WO2022102896A1

WO2022102896A1 - Method for manufacturing curved molded article using 4d printing technology

Info

Publication number: WO2022102896A1
Application number: PCT/KR2021/007179
Authority: WO
Inventors: 박근
Original assignee: 서울과학기술대학교 산학협력단
Priority date: 2020-11-13
Filing date: 2021-06-08
Publication date: 2022-05-19
Also published as: KR102358094B1

Abstract

A method for manufacturing a curved molded article using 4D printing technology according to the present invention comprises: using a heating nozzle in a material extrusion-type 3D printer to set a printing path in a circumferential direction on a workbench of the 3D printer, and forming a 2.5D planar printed article in the form of a closed curve; using a heat supply device to position the planar printed article inside the heat supply device and position, on the planar printed article, a fixture provided in the heat supply device and corresponding to a curved shape; and in a state in which the temperature of the heat supply device is maintained at or above the heat deflection temperature of the planar printed article, inducing bending deflection of the planar printed article toward the periphery of the fixture while transferring heat from the heat supply device to the planar printed article, and thereby forming a 3D curved part in a shape corresponding to the fixture.

Description

Manufacturing method of curved molded products using 4D printing technology

The present invention relates to a method for manufacturing a curved part using 4D printing technology in which heat is applied to a closed curved planar part printed by a specific path in a material extrusion type 3D printer. is about

In general, a material extrusion or fused deposition modeling (FDM) 3D printer (hereinafter referred to as a '3D printer') uses an external computer to create a 3D modeling model for printing and uses an external computer to create a 3D printer. After making machine instructions (= G-Code) to repeatedly cut 3D sculptures into thin slices to produce individual thin slices, receive machine instructions from an external computer and move the heating nozzle according to the machine instructions to write the 3D modeling model on the workbench. Print the corresponding extruded output.

To this end, from a structural point of view, the 3D printer 60 schematically includes a workbench 10 , a heating nozzle 20 , an extruder 30 , and a filament spool 50 , as shown in FIG. 1 . Before the operation of the 3D printer 60 , the filament take-up 50 is wound into a long and thin line made of a plastic filament 72 in the 3D printer 60 . During operation of the 3D printer 60 , the 3D printer 60 is electrically connected to an external computer so that the 3D printer 60 drives the plastic filament 72 from the filament take-up 50 toward the extruder 30 . transmit

The plastic filament 72 is transferred from the extruder 30 to the heating nozzle 20 and melted inside the heating nozzle 20 through the heating nozzle 20 to a high-temperature

plastic line

73 or 75 in Figs. 2 is transformed as The plastic filament 72 is a thermoplastic resin, and may be acrylonitrile butadiene styrene (ABS) or polylactide (PLA).

The

plastic line

73 or 75 is printed on the work bench 10 as shown in FIG. 1 or 2 through the movement of the X and Y axes of the work table 10 and the Z axis movement of the heating nozzle 30 . Similarly, the

plastic line

73 or 75 may be printed on the workbench 10 through the movement of the Z-axis of the workbench 10 and the movement of the X-axis and Y-axis of the heating nozzle 30 . For example, the 3D printer 60 moves the work bench 10 and the heating nozzle 20 according to the machine language (= G-Code) of the external computer to produce a star-shaped extruded printout on the work bench 10 ; 80) can be printed as shown in FIG. 3 .

Here, the extruded output 80 is made by combining five diamond shapes 79 . The individual diamond shapes 79 include a plurality of first output plates ( 74 in FIG. 2 or 3 ) and a plurality of second output plates ( 74 in FIG. 2 or 3 ) positioned on the plurality of first output plates 74 . 76). The individual first output plates 74 are formed by repeatedly horizontally printing a plurality of plastic lines 73 along the transverse direction. The individual second output plates 76 are formed by repeatedly and vertically printing a plurality of plastic lines 75 along the longitudinal direction.

After the extruded output 80 is printed in a star shape on the workbench 10, the extruded output 80 has a compressive residual stress in the longitudinal direction in the individual first output plate 74, and the individual second output The plate 76 has a tensile residual stress in the longitudinal direction. That is, the individual first output plate 74 and the individual second output plate 76 have residual stresses opposite to each other in the longitudinal direction in the extruded output 80 .

