3D printer platform adjustment mechanism

Abstract

The invention relates to the 3D printer platform adjustment mechanism used in DLP, LCD, SLA type printers that perform additive manufacturing (Photopolymerization) by curing light-sensitive liquid polymer with actinic radiation and provides rotational movement of the printing plate in the X axis (X), Y axis (Y) and Z axis (Z) and additionally the translational movement in the Z axis (Z) direction, so that the printing plate (20) is parallel to the resin tank (110) bottom and the surfaces contact each other without any gaps at every point of the printing plate.

Description

[0001] 3D Printer Platform Adjustment Mechanism

[0002] Technical Field

[0003] The invention relates to the 3D printer platform adjustment mechanism used in DLP, LCD, SLA type printers that perform additive manufacturing (Photopolymerization) by curing light-sensitive liquid polymer with actinic radiation.

[0004] The invention particularly relates to a 3D printer platform adjustment mechanism that enables the freedom of rotation of the printing plate in 3 axes, namely X, Y, Z axes, and additionally the translational movement in the Z axis direction to be restricted and released by means of a single mechanism, so that the printing plate is parallel to the tank bottom and the surfaces contact each other without gaps at every point of the printing plate, and makes the calibration process simple and easy.

[0005] State of Art

[0006] Printers that perform additive manufacturing by curing the resin and form layers in order from the base to the top of the model are widely used, in these printers, a 3D (three-dimensional) model (object) is formed by adding first of the layers with a thickness corresponding to the desired resolution of the model in the Z-axis direction, first on the printing plate, and then adding each new layer one at a time onto the previously solidified layer. The model is formed as adhered to the printing plate and is then removed.

[0007] In the present applications, the working principle of printers that perform additive manufacturing by curing the resin, especially those that form layers in order from the base to the top of the model, is as follows; the resin is in a container whose base is made of a light-transmissive material. This container is called the resin tank. Resin is a light-sensitive liquid polymer. The production table, also called the printing plate, moves in the Z-axis direction and approaches the bottom of the tank containing the resin as much as the desired layer thickness. First, the base section of the object to be printed is projected as a solid / empty image onto a glass-bottomed tank filled with resin (photosensitive polymer resin) using a projector or LCD. Actinic radiation passing through transparent areas turns these areas into solid plastic. In SLA type printers, the layer to be cured is cured with a laser. Then the printing plate rises up, separates the bottom part of the object whose base is adhered to the printing plate from the resin tank base and approaches the resin tank base again as much as the desired layerthickness and cures the second section of the second image object, which is as thick as the layer thickness, from the base to the top, on the first. This process continues by curing a new layer each time over the previously formed layer until the part is completely formed.

[0008] In the state of art 3D printers, the resolution in the Z direction is related to how precisely the printing plate can be positioned in the Z direction. The resolution in the Z direction is equal to the layer thickness and can be achieved at values of 14 microns or even lower. Here, the resolution determines the precision and roughness of the model to be printed, making resin-based printers preferable to many other additive manufacturing methods.

[0009] A layer of resin is solidified by the printing plate, also called the production table, approaching the resin tank bottom each time by the resolution value, then turning on the actinic radiation source and masking it with a picture containing the object section to be formed (sections to be cured are tran spare nt / parts not to be cured are dark mask). Here, perfect parallelism of the printing plate to the resin tank bottom is important. Only under these conditions the details in that layer can be formed at the same height everywhere in the object section. The homogeneity of the layer thickness throughout the entire object cross-section is possible by having every point on the printing plate at equal distance from the resin tank bottom. Otherwise, instead of a homogeneous thick layer, a wedge-shaped section is cured or, if the given actinic radiation energy is not sufficient to cure the thick section, partial curing occurs in a part of the part section. In case of partial curing, the next layers on this layer do not provide good bonding and the model becomes deformed. Fully cured wedge-shaped sections also break part integrity and loyalty to the original model. In both cases, this expensive and time-consuming process is likely to be interrupted. Therefore, before starting the printing process, the perfect parallelism of the printing plate to the resin tank base should be checked. This control can be performed in 3 ways in printers that perform additive manufacturing by curing resin; I. Providing perpendicularity and parallelism between the resin tank, printer, actinic radiation source, printing plate and the mechanisms that provide the movement of the printing plate by the construction and there will be no need to adjust the parallelism of the printing plate and the resin tank bottom.

