TWI548537B - Three dimensional printer and method for adjusting working coordinate of platform thereof - Google Patents

Description

Method for correcting working coordinates of three-dimensional printing device and platform thereof

The present invention relates to a method of correcting the working coordinates of a printing device and a platform, and more particularly to a method for correcting the working coordinates of a three-dimensional printing device and its platform.

With the advancement of Computer-Aided Manufacturing (CAM), the manufacturing industry has developed a three-dimensional printing technology that can quickly create the original design concept. The three-dimensional printing technology is actually a series of rapid prototyping (RP) technology. The basic principle is that the laminate is manufactured by the rapid prototyping machine to form the cross-sectional shape of the workpiece by scanning in the XY plane. The Z coordinate is intermittently displaced as a layer thickness, eventually forming a solid object. Three-dimensional printing technology can limit the geometry, and the more complex parts show the superiority of RP technology, which can greatly save manpower and processing time. In the shortest time, 3D computer aided design (Computer-Aided Design) , CAD) software designed by the digital three-dimensional model is truly presented, not only touched, but also real feeling Get its geometric curve, you can test the assembly of the parts, and even perform possible functional tests.

In general, a three-dimensional printing apparatus for forming a three-dimensional article by the above rapid prototyping method is generally constructed by reading a digital stereo model to construct a solid object associated with the digital stereo model. However, the platform for carrying the built substrate in the three-dimensional printing device tends to be gradually skewed with respect to the horizontal plane over time, while the coordinates of the digital stereo model are not changed, so that the print head is still in accordance with the original plane. Coordinates are stacked on the platform to build the substrate, resulting in a printed solid object that is expected to drop, thus reducing the print quality and print yield of the three-dimensional printing device.

The invention provides a method for correcting a working coordinate of a three-dimensional printing device and a platform thereof, which can correct the problem of platform skew without manually adjusting the position of the platform.

A three-dimensional printing device of the present invention includes a platform, a print head and a control unit. The platform includes a bearing surface and a plurality of calibration points on the bearing surface. The print head is disposed above the platform and configured to move along a reference plane and along a normal to the reference plane. The control unit controls the print head to move from the reference plane to the platform to contact with the calibration point, so as to obtain a plane coordinate of each calibration point corresponding to the reference plane and a shortest distance from each calibration point to the reference plane, and according to the plane The coordinate and the shortest distance obtain a standard compensation value of the bearing surface corresponding to the reference surface, and correct a model coordinate of the digital stereo model information according to the coordinate compensation value. The control unit moves the print head according to the corrected model coordinates to print one of the information associated with the digital stereo model The solid object is on the bearing surface.

The method for correcting the working coordinates of a platform of the present invention is applicable to a platform including a bearing surface and a plurality of calibration points. The school site is located on the bearing surface. The above method includes the following steps. First, a moving member is controlled to move from a reference surface to a bearing surface to contact with a calibration point. Then, a plane coordinate corresponding to the reference plane and a shortest distance from each calibration point to the reference plane are calculated, and a target compensation value of the bearing surface corresponding to the reference plane is obtained according to the plane coordinate and the shortest distance. Then, a working coordinate of a job to be executed by the platform is corrected according to the coordinate compensation value.

Based on the above, the three-dimensional printing device of the present invention is adapted to control the print head to move from a reference plane to a plurality of calibration points on the platform before the print job is performed to obtain the load of the platform. The surface corresponds to a standard compensation value of the reference surface, and then a model coordinate of the digital stereo model information is corrected according to the coordinate compensation value, so as to move the printing head according to the corrected model coordinates to print the digital stereo associated with the digital image. A three-dimensional object of model information. In this way, the print head can be shifted to the correct working point according to the corrected model coordinates without affecting the printing yield and printing accuracy of the solid object due to the deflection of the platform. In other words, the present invention adjusts the model coordinates of the digital stereo model information by calculating the coordinate compensation value of the bearing surface corresponding to the reference surface to compensate for the skew of the platform.

