Device and method for forming a workpiece by means of 3-D extrusion
Abstract
The invention relates to a device and a method for forming a workpiece by 3-D extrusion, wherein the device is provided with three vertical spindles drivable by spindle motors, a horizontal work platform for the workpiece connected to the spindles, wherein the vertical position of the work platform at the position of the spindles is adjustable by these spindles, a displacing member for horizontal displacement of an extrusion head and a control member for controlling the spindle motors, the displacing member and the extrusion head, wherein the device comprises a measuring device for measuring the vertical position of the work platform at the spindles and the control member is configured to move the work platform close to the extrusion head, to measure the vertical position of the work platform at each spindle and to correct the vertical position of the work platform by means of the spindle motors. The extrusion head thus always moves parallel to the work platform.

Term
7.4 yearsleft in the term
Expires 4 February 2034.
- Priority and filed
- Granted
- Today
- Expires
10 claims: 4 independent, 6 dependent
- 1Conclusies 1. Inrichting voor het door middel van 3D-extrusie vormen van een werkstuk, waarbij de inrichting omvat:- een frame;- tenminste drie, zich op drie verschillende posities in het frame in verticale richting uitstrekkende, door middel van spilmotoren aandrijfbare spindels;- een zich hoofdzakelijk horizontaal uitstrekkend werkplatform voor het dragen van het werkstuk, waarbij het werkplatform met elk van de spindels is verbonden en waarbij de verticale positie van het werkplatform op de positie waar het werkplatform met één van de spindels is verbonden, door de betreffende spindel instelbaar is;- een met het frame verbonden verplaatsingsorgaan, dat is ingericht voor het in een hoofdzakelijk horizontaal bewegingsvlak verplaatsen van een drager;- tenminste één aan de drager bevestigde extrusiekop;- toevoermiddelen voor het aan de tenminste ene extrusiekop toevoeren van te extruderen materiaal;en - een besturingsorgaan voor het besturen van de spilmotoren, van het verplaatsingsorgaan, van de extrusiekop en van de toevoermiddelen, met het kenmerk, - dat de inrichting is voorzien van een meetinrichting voor het meten van de verticale positie van het werkplatform op in de nabijheid van de spindels gelegen meetposities;- dat het besturingsorgaan is ingericht voor het tot in de nabijheid van de drager doen bewegen van het werkplatform, het in elk van de meetposities meten van de verticale positie van het werkplatform en het door middel van de spilmotoren corrigeren van de verticale positie van het werkplatform opdat het werkplatform zich parallel aan het bewegingsvlak van de drager uitstrekt.
- 2Inrichting volgens conclusie 1, met het kenmerk, dat de meetinrichting aan het frame is bevestigd en is voorzien van tenminste drie meetorganen die elk in de nabijheid van een spindel zijn aangebracht.
- 3Inrichting volgens conclusie 2, met het kenmerk, dat de meetorganen zijn ingericht voor het meten van de verticale positie van de drager in elk van de meetposities en dat het besturingsorgaan is ingericht voor het achtereenvolgens naar de meetposities doen bewegen van de drager.
- 4Inrichting volgens conclusie 1, met het kenmerk, - dat de drager is voorzien van een meetorgaan voor het vaststellen van de hoogte van het werkplatform ten opzichte van de drager;- dat het besturingsorgaan is ingericht voor het naar de nabijheid van de drager doen bewegen van het werkplatform, het achtereenvolgens naar de meetposities doen bewegen van de drager, het in elk van de meetposities meten van de verticale positie van het werkplatform door middel van het meetorgaan en het door middel van de spilmotoren corrigeren van de verticale positie van het werkplatform opdat het werkplatform zich parallel aan het bewegingsvlak van de drager uitstrekt.
- 5Inrichting volgens conclusie 4, met het kenmerk, dat het meetorgaan is voorzien van een in verticale richting in een geleider beweegbare pen en van een detector die bij het naar boven bewegen van de pen ten opzichte van de geleider bij het bereiken van een vooraf bepaalde positie een signaal afgeeft.
- 6Inrichting volgens conclusie 4, met het kenmerk dat het meetorgaan een door middel van laser werkende afstandmeter omvat.