[0010] II. Ensuring the movement of the printing plate in the Z direction with the help of a mechanism. The printing plate is connected to this mechanism by one or more connection elements and / or shape connection methods, quick disconnect / install mechanisms. Before starting the 3D printing process, these connections and the mechanisms that keep the printing plate parallel to the base are loosened, and the printing plate is given freedom to rotate around 2 or 3 axes. The printing plate is pressed against the resin tank bottom with the help of the motion mechanism. When the loose printing plate is pressed down, it becomes parallel with the resin tank bottom. In this case, all connection elements are tightened and parallelism adjustment (calibration) is achieved.

[0011] III. Ensuring parallelism completely automatically with motors and force measurement sensors.

[0012] As well as it is theoretically possible to ensure the parallelism of the printing plate to the resin tank base through construction, it needs to be controlled and corrected (calibrated) due to tolerances arising from production methods, wear on the connection parts as a result of the operation of the printer, and especially when components with wide tolerance ranges are used due to the production method of the resin tank base. For this purpose, the connections on the bracket connecting the printing plate to the Z shaft are usually loosened, allowing the printing plate to rotate in 3 axes. However, in the present art, a mechanism was needed that would allow simple printing plate calibration.

[0013] The document numbered CN108312496 can be shown as an example of the state of the art in the research carried out in the literature. Said document relates to the 3D printing nozzle, platform and detection method of the 3D printer. In said document, a three-dimensional printer is described in which a strain gauge located next to the print head produces tension as it touches the table surface and the distance between the nozzle and the table is determined by the electronic circuit formed.

[0014] As a result, the existence of the above problems and the inadequacy of existing solutions have necessitated a development in the relevant technical field. Object of the Invention

[0015] The present invention relates to a 3D printer platform adjustment mechanism that eliminates the above-mentioned disadvantages and brings new advantages to the relevant technical field.

[0016] The main object of the invention is to present a adjustment mechanism that allows the printing plate to be parallel to the tank bottom and to have a gap-free contact between the surfaces at every point of the printing plate, allowing the printing plate to be free in 3 axes, namely rotational movement in the X, Y, Z axes, and additionally the translatory motion in the Z axis direction to be restricted and released by means of a single mechanism.

[0017] The object of the invention is to provide a adjustment mechanism that simplifies the calibration process of the printing plate.

[0018] In order to achieve the objects mentioned above and that can be derived from the detailed description, the invention is a 3D printer platform adjustment mechanism used in DLP, LCD, SLA type printers that perform additive manufacturing (Photopolymerization) by curing light-sensitive liquid polymer with actinic radiation, by comprising the following: main body, printing plate that is in contact with the lower surface of the main body and moves towards the resin tank comprising liquid resin,

[0019] - XY motion element in the shape of a hollow sphere located inside the main body and allowing the printing plate to rotate in the X axis, Y axis and Z axis during the calibration process,

[0020] Z motion shaft, which is located in the XY motion element and allows the printing plate to make translational movement in the Z axis during the calibration process,

[0021] - compression element placed inside the main body in such way that it grasps the XY motion element from the side and compresses the XY motion element in the main body and ensures that it is fixed after the calibration process, connection element that fixes the compression element to the main body and provides freedom of movement for the XY motion element and the Z motion shaft by loosening the compression element during the calibration process and by releasing the XY motion element, and restricts the freedom of movement for the XY motion element and the Z motion shaft by tightening the compression element and by pressing the XY motion element,

[0022] Z motion mechanism, which is fixed to the rear surface of the main body and allows the printing plate to move up and down to approach and move away from the resin tank, mounting bracket that connects the main body to the Z motion mechanism.

[0023] The structural and characteristic features of the invention and all its advantages will be understood more clearly by means of the figures given below and the detailed description written by making references to these figures. Therefore, the evaluation needs to be made by taking these drawings and detailed description into consideration.

[0024] Figures to Help Understand the Invention

[0025] Figure 1 : General view of the adjustment mechanism, which is the subject of the invention.

[0026] Figure 2: General view of the adjustment mechanism of the invention with the mounting cover open.