In addition, the present invention further derives a method for correcting the working coordinates of the platform, which can control a moving part to move from a reference plane to the platform to contact with a plurality of calibration points on the platform before performing the work. Obtaining a standard compensation value corresponding to the reference surface of the platform, and correcting the platform according to the coordinate compensation value A working coordinate of the work performed. In this way, the calibration method of the present invention can manually shift the work piece to the correct working point according to the corrected model coordinates without manually adjusting the level of the platform, without affecting the work due to the deflection of the platform. Execution yield and execution accuracy. Thus, the present invention can achieve the effect of correcting the deflection of the platform without manually adjusting the level of the platform.

The above described features and advantages of the invention will be apparent from the following description.

100‧‧‧Three-dimensional printing device

110‧‧‧ platform

112‧‧‧ bearing surface

114a, 114b, 114c‧‧‧ school sites

114d, 114e, 114f‧‧‧ school location / metal gasket

120‧‧‧Print heads, moving parts

122‧‧‧Metal nozzle

124‧‧‧Power supply

126‧‧‧Metal calibration probe

130‧‧‧Control unit

200‧‧‧Computer host

D1, D2, D3, D4, D5, D6‧‧‧ shortest distance

H1‧‧‧ height difference

N1‧‧‧ normal direction

P _L ‧‧‧ datum

1 is a block diagram showing the working environment of a three-dimensional printing apparatus according to an embodiment of the invention.

2 is a block diagram of a three-dimensional printing apparatus in accordance with an embodiment of the present invention.

3A is a schematic diagram of a three-dimensional printing apparatus in accordance with an embodiment of the present invention.

3B is a schematic diagram of a three-dimensional printing apparatus in accordance with another embodiment of the present invention.

4 is a schematic view of the print head of the three-dimensional printing apparatus of FIG. 3B.

Figure 5 is a schematic illustration of the print head of Figure 4 in contact with a school point.

Figure 6 is a partially enlarged schematic view of the print head of Figure 4;

Figure 7 is a calibration of the working coordinates of a platform in accordance with an embodiment of the present invention. Schematic diagram of the process.

The above and other technical contents, features, and advantages of the present invention will be apparent from the following detailed description of the embodiments of the invention. The directional terms mentioned in the following embodiments, such as "upper", "lower", "front", "back", "left", "right", etc., are only directions referring to the additional schema. Therefore, the directional terminology used is for the purpose of illustration and not limitation. Also, in the following embodiments, the same or similar elements will be given the same or similar reference numerals.

1 is a block diagram showing the working environment of a three-dimensional printing apparatus according to an embodiment of the invention. Referring to FIG. 1, the three-dimensional printing apparatus 100 of the present embodiment is adapted to print a solid object according to a digital stereo model information. In this embodiment, the digital stereo model information may be a stereo digital image file, which may be constructed, for example, by a computer host 200 through computer-aided design (CAD) or animation modeling software. Cutting the digital stereo model information into a plurality of cross-sectional information, so that the three-dimensional printing device 100 can sequentially create a plurality of three-dimensional cross-section layers according to the cross-sectional information of the digital stereo model information, and the three-dimensional cross-sectional layers are stacked to form Three-dimensional object.

2 is a block diagram of a three-dimensional printing apparatus in accordance with an embodiment of the present invention. 3A is a schematic diagram of a three-dimensional printing apparatus in accordance with an embodiment of the present invention. Referring to FIG. 2 and FIG. 3A , in the embodiment, the three-dimensional printing apparatus 100 includes a platform 110 , a print head 120 , and a control unit 130 . The platform 110 includes a load bearing surface 112 and a plurality of calibration points 114a, 114b, 114c on the load bearing surface 112. The print head 120 is disposed above the platform 110 and configured to move along a reference plane P _L and along a normal direction N1 of the reference plane P _L . The control unit 130 is coupled to the platform 110 and the print head 120, respectively, and controls the position of the print head 120 corresponding to the calibration points 114a, 114b, 114c from the reference plane P _L respectively (such as the dotted line on the reference plane P _{L in} FIG. 3A). The position shown by the circle moves along the normal direction N1 toward the platform 110 to contact with the calibration points 114a, 114b, 114c to obtain the plane coordinates and the calibration position of the calibration points 114a, 114b, 114c corresponding to the reference plane P _L . The shortest distances D1, D2, D3 of the points 114a, 114b, 114c to the reference plane P _L .