- 7Inrichting volgens één van de voorafgaande conclusies, met het kenmerk, dat het besturingsorgaan is ingericht voor het voorafgaande aan het vervaardigen van een product corrigeren van de verticale positie van het werkplatform.
- 8Inrichting volgens één van de voorafgaande conclusies, met het kenmerk, dat het verplaatsingsorgaan omvat:- een eerste en een tweede, zich beide hoofdzakelijk horizontaal aan weerszijden van de door de spindels bepaalde ruimte uitstrekkende primaire geleiderail;- een zich tussen de primaire geleiderails uitstrekkende, langs de primaire geleiderails beweegbare wagen, die is voorzien van een zich dwars op de primaire geleiderails uitstrekkende secundaire geleiderail, waarlangs de drager beweegbaar is;en - aandrijfmiddelen voor het langs de primaire geleiderails doen bewegen van de wagen en het langs de secundaire rails doen bewegen van de drager.
- 9Inrichting volgens conclusie 8, met het kenmerk, dat de aandrijfmiddelen een in het frame geplaatste primaire motor omvatten, die is gekoppeld met een primair getand wiel dat door middel van een primaire getande band verbonden is met de wagen en een in het frame geplaatste secundaire motor omvatten die is gekoppeld met een secundair getand wiel dat door middel van een secundaire getande band is verbonden met de drager.
- 10Werkwijze voor het parallel aan het bewegingsvlak van een extrusiekop van een 3D extrusiemachine brengen van een in door middel van spindels in verticale richting beweegbaar werkplatform, waarop het door de extrusiemachine te vervaardigen werkstuk wordt gevormd omvattende de volgende stappen:- het tot in de nabijheid van een drager waarop de extrusiekop geplaatst is, doen bewegen van het werkplatform, - het achtereenvolgens naar meetposities in de nabijheid van de spindels doen bewegen van de drager, het in elk van de meetposities meten van de verticale positie van het werkplatform en het door middel van de spindels corrigeren van de verticale positie van het werkplatform. 1/3
Independent claims10
39 paragraphs in 1 section, as filed
© Patent holder (s):
Leapfrog BV in Alphen ad Rijn.
<img file="NL2012198C2_D0001.tif" />
Patent granted:
06.08.2015 © Patent issued:
12.08.2015 © Inventor (s):
Martinus Petrus Otten in Amsterdam.
© Authorized representative:
ir. H.Th. van den Heuvel cs in 's-Hertogenbosch.
© Device for forming a workpiece by means of 3D extrusion.
The invention relates to a device and a method for forming a workpiece by 3D extrusion, wherein the device is provided with three vertical spindle motors that can be driven through spindle motors, a horizontal work platform for the workpiece connected to the spindles, wherein the vertical position of the working platform at the position of the spindles, adjustable by that spindle, a displacement member for horizontally displacing an extrusion head and a control member for controlling the spindle motors, the displacement member and the extrusion head, the device comprising a measuring device for measuring the vertical position of the working platform at the spindles and the control member adapted to move the working platform up to the extrusion head, measuring the vertical position of the working platform at each spindle and correcting the vertical position of the working platform by the spindle motors. The extrusion head thus always moves parallel to the working platform.
LC 2012 198
This patent is granted regardless of the enclosed result of the prior art research and written opinion. The patent corresponds to the documents originally filed.
Device for forming a workpiece by means of 3D extrusion.
In recent years, the use of 3D extrusion for the production of workpieces has increased significantly. This not only concerns the production of prototypes and models, but also, partly due to the falling prices of this technique, the production of small series.
The invention therefore relates to a device for forming a workpiece by means of 3D extrusion, wherein the device is provided with a frame, at least three, which can be driven vertically by means of spindle motors at three different positions in the frame. spindles, a mainly horizontally extending work platform for carrying the workpiece, the working platform being connected to each of the spindles and the vertical position of the working platform at the position where the working platform is connected to one of the spindles being adjustable by the respective spindle, a displacement member connected to the frame, adapted for moving a carrier, at least one extrusion head attached to the carrier in a substantially horizontal plane of movement, supply means for supplying material to be extruded to the at least one extrusion head and a control member for controlling the spindle motors, of the displacement member, of the extrusion head and of the supply means.