[0027] Figure 3: Disassembled view of the adjustment mechanism

[0028] Figure 4: Sectional view of the body of the adjustment mechanism, which is the subject of the invention.

[0029] Figure 5: View of the axes showing the direction of movement of the printing plate of the adjustment mechanism, which is the subject of the invention.

[0030] Description of Part References

[0031]

[0032] Detailed Description of the Invention

[0033] In this detailed description, the preferred alternatives of the adjustment mechanism, which is the subject of the invention are described only for the purpose of better understanding the subject and in a way that does not form any limiting effect.

[0034] The general view of the adjustment mechanism, which is the subject of the invention is given in Figures 1 and 2. Accordingly, the adjustment mechanism in its most basic form comprises the following; a main body (10), a printing plate (20) which is connected to the lower surface of the main body (10) and moves into the resin tank (110) containing liquid resin, an XY motion element (30) which enables the printing plate (20) to rotate in the X axis (X), Y axis (Y) and Z axis (Z) during the calibration process within the main body (10), a Z motion shaft (40) located in the XY motion element (30) and allows the printing plate (20) to make a translational movement in the Z axis (Z) during the calibration process, a compression element (50) which compresses the XY motion element (30) within the main body (10) and ensures its fixation after the calibration process, a connection element (60) that fixes the compression element (50) to the main body (10), the mounting cover (70) that is closed to the edge surface of the main body (10), a main body cover (80) closed on the main body (10), a Z motion mechanism (90) which is fixed to the rear surface of the main body (10) and allows the printing plate (20) to move up and down to approach and move away from the resin tank (1 10), a mounting bracket (100) that connects the main body (10) to the Z motion mechanism (90).

[0035] The printing plate (20) is connected to the lower surface of the main body (10), which forms the main structure of the adjustment mechanism, which is the subject of the invention. The main body (10) is connected to a vertical Z motion mechanism (90) by means of a mounting bracket (100) on its rear surface and moves up and down by means of the Z motion mechanism (90). Thus, the printing plate (20) is allowed to approach and move away from the resin tank (1 10) by moving up and down. The printing plate (20) moves into the resin tank (1 10) containing liquid resin and approaches the bottom of the resin tank to the distance required for the 3D (three- dimensional) model to form on it.

[0036] As seen in Figure 3, there is an XY motion element (30) inside the main body (10) that allows the printing plate (20) to rotate in the X axis (X), Y axis (Y) and Z axis (Z) during the calibration process. Said XY motion element (30) is a sphere made of spring steel, in which a hole similar to a circle cut from a beam is drilled through it along a diameter. The XY motion element (30) is also cut on its wall along the said hole. The Z motion shaft (40), which is cylindrical in shape and has a flange on one side and has the same cross section, passes through the cut circle shaped hole in the XY motion element (30). The hole in the XY motion element (30) and the cylinder shape of the Z motion shaft (40) do not allow rotation within the XY motion element (30), but do allow translation. Since there is a cut on the wall of the spherical XY motion element (30), when the XY motion element (30) is tightened with a force perpendicular to the hole axis, the Z motion shaft (40) that moves inside the XY motion element (30) and can make translational movement is compressed and its movement is prevented. Thus, during the calibration process, the printing plate (20), which makes a rotation movement in the X axis (X), Y axis (Y) and Z axis (Z) by means of the XY motion element (30), is also made to make a translation movement in the Z axis (Z) by means of the Z movement shaft (40).

[0037] A compression element (50) is placed inside the main body (10) so as to grasp the XY motion element (30) from the side. The said compression element (50) holds the XY motion element (30) within the main body (10) and at the same time compresses the XY motion element (30) within the main body (10) and ensures its fixation after the calibration process. The compression element (50) is clamped by fixing it into the main body (10) by means of at least one connection element (60). The connection element (60) is preferably a bolt.

[0038] By loosening the connection element (60), the printing plate (20) is given the freedom of rotation in the X axis (X), Y axis (Y) and Z axis (Z) by means of the XY motion element (30) and at the same time, the freedom of translation in the Z axis (Z) by means of the Z motion shaft (40) and thus the calibration process of the XY motion element (30) is carried out. By tightening the connection element (60), the compression element (50) puts pressure an the XY motion element (30). With the effect of this pressing force, the movement freedom of the XY motion element (30) and the Z motion shaft (40) within the XY motion element (30) is taken and the adjustment mechanism is locked.

