform held by the holder is separated from the build platform by the separating device.

16. The method according to claim 15, wherein the separating device comprises a shearing device, wherein the shearing device comprises a separating edge, wherein the device also comprises a drive for a relative movement between the holder and the shearing device, and wherein the body is sheared off from the build platform using the separating edge under the action of the drive.

17. The method according to claim 15, wherein the device comprises a force sensor, and during the separation of the body from the build platform, the force acting on the body is captured using the force sensor.

18. The method according to claim 16, wherein the drive for the relative movement between the holder and the shearing device is controlled based on a force signal from the force sensor.

19. A method for processing a body manufactured by an additive manufacturing method from a liquid substance curable by radiation, the device comprising a transport device comprising a drive for moving a build platform, the device comprising a stop for stripping and/or lifting the body off from the build platform, the method comprising stripping the body and/or lifting the body off from the build platform under the action of the drive over the build platform and under the action of the stop.

20. The device according to claim 6, wherein the force sensor is connected to a processing unit for outputting process parameters based on the force signal and/or for controlling a drive.

Description

[0055] The invention is explained in more detail in the following using preferred, non-limiting exemplary embodiments with reference to the drawings. Shown are:

[0056] FIG. 1 schematically a device according to the invention for processing a body manufactured by means of an additive manufacturing method from a liquid substance curable by radiation and for separating the body from a build platform using a separating device;

[0057] FIGS. 2A-C schematically a separation process, wherein in FIG. 2A, the separating device touches the body, in FIG. 2B, the body has been partially sheared off, and in FIG. 2C, the body is completely sheared off;

[0058] FIG. 3 schematically the device according to FIG. 1 at the moment when the body is collected in the collecting unit;

[0059] FIG. 4 schematically a device which is slightly modified with respect to FIG. 1 and has a light barrier which detects the complete detachment of the body from the build platform;

[0060] FIG. 5 schematically a diagram having an exemplary time profile of a force signal of a force sensor according to FIG. 1, for an already advanced but not yet fully completed separation process of a body from the build platform;

[0061] FIG. 6 schematically a diagram of the signal of the light barrier according to FIG. 4;

[0062] FIGS. 7A-C schematic diagrams of an adaptive speed control based on the force signal;

[0063] FIG. 8 schematically a diagram having a time profile of a force signal, which shows the complete separation of a component from the build platform;

[0064] FIGS. 9A and 9B schematic diagrams of a situation according to FIG. 2A in which a maximum predetermined separating force is exceeded and the separation process is terminated;

[0065] FIG. 10 schematically a build platform having a plurality of bodies which are separated by the shearing device and

[0066] FIG. 11 schematically the time profile of the force signal captured by the force sensor;

[0067] FIG. 12 schematically shows a build platform having residues which indicate an incomplete separation; and

[0068] FIG. 13 schematically a pivotable and spring-loaded mounting of a shearing device.

[0069] With reference to the above description and the terms used there, the elements of the specific, only exemplary embodiments shown in the drawings are: a device 1 for processing a body 4 manufactured by means of an additive manufacturing method from a liquid substance curable by radiation; a build platform 2; a holder 3 for the build platform 2, that is, which holds the build platform 2; a separating device 5 for separating a body 4 arranged on and adhering to the build platform 2 from the build platform 2; a shearing device 6 comprising a separating edge 7; a drive (not shown) for a relative movement between the holder 3 and the shearing device 6 along a direction of movement 8 of the shearing device 6; a force sensor 9; a light barrier 20; and contamination 21 adhering to the build platform, for example, in the form of a material residue.

[0070] The build platform 2 is mounted spring-loaded, horizontally displaceable and the force sensor 9 can capture the deflection of this suspension. The force sensor 9 is connected to the holder 3 and is configured to capture a force exerted by the holder 3, more precisely the counterforce applied by the spring-loaded mounting against the force of the drive of the shearing device 6. The force sensor 9 is connected to a processing unit 10 (connection line 11). The processing unit 10 can output process parameters on the basis of the force signal and control the drive of the shearing device 6 (connecting line 12). The force sensor 9 comprises a strain gauge.

[0071] The device 1 comprises a collecting unit 13. The collecting unit 13 is arranged such that a body 4 separated from the build platform 2 using the separating device 5 is collected in the collecting unit 13 after separation. In order to avoid damage to the body 4, padding is provided on the bottom of the collecting unit 13. The collecting unit 13 is connected to a weight sensor 14. The weight sensor 14 is configured to capture the weight of a body 4 collected by the collecting unit 13. The collecting unit 13 is also connected to an actuator 15, for example, to a rack (i.e. a linear gear). The actuator 15 is configured to bring a receptacle 16 of the collecting unit 13 in at least one spatial direction 17 to a body 4 to be separated (or to a build platform 2 supporting it). The separating device 5 is suitably mounted in order to compensate for unevenness and/or positioning errors and/or incorrect positions or orientations of the build platform 2, see mount 18 and spring 19 in FIG. 13.

[0072] The following terms were used in the diagrams: FN is the force signal captured by the force sensor 9; Fb is the suitable detachment force that can be applied by the shearing device 6 without causing damage to the body 4 or the build platform; tc is the point in time of the first contact of the shearing device 6 with the body 4; tsec is the time axis in seconds; LS is the signal from the light barrier 20; tsep is the point in time when the body 4 is completely separated from the build platform 2; xmm is the position of the shearing device 6 relative to the build platform 2 in millimeters; vm/s is the speed of the shearing device relative to the build platform 2; P is the power in watts; Psep is the specified detachment power to be regulated; tpeak is the point in time of the maximum force signal; Fstop is a maximum permissible force and a force threshold above which the separation process is interrupted due to an error; terror is the point in time at which an error occurs; xstop is the position of the shearing device 6 at the point in time time of the error; z is a Cartesian coordinate normal to the plane of the build area of the build platform 2 in a reference state (as shown in FIG. 1); Δz is a distance in the z coordinate; x and y are the coordinates in the plane of the build area.

[0073] In the illustrated figures, parts of the device that do not serve to describe the respective figure have been omitted for the sake of clarity.