Such devices are generally known. The use of 3D printing requires movability of the extrusion head relative to the working platform, also referred to as a bed, in three directions. In the above-explained device, the working platform is device to move in the vertical direction and the extrusion head is arranged to move in both horizontal directions.
For the production of a workpiece with great precision, it is of great importance that the plane in which the extrusion head can move is parallel as much as possible to the plane of the work platform. After all, the digital model that moves the extrusion head has layers that are successively built up during movements of the extrusion head formed in a plane. If the substrate is not exactly parallel to the plane in which the extrusion head moves, there is a chance that the extrusion head will jam against the head or against already formed layers, or that the extruded material will not hit the substrate. In the prior art this is solved by forming the bottom layers of a workpiece of a removable, for instance water-soluble material, as is also used in this technique for filling recesses. The use of such a material requires the use of a device with at least two extrusion heads and associated auxiliary equipment, while it cannot be excluded that the initially applied layers of removable material form a substrate that extends completely parallel to the plane in which the extrusion head moves.
The present invention seeks to provide an apparatus of the above-mentioned type which, also using a single extrusion head, avoids the above-mentioned drawbacks.
This object is achieved by a device of the above-mentioned type, the device being provided with a measuring device for measuring the vertical position of the working platform at measuring positions located in the vicinity of the spindles and the control device being adapted to moving the working platform near the carrier, measuring the vertical position of the working platform in each of the measuring positions and correcting the vertical position of the working platform by means of the spindle motors so that the working platform extends parallel to the plane of movement of the carrier.
As a result of these measures, the working platform is brought into a position, extending parallel to the plane of movement of the extrusion head, so that the layers of extruded material are built up in parallel layers.
There are several options for implementing the invention. Thus, a first embodiment provides the possibility of attaching the measuring device to the frame in the form of at least three measuring members, each of which is arranged in the vicinity of a spindle. This embodiment assumes that the frame forms the reference and that the plane in which the displacement member moves extends parallel to a reference plane of the frame. This embodiment uses measuring members attached to the frame, the position of which is known relative to the frame reference plane, and which measures and corrects the position of the working platform when necessary.
The above embodiment uses the assumption that the plane of movement of the extrusion heads extends parallel to the reference plane of the frame. This does not always have to be the case. For the situation where this is indeed not the case, a further embodiment provides the measure that the measuring members are arranged for measuring the vertical position of the carrier in each of the measuring positions and that the control member is arranged for successively moving to the measuring positions of the wearer. Thus, both when determining the plane of movement of the extrusion heads and when determining the plane of the working platform, reference is made to the reference plane of the frame, so that any skew of the plane of movement of the extrusion heads is compensated for.
However, it is also possible to work without reference of the frame. To this end, another embodiment provides the measure that the carrier is provided with a measuring member for determining the height of the working platform relative to the carrier and that the control member is adapted to cause the working platform to move towards the wearer, successively moving the carrier to the measuring positions, measuring the vertical position of the working platform in each of the measuring positions by means of the measuring member and correcting the vertical position of the working platform by means of the spindle motors so that the working platform extends parallel to the plane of movement of the carrier. In this embodiment, a measurement is thus carried out between the parts of the device that actually determine the accuracy.
According to a first constructionally attractive embodiment, the measuring member is provided with a pin movable in a guide in a vertical direction and with a detector which emits a signal when the pin is moved upwards relative to the guide when it reaches a predetermined position. This is a simple, reliable and accurate way to measure the respective distance.
It cannot be ruled out that, in an alternative embodiment, the measuring member comprises a laser-operated distance meter. Laser-based measuring devices have recently become available at increasingly lower prices, so this form of rangefinder is a good alternative.
In order to increase the accuracy of the measurement procedure, it is preferred that the controller is arranged to correct the vertical position of the working platform prior to manufacturing a product. Calibration is hereby performed shortly before the moment when accuracy is of the utmost importance.
According to a constructionally attractive embodiment, the displacing member comprises a first and a second primary guide rail, which extend substantially horizontally on either side of the space defined by the spindles, a carriage which extends between the primary guide rails and which is movable along the primary guide rails. a secondary guide rail extending transversely of the primary guide rails, along which the carrier is movable and driving means for moving the carriage along the primary guide rails and moving the carrier along the secondary rails. This construction makes it possible to mount the measuring member on the underside of the carrier.