[0039] In an alternative embodiment of the invention, the connection element (60) may be a ball-head bolt and the calibration of the printing plate (20) can be performed by the user in a single movement and without using a tool such as a screwdriver.

[0040] In another alternative embodiment, the connection element (60) that provides and restricts the freedom of the printing plate (20) can be adjusted not manually, but with a motor and via the printer control system. In this case, when the printing plate (20) is in its free state, the force applied to the resin tank (1 10) bottom is measured by sensors at different points and feedback is given to the control system, and when full parallelism is achieved, it gives the motor the command to tighten the connection element.

[0041] A mounting cover (70) is closed to the edge surface of the main body (10). A hole (71 ) is formed on the mounting cover (70) that allows the tool used to tighten and loosen the connection element (60) to reach the connection element (60).

[0042] In an alternative embodiment of the invention, if said connection element (60) is a bolt, there may be a handle on the connection element (60) and calibration (adjustment) can be performed by loosening or tightening the connection element (60) without tools.

[0043] The main body cover (80) is closed on the main body (10).

[0044] In the 3D printer, the resin tank (1 10) base is fixed and parallel to the ground plane on which the device fits. It is important for print quality to ensure that the printing plate (20) moving on the Z axis (Z) is parallel to the resin base in all cases. Only under these conditions can details in that layer can be formed at the same height everywhere in the object section. The uniformity of the layer thickness throughout the entire object cross-section is possible if every point on the printing plate (20) is at an equal distance from the bottom of the resin tank (110). For this purpose, the movable printing plate (20) must be placed on the resin tank (1 10) in a way that it can rotate freely and comfortably in 3 axes, namely X axis (X), Y axis (Y) and Z axis (Z), and at the same time, it can translate freely in the Z axis (Z).

[0045] During the operation of the 3D printer, the resin is cured in the space under the printing plate (20), which moves away from the resin tank (1 10) by the layer thickness each time in the Z axis (Z), after the first layer is solidified on the printing plate (20), it moves away from the resin tank in the Z axis (Z) direction and in the next operation, it approaches the bottom of the resin tank (110) again by the same amount of layer thickness and this time the new layer is cured on top of the previous layer. Thus, after multiple successive curings, the desired model to be printed is formed. The resolution of this model in the Z-axis (Z) direction is determined by the fact that the printing plate (20) approaches and moves away from the resin tank (110) by a certain multiple of a micron and by the same amount each time. This is guaranteed by perfect parallelism.

[0046] In the 3D printer, the printing plate (20) is approached and removed from the resin tank (1 10) bottom with the desired precision by means of a vertical Z motion mechanism (90). While it is possible to use rotation movement in 3 axes, namely X axis (X), Y axis (Y) and Z axis (Z), to ensure the parallelism of the printing plate (20) with the resin tank (1 10) base, it is not possible or very difficult to measure the equality of the resin tank base (1 10) and the printing plate at every point of their planes. However, when the printing plate (20) is freely left on the base of the resin tank (1 10), full parallelism is achieved without measuring. In accordance with this, in the invention, along with the freedom of rotation in 3 axes, the freedom of translation in the Z axis (Z) is also performed.

[0047] In the invention, the XY motion element (30) and the Z motion shaft (40) are placed in the spherical space that will form between them when the main body (10) and the compression element (50) are assembled, and then the body (10), the XY motion element (30), the Z motion shaft (40) and the compression element (50) are assembled to each other with two screws located on the flange at the front of the main compression element (50). When the connection element (60) on the other flange is not tightened, the XY motion element (30) and the Z motion shaft (40) can rotate in 3 axes, namely the X axis (X), Y axis (Y) and Z axis (Z), in the space formed by the main body (10) and the compression element (50), while the Z motion shaft (40) inside the spherical XY motion element (30) freely translates inside.

[0048] While the flanged end of the Z motion shaft (40) is prevented from falling under the effect of gravity when it is free inside the spherical XY motion element (30), the printing plate (20) is mounted perpendicular to the translation axis at the other end. In this case, the motion axes should be considered as the X axis (X) along the long side of the printing plate (20), the Y axis (Y) along the short side, and the Z axis (Z) along the Z motion shaft (40).