In detail, the control unit 130 may, for example, first control the displacement of the print head 120 to the position corresponding to the calibration point 114a on the reference plane P _L , and then control the print head 120 to move to the platform 110 along the normal direction N1 to the school. contacting sites 114a, 114a to obtain a correction corresponding to the site of the reference plane P _L on plane coordinates and the correction site 114a to the reference plane P _L is the shortest distance D1. Then, the control unit 130, for example, controls the displacement of the print head 120 to the position corresponding to the calibration point 114b on the reference plane P _L , and then moves to the platform 110 along the normal direction N1 to contact with the calibration point 114b to obtain the calibration. site 114b corresponding to the reference plane and the coordinate plane P _L correction site 114b to the reference plane P _L is the shortest distance D2. Thereafter, the control unit 130 further controls, for example, the displacement of the print head 120 to the position corresponding to the calibration point 114c on the reference plane P _L , and then moves to the platform 110 along the normal direction N1 to contact with the calibration point 114c to obtain the calibration. site 114c corresponding to the reference plane P _L and a correction coordinate plane 114c site plane P _L to the shortest distance D3. It should be noted that in the present embodiment, the number of school points 114a, 114b, and 114c is three, so that a plane is defined by using three points. However, any person having ordinary skill in the art can set a required number of calibration points on the platform 110 according to actual needs, and the present invention does not limit the number of school points.

Then, the control unit 130 further obtains a coordinate offset of the bearing surface 112 corresponding to the reference plane P _L according to the plane coordinates obtained by the foregoing steps and the shortest distances D1, D2, and D3, that is, the plane of the bearing surface 112. The skew compensation value of the coordinates relative to the plane coordinates of the reference plane P _L . In this manner, the control unit 130 can correct a model coordinate of the digital stereo model information according to the coordinate compensation value, and then move the print head 120 according to the corrected model coordinates to print the three-dimensional model information associated with the digital stereo model information. The object is on the carrying surface 112. In this way, the print head 120 can be displaced to the correct working point according to the corrected model coordinates without affecting the print yield and print accuracy of the solid object due to the deflection of the platform 110. In other words, the present embodiment compensates the model coordinates of the digital stereo model information according to the coordinate compensation value of the bearing surface 112 corresponding to the reference plane P _L to deflect the platform 110 by adjusting the model coordinates of the digital stereo model information. Make compensation. Thus, in this embodiment, the effect of correcting the skew of the platform 110 can be achieved without manually adjusting the level of the platform 110.

Further, in the present embodiment, the print head 120 and each of the calibration points 114a, 114b, 114c are adapted to be electrically conductive to each other upon contact. For example, each of the school sites 114a, 114b, and 114c may be a metal calibration site, that is, the school sites 114a, 114b, and 114c on the carrier surface 112 are made of metal. Alternatively, in another embodiment of the present invention, the platform 110 itself is a metal platform, and the print head 120 may include a metal nozzle 122 coupled to a power source 124. When the print head 120 moves from the reference plane P _L to the platform 110, the control unit 130 turns on the power source 124 to electrically connect the print heads 120 to each other when they are in contact with the calibration points 114a, 114b, 114c. a contact signal, the control unit 130 is adapted to receive the contact signal and position the print head 120 according to the contact signal to obtain a plane coordinate and a school point of the calibration point 114a, 114b, 114c corresponding to the reference plane P _L The shortest distances D1, D2, D3 of 114a, 114b, 114c to the reference plane P _L .

3B is a schematic diagram of a three-dimensional printing apparatus in accordance with another embodiment of the present invention. 4 is a schematic view of the print head of the three-dimensional printing apparatus of FIG. 3B. Figure 5 is a schematic illustration of the print head of Figure 4 in contact with a school point. It should be noted that the three-dimensional printing device of the present embodiment is similar to the three-dimensional printing device shown in FIG. 3A. Therefore, the present embodiment uses the component numbers and parts of the foregoing embodiments, wherein the same reference numerals are used. The same or similar elements, and the description of the same technical content is omitted. For the description of the omitted part, reference may be made to the foregoing embodiment, and the description is not repeated herein. The differences between the present embodiment and the foregoing embodiments will be described below.