Yet another constructively attractive embodiment provides the measure that the drive means comprise a primary motor placed in the frame, which is coupled to a primary toothed wheel which is connected to the carriage by means of a primary toothed tire and a secondary motor placed in the frame which is coupled to a secondary toothed wheel connected to the carrier by a secondary toothed tire. This way of driving the carrier results in a low inertia, since the motors are both fixedly mounted in the frame and these relatively heavy parts do not have to be moved.
Finally, the invention provides a method for placing a work platform movable in the vertical direction by spindles parallel to the plane of movement of an extrusion head of a 3D extrusion machine, on which the workpiece to be manufactured by the extrusion machine is formed, comprising the steps of the moving the working platform in the vicinity of a carrier on which the extrusion head is placed, successively moving the carrier to measuring positions in the vicinity of the spindles, measuring the vertical position of the working platform in each of the measuring positions and correcting the vertical position of the working platform by means of the spindles. Application of this method leads to the same advantages as the use of the devices explained above.
The present invention will now be elucidated with reference to the annexed drawings, in which:
Figure 1: a schematic front view of a device according to the invention;
Figure 2: a schematic perspective view of the device shown in figure 1; and
Figure 3: a schematic cross-sectional view of an alternative embodiment.
The device shown in Figures 1 and 2 comprises a frame 1, which is shown in Figure 2 in the form of two vertical angle profiles 1a and 1b and a bar 1c connecting both profiles. It will be clear that in most cases the frame will be provided with corresponding corner profiles on the front of the device. However, it is also possible that the frame has the shape of a box in which the parts are placed. The frame 1 further comprises a bottom plate 2, on which, in the present case at each corner and on the center of the opposite side, a foot 3 is placed, in which a vertically extending spindle 4 is mounted. At their top, the spindles 4 are each mounted in an upper bearing 5, which is connected to the frame 1. An electric motor 6 acting as a spindle motor is arranged in each of the feet 3, which motor can drive the spindle 4 in rotation. A gear transmission can be arranged in the housing of the spindle motor 6. Above the base plate 2, a working platform 7 is arranged which extends horizontally as much as possible. The working platform 7 is connected to 3 nuts 8, through which the spindles 4 extend and are connected. Thus, when one of the motors 6 rotates, the spindle 4 connected thereto will rotate, whereby the nut 8 placed thereon moves vertically and the working platform 7 at the position of the nut 8 is adjusted in height and the working platform 7 will tilt. When the three spindle motors 6 are used synchronously, the working platform 7 will be moved in its entirety in the vertical direction.
For the application of the expanded material use is made of a displacement member indicated in its entirety by 10, which comprises two primary guide rails 11 extending horizontally and mutually parallel in the vicinity of the top end of the frame 1. Between these guide rails 11 a carriage 12 is arranged which is movable in the longitudinal direction of the primary guide rails 11 along the primary guide rails 11. A secondary guide wheel 13 is arranged in the longitudinal direction of the carriage 12, along which a carrier 14 is movable. The carrier 14 is provided on its underside with an extrusion head 15. Due to the combined movement of the carriage 12 along the primary guide rails 11 and of the carrier 14 along the secondary guide wheel 15, the extrusion head 15 can be moved over the entire surface of the working platform 7 . For driving the carriage 12 along the primary guide rails 11, use is made of an electric motor fixed to the frame, not shown in the drawings, which is connected to the carriage 12 by means of a toothed disc and toothed belt, which is also not shown. To drive the carrier 14 along the secondary guide wheel 13, use is made of an electric motor, not shown in the drawing, which is connected to the carrier 1 by means of a toothed disc and a toothed belt. This toothed belt is bi-directional along the carriage guided to decouple the movement of the carrier 14 from that of the carriage 12. Naturally, the device is provided with a control device in the form of a digital calculator, for controlling various electric motors and the extrusion head so that the desired product is formed. It will be clear to the skilled person that further means are provided for supplying material to be extruded to the extrusion head, as is known per se from the prior art. The device described so far corresponds to a device according to the prior art.