[0049] The flanges extending from the side of the compression element (50) are of different thicknesses. The flange tightened with two screws is thick and the flange using a single connection element (60) is thin. When a connection is made with two screws from the thick flange, the flange on the other side remains open and the XY motion element (30) can rotate in the spherical space between them and the Z motion shaft (40) can be shifted within the XY motion element (30). In this case, the printing plate (20) connected to the Z motion shaft (40) can rotate freely in the X axis (X), Y axis (Y) and Z axis (Z) with the freedom given by the XY motion element (30) and can also be translated in the Z axis. When the connection element (60) is tightened, the XY motion element (30) is compressed between the main body (10) and the compression element (50), compressing the Z motion shaft (40) moving inside it. Thus, both rotational movements and translational movements are restricted.

[0050] By means of the adjustment mechanism, which is the subject of the invention;

[0051] With the help of a single connection element (60), the printing plate can be given and restricted freedom of movement in 4 axes. By loosening the connection element (60), the printing plate (20) is given freedom of rotation in 3 axes, namely X axis (X), Y axis (Y) and Z axis (Z), and freedom of translation movement in the Z axis (Z). The printing plate (20) is lowered to the resin tank (1 10) bottom with the Z motion mechanism (90) and by means of the freedom of movement in a total of 4 axes, it freely touches the resin tank (1 10) at every point. When parallelism is achieved, the connection element (60) is tightened and the movement of the printing plate (20) in 4 axes at the same time is restricted. Thus, the calibration process is completed and the printer is ready for 3D printing. The freedom of movement in the Z axis (Z) direction is achieved without separating the printing plate (20) from the Z motion mechanism (90).

Claims

CLAIMS1. A 3D printer platform adjustment mechanism used in DLP, LCD, SLA type printers that perform additive manufacturing (Photopolymerization) by curing light-sensitive liquid polymer with actinic radiation, characterized by comprising: main body (10),- printing plate (20) that is connected to the lower surface of the main body (10) and moves towards the resin tank (110) comprising liquid resin, forming a 3D (three-dimensional) model,XY motion element (30) in the form of a hollow sphere, which is located inside the main body (10) and allows the printing plate (20) to rotate in the X axis (X), Y axis (Y) and Z axis (Z) during the calibration process, Z motion shaft (40), which is located in the XY motion element (30) and allows the printing plate (20) to make translational movement in the Z axis (Z) during the calibration process,- compression element (50), which is placed inside the main body (10) in such a way as to grasp the XY motion element (30) from the side and ensures that the XY motion element (30) is fixed after the calibration process by compressing it inside the main body (10),- connection element (60) that fixes the compression element (50) to the main body (10) and during the calibration process, by loosening through the compression element (50), allows movement freedom for the XY motion element (30) and the Z motion shaft (40) by releasing the XY motion element (30) through the compression element (50) and by tightening through the compression element (50), restricts the movement freedom for the XY motion element (30) and the Z motion shaft (40) by applying pressure to the XY motion element (30) through the compression element (50),Z motion mechanism (90), which is fixed to the rear surface of the main body (10) and allows the printing plate (20) to move up and down to approach and move away from the resin tank (1 10), mounting bracket (100) that connects the main body (10) to the Z motion mechanism (90).

2. The adjustment mechanism according to claim 1 , characterized by comprising; a mounting cover (70) which is closed to the edge surface of the said connection element (60).

3. The adjustment mechanism according io claim 1 , characterized by comprising; a hole (71) on the said mounting cover (70) which allows the tool used to tighten and loosen the connection element (60) to reach the connection element (60).

4. The adjustment mechanism according to claim 1 , characterized by comprising; a handle located on the connection element (60) that allows the connection element (60) to be loosened or tightened without tools.

5. The adjustment mechanism according io claim 1 , characterized by comprising; a motor and printer control system that allows said connection element (60) to be adjusted to provide and restrict the freedom of the printing plate (20).

6. The adjustment mechanism according to claim 1 , characterized by comprising; a main body cover (80) which is closed onto the said main body

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