Referring to FIG. 3B to FIG. 5, in the embodiment, the calibration points 114d, 114e, and 114f may be a plurality of metal spacers 114d, 114e, and 114f as shown in FIG. 3B, which are respectively clamped on the platform 110 and located. On the bearing surface 112, a top surface of the metal spacers 114d, 114e, 114f is higher than the bearing surface 112 as shown in FIG. In this case, the platform 110 can be a glass platform or a platform of other insulating materials. Of course, the invention is not limited thereto. The print head 120 includes a metal nozzle 122 and a metal calibration probe 126 as shown in FIG. The metal calibration probe 126 can be coupled to the power source 124. When the control unit 130 controls the print head 120 to move from the reference plane P _L to the platform 110 along the normal direction N1 from the position of the calibration points 114d, 114e, 114f, respectively, the control unit 130 turns on the power source 124 to make the metal school The position probe 126 is electrically connected to each other when in contact with the calibration points 114d, 114e, and 114f, and generates a contact signal according to the position, and the control unit 130 receives the contact signal and positions the metal calibration probe 126 according to the contact signal. to obtain the correction which sites 114d, 114e, 114f corresponding to the reference plane P _L and a correction coordinate plane sites 114d, 114e, 114f to the reference plane P _L is the shortest distance D4, D5, D6.

Figure 6 is a partially enlarged schematic view of the print head of Figure 4; Referring to FIG. 5 and FIG. 6 , in the embodiment, the metal calibration probe 126 is disposed around the metal nozzle 122 , and the apex of the metal calibration probe 126 and the nozzle apex of the metal nozzle 122 have a The height difference h1 causes the metal calibration probe 126 and the metal nozzle 122 to not interfere with each other while performing their respective operations. That is to say, when the three-dimensional printing device performs the horizontal correction of the platform 110, the metal calibration probe 126 of the printing head 120 is used for the calibration, and when the printing operation is performed, the printing head 120 is utilized. The metal nozzle 122 extrudes the hot melt material and forms it on the bearing surface 112 to print a solid object. When the print head 120 moves from the reference plane P _L to the platform 110 to contact the calibration points 114d, 114e, 114f, the metal nozzle 122 does not touch the bearing surface 112 and interferes with the calibration of the platform 110, and when the metal When the nozzle 122 prints a solid object, the metal calibration probe 126 does not contact the carrier surface 112 and interferes with the progress of the three-dimensional printing operation.

FIG. 7 is a schematic flow chart of a method for correcting a working coordinate of a platform according to an embodiment of the invention. The three-dimensional printing apparatus 100 according to the previous embodiment The calibration method of the working coordinate of the platform may be derived. The calibration method of the embodiment may be applied to a platform 110, which may have a bearing surface 112 and a plurality of calibration points, and the calibration point may be as shown in FIG. 3A. The metal calibration points 114a, 114b, 114c on the bearing surface 112 may also be a plurality of metal spacers 114d, 114e, 114f as shown in FIG. 3B, which are respectively clamped on the platform 110 and located on the bearing surface 112. The top surface of the metal spacers 114d, 114e, 114f is higher than the bearing surface 112 as shown in FIG. It should be noted that the platform 110 to which the calibration method of the embodiment is applied may be the platform 110 of the three-dimensional printing apparatus 100 as shown in FIG. 3A and FIG. 3B, or any one of the bearing surfaces 112 to be corrected. The level of the platform. In the present embodiment, the same or similar elements will be designated by the same reference numerals.

The method for correcting the working coordinates of the platform 110 of the present embodiment includes the following steps: First, a moving member 120 is controlled to move from a reference plane PL to the carrying surface 112 to contact with the calibration point (step S110). In particular, the moving member 120 can be disposed above the platform 110 and configured to move along a reference plane P _L and adapted to move along a normal direction N1 of the reference plane P _L . In this embodiment, for example, a control unit can be used to control the moving member 120 to move from the position of the reference plane P _L corresponding to the calibration point to the platform 110 in the normal direction N1 to contact with the calibration point. Taking the embodiment of FIG. 3A as an example, the control unit may, for example, first control the displacement of the moving member 120 to the position corresponding to the calibration point 114a on the reference plane P _L , and then move to the position close to the platform 110 to contact with the calibration point 114a. Then, the moving member 120 is controlled to be displaced to the position corresponding to the calibration point 114b on the reference plane P _L , and then the moving member 120 is moved to the platform 110 to be in contact with the calibration point 114b. Thereafter, the moving member 120 is controlled to be displaced to the position corresponding to the calibration point 114c on the reference plane P _L , and then the moving member 120 is moved to the platform 110 to be in contact with the calibration point 114c. The above steps can be repeated until the moving member 120 moves from the reference plane P _L to the platform 110 to contact each of the calibration points.