In order to obtain the effect of the invention, in the embodiment shown in Figures 1 and 2, the carrier 14 is provided on its underside with a probe 16 acting as a measuring element. This probe 16 is connected to the digital computer which is adapted for carrying out of the following procedure.
Prior to producing a new product or at any other desired time, the work platform 7 is brought to a position in proximity to the carrier 14. In many cases this will be the top position of the working platform 7. Subsequently, the carrier 14 is moved to a position in the vicinity of one of the spindles 4, and the distance between the carrier 14 and the working platform is measured at that position by means of the sensor 16 mounted on the underside of the carrier 14. This measurement is repeated in the vicinity of the other spindles 4. This provides information about the possible inclination of the working platform 7 with respect to the plane in which the carrier 14 and the extrusion head 15 moves therewith. Finally, the controller controls the spindle motors 6 such that the working platform 7 extends parallel to the plane of movement of the carrier 14. Subsequently, the product can be manufactured, the working platform 7 always continuing to extend parallel to the plane of movement of the carrier 14 by corresponding control of the spindle motors 6.
Figure 3 shows an embodiment in which the frame is provided with a top plate 20, on the underside of which three distance measuring members 21 are provided, of which only two are shown in the drawing. These distance measuring members 21 are arranged for measuring the distance between the relevant measuring member 21 and the working platform 7 under the control of the digital computer. It is then also possible for the digital computer to adjust the working platform 7 parallel to the top plate 20 by controlling the spindle motors 6. This embodiment assumes that the plane of movement of the carrier 14 extends parallel to the top plate 20, which will generally be the case. However, it is also possible to measure the position of the carrier 14 in the three relevant positions in the vicinity of spindles 4 by means of the measuring members 21, whereby any skew of the top plate 20 relative to the plane of movement of the carrier 14 is compensated for. .
It will be understood that various variations in the above embodiments can be made within the scope of the invention as defined by the appended claim. In particular, measures from different embodiments can be combined. It is further pointed out that the embodiments have three spindles, but that the invention is also applicable with two, four or more spindles. Instead of spindles, it is possible to use other controllable vertical displacement means.
12 sheets
Sheet 1 Sheet 2 Sheet 3 Sheet 4 Sheet 5 Sheet 6 Sheet 7 Sheet 8 Sheet 9 Sheet 10 Sheet 11 Sheet 12
Every citation, both ways
| Document | Relation | Office | Category | Cited during | Relevant claims |
|---|---|---|---|---|---|
| US10569522B2 | Cited by | United States of America | – | Applicant | – |
| US2013242317A1 | Cites | United States of America | A | Search report | 1-10 |
| EP2617554A1 | Cites | European Patent Office (EPO) | A | Search report | 1-10 |
4 members in 3 offices
Priority claims2
| Document | Office | Kind | Date |
|---|---|---|---|
| 2012198 | Netherlands (Kingdom of the) | A | |
| NL20142012198 | – | – | – |
Members4
| Document | Office | Kind | |
|---|---|---|---|
| EP2902175A1 | European Patent Office (EPO) | A1 | |
| NL2012198C2This record | Netherlands (Kingdom of the) | C2 | |
| US2015217519A1 | United States of America | A1 | |
| EP2902175B1 | European Patent Office (EPO) | B1 |
1 legal event, as the office reported them to INPADOC
Events
| Event | Code | |
|---|---|---|
| Lapsed because of non-payment of the annual feeLapsedMM | MM |
Numbers
- Publication
- 2012198
- Publication, DOCDB
- 2012198
- Publication, EPODOC
- NL2012198C
- Application
- 2012198
- Application, DOCDB
- 2012198
- Application, EPODOC
- NL20142012198
Titles2
- English
- DEVICE FOR FORMING A WORK BY 3D EXTRUSION.
- Dutch
- INRICHTING VOOR HET DOOR MIDDEL VAN 3D-EXTRUSIE VORMEN VAN EEN WERKSTUK.
Classification
- CPC, 7
- B29C64/106
- B29C64/232
- B29C64/236
- B29C64/393
- B33Y10/00
- B33Y30/00
- B33Y50/02
- IPC, 1
- B29C67 00