According to the above, the moving component 120 of the embodiment can be electrically connected to each other when in contact with each calibration point, thereby generating a contact signal, and the control unit is adapted to receive the contact signal and position the moving component 120 according to the contact signal. . Thus, the correction can be calculated sites correspond to the reference plane P _L and a correction coordinate plane sites 114a, 114b, 114c respectively, to the reference plane P _L is the shortest distance D1, D2, D3, and based on the above-described plane coordinates and the shortest The distances D1, D2, and D3 obtain a landmark compensation value of the bearing surface 112 corresponding to the reference plane P _L (step S120). In detail, the control unit may first control the displacement of the moving member 120 to the position corresponding to the calibration point 114a on the reference plane P _L and move to the platform 110 to contact with the calibration point 114a to calculate the calibration point. P _L corresponding to the reference surface 114a of the coordinate plane and a correction plane site 114a to P _L is the shortest distance D1. Then, the moving member 120 is controlled to be displaced to the position corresponding to the calibration point 114b on the reference plane P _L and the moving member 120 is moved to the platform 110 to contact with the calibration point 114b to calculate that the calibration point 114b corresponds to the reference surface. P _L and a correction coordinate plane site 114b to the reference plane P _L is the shortest distance D2. Thereafter, the moving member 120 is controlled to be displaced to the position corresponding to the calibration point 114c on the reference plane P _L and moved to the platform 110 to contact with the calibration point 114c to calculate the plane of the calibration point 114c corresponding to the reference plane P _L . The coordinates and the shortest distance D3 from the school point 114c to the reference plane P _L . Then, according to the plane coordinates obtained by the foregoing calculation and the shortest distances D1, D2, D3, the target compensation value of the bearing surface 112 corresponding to the reference plane P _L is obtained, that is, the plane coordinate of the bearing surface 112 relative to the reference plane PL The offset compensation value of the plane coordinates.

Next, a work coordinate of the work to be performed by the platform 110 is corrected based on the coordinate compensation value (step S130). That is to say, after the control unit obtains the skew compensation value of the plane coordinate of the bearing surface 112 with respect to the plane coordinate of the reference plane P _L , the preset work of the next work to be performed by the platform 110 can be performed according to the coordinate compensation value. The coordinates are compensated and corrected so that the moving member 120 can be shifted to the correct working point according to the corrected working coordinate to perform the work without affecting the execution yield of the work to be performed due to the skew of the platform 110. And accuracy.

In summary, the three-dimensional printing device of the present invention is adapted to print a three-dimensional object according to a digital stereo model information, and the three-dimensional printing device controls the print head from a reference surface before performing the printing task. The platform moves to contact with a plurality of calibration points on the platform to obtain a standard compensation value corresponding to the reference surface of the platform, and then corrects a model coordinate of the digital stereo model information according to the coordinate compensation value. The print head is moved according to the corrected model coordinates to print a solid object on the bearing surface. In this way, the print head can be shifted to the correct working point according to the corrected model coordinates without affecting the printing yield and printing accuracy of the solid object due to the deflection of the platform. In other words, the present invention adjusts the model coordinates of the digital stereo model information by calculating the coordinate compensation value of the bearing surface corresponding to the reference surface to compensate for the skew of the platform. Thus, the present invention can achieve the effect of correcting the deflection of the platform without manually adjusting the level of the platform.

In addition, the present invention further derives a method for correcting the working coordinates of the platform, which can control a moving part to move from a reference plane to the platform before performing the work. Moving to contact with a plurality of calibration points on the platform to obtain a target compensation value corresponding to the reference surface of the platform, and correcting a working coordinate of the work to be performed by the platform according to the coordinate compensation value. In this way, the calibration method of the present invention can manually shift the work piece to the correct working point according to the corrected model coordinates without manually adjusting the level of the platform, without affecting the work due to the deflection of the platform. Execution yield and execution accuracy.

Although the present invention has been disclosed in the above embodiments, it is not intended to limit the present invention, and any one of ordinary skill in the art can make some changes and refinements without departing from the spirit and scope of the present invention. The scope of the invention is defined by the scope of the appended claims.

110‧‧‧ platform

112‧‧‧ bearing surface

114a, 114b, 114c‧‧‧ school sites

120‧‧‧Print head

122‧‧‧Metal nozzle

D1, D2, D3‧‧‧ shortest distance

N1‧‧‧ normal direction

P _L ‧‧‧ datum

Claims (12)

A three-dimensional printing device comprises: a platform comprising a bearing surface and a plurality of calibration points, wherein the calibration points are located on the bearing surface; a row of printing heads disposed above the platform, the printing head being configured Moving along a reference plane and moving along a normal direction of the reference plane; and a control unit coupling and controlling the platform and the print head, the control unit controlling the print head from the reference plane The platform is moved to contact with the calibration points to obtain a plane coordinate of each of the calibration points corresponding to the reference plane and a shortest distance from the calibration point to the reference plane, and according to the plane coordinates and The shortest distances obtain a standard compensation value of the bearing surface corresponding to the reference surface, and correct a model coordinate of the digital stereo model information according to the coordinate compensation value, and the control unit moves the printing according to the corrected model coordinates The head prints a solid object associated with the digital stereo model information on the bearing surface. The three-dimensional printing device of claim 1, wherein the control unit controls the print head to face the platform from a position corresponding to the calibration points from a direction along a normal direction of the reference surface Move to contact these school locations. The three-dimensional printing device as claimed in claim 1, wherein the print head and each of the calibration points are adapted to be electrically connected to each other during contact, so that the control unit is in the print head and each school When the contact is in contact, a contact signal is received, and the print heads are respectively positioned according to the contact signals to obtain the planar coordinates and the shortest distances. The three-dimensional printing device of claim 3, wherein each of the calibration points is a metal calibration point, and the print head comprises a metal nozzle. The three-dimensional printing device of claim 4, wherein the metal nozzle is coupled to a power source, and the control unit turns on the power source when the print head moves from the reference surface to the platform. The three-dimensional printing device of claim 4, wherein when the printing head moves from the reference surface to the platform, the metal nozzles are respectively in contact with each of the calibration points and electrically connected to each other, so that The control unit receives the contact signal when the metal nozzle contacts each of the calibration points. The three-dimensional printing device of claim 3, wherein the calibration points are a plurality of metal spacers, and are clamped on the platform and located on the bearing surface, the print head includes a metal nozzle and a a metal calibration probe, the metal calibration probe is in contact with each of the calibration points and electrically connected to each other when the print head moves from the reference surface to the platform, so that the control unit is in the metal calibration The contact signal is received when the needle contacts each of the school sites. The three-dimensional printing device of claim 7, wherein the metal calibration probe is disposed around the metal nozzle, and a vertex of the metal calibration probe and a nozzle vertex of the metal nozzle There is a height difference between them. A method for correcting a working coordinate of a platform is applicable to a platform including a bearing surface and a plurality of calibration points, wherein the calibration points are located on the bearing surface, the method comprising: controlling a moving component from a reference plane The bearing surface is moved to the school positions Point contact; calculating a plane coordinate corresponding to the reference plane and a shortest distance from each of the calibration points to the reference plane, and obtaining the bearing surface corresponding to the plane coordinates and the shortest distances a standard compensation value of the reference surface; and a working coordinate for correcting a work to be performed by the platform according to the coordinate compensation value. The method for correcting the working coordinates of the platform according to claim 9 , wherein the step of controlling the moving member to move from the reference surface to the bearing surface to contact the calibration points further comprises: controlling the moving component The bearing surface is moved to a position corresponding to the calibration points from a position corresponding to the calibration points from the reference in a normal direction of the reference plane. The method for correcting the working coordinates of the platform according to claim 9 further includes: receiving a contact signal when the moving member is in contact with each of the calibration points; and performing the printing head according to each of the contact signals Positioning to calculate each of the plane coordinates and each of the shortest distances. The method for correcting the working coordinates of the platform according to claim 11, wherein the step of receiving the contact signal when the moving member contacts each of the calibration points further comprises: providing a power source to the moving member to When the moving component is in contact with each of the calibration points, the moving component is electrically connected to each of the calibration points to generate the contact signal.