Thereafter, the extruded output 80 may be separated from the workbench 10 and converted from a star shape to another shape by applying 4D printing technology. The 4D printing technology is performed to transform the initial shape of the extruded output 80 over time by applying an environment or energy source such as heat, vibration, gravity, or air to the extruded output 80 of the 3D printer 60. . Here, the 4D printing technology focuses on applying heat to the extruded output 80 in order to simplify the description of the present invention.

The extruded output 80 is subjected to heat application at 150° C. for 15 minutes in 4D printing technology to induce longitudinal expansion of the individual first output 74 and contraction in the longitudinal direction of the individual second output 76 according to time. While showing the movement of the starfish in the five diamonds 79, the free ends of the individual diamonds 79 are bent toward the center of the star shape and transformed into a curvedly-molded matter 85 as shown in FIG. 3 .

The bending molding 85 is effective only in a shape having a free end or an open end, such as the extruded product 80 of FIG. 3 due to a relationship based on bending deformation. In addition, since the bent molding 85 is formed by irregularly bending the free ends of the individual diamonds 79 in the extrusion output 80 , the shape of the bent molding 85 does not have consistency, reproducibility, and uniformity.

On the other hand, the manufacturing method of the bent molding is similarly disclosed as a prior art in Korean Patent Publication No. 10-1885474.

The present invention has been devised to solve the problems of the prior art, and is a curved molded product made by bending a flat output by applying heat to a 2.5D planar part of a closed curve printed by a material extrusion type 3D printer. An object of the present invention is to provide a method for manufacturing a curved molded product using 4D printing technology suitable to have consistency, reproducibility, and uniformity with respect to the shape of a curved part.

A method for manufacturing a curved molded article using a 4D printing technology according to the present invention is a printing path in a circumferential direction on a workbench of the 3D printer using a heating nozzle in a material extrusion type 3D printer. to form a 2.5D planar part of a closed curve shape, and using a heat supply device to position the planar output device inside the heat supply device, which is provided in the heat supply device to correspond to the curved shape A fixture is placed on the planar output while the heat is transferred from the heat supply to the planar output while maintaining the temperature of the heat supply above the heat deflection temperature of the planar output. and inducing bending deformation of the flat-type output toward the circumference to form a 3D curved part in a shape corresponding to the fixture, wherein the flat-type output is formed in the circumferential direction on the workbench of the 3D printer While having a closed shape along with a tensile residual stress in the circumferential direction and a compressive residual stress in the radial direction, the curved molded article is, while receiving the heat from the heat supply device, the fixture according to the time of heat conduction It is characterized in that it is formed by simultaneously and uniformly bending the flat output in a radial direction.

The planar printout consists of at least one annular layer on the workbench of the 3D printer, with a void space in the inner area of the respective annular layer, towards the outer area from the inner area of the respective annular layer towards the heating nozzle output through Having an anisotropically printed plate of a predetermined width formed by setting a printing path to be output in a circle while drawing concentric circles in multiple layers using a plastic line, the printing starting point located in the inner diameter of the individual annular layer and the above It may have a line transition region helically connecting the individual ply of the plastic line between printing endpoints located on the outer diameter of the individual annular layers.

The curved molded article is based on a planar output comprising at least one annular layer and having an anisotropic output plate in each annular layer, while transferring the heat of the heat supply device to the planar output, an anisotropic output in the planar output The tensile residual stress is relaxed along the circumferential direction of the plate, and along with the contraction, the compressive residual stress is relaxed along the radial direction of the anisotropic output plate in the planar output to cause expansion, so that it is relatively in the outer diameter compared to the inner diameter of the flat output. It may be formed by making the outer diameter side relative to the inner diameter side rise relatively obliquely toward the fixture in the planar output by a larger strain difference.

The flat output is composed of lower annular layers sequentially stacked on the workbench of the 3D printer, functional thin film material, and upper annular layers, together with an empty space in the inner region of each lower or upper annular layer, An anisotropic output plate of a predetermined width formed by setting a printing path to output in a circular shape while drawing concentric circles in multiple layers using a plastic line output through the heating nozzle from the inner region of the lower or upper annular layer toward the outer region a line transition region helically connecting the individual ply of plastic line between a printing start point located at the inner diameter of the respective lower or upper annular layer and a printing end point located at the outer diameter of the respective lower or upper annular layer, The uppermost layer of the lower annular layers and the lowermost layer of the upper annular layers are in contact through the functional thin film material, and the thickness of the functional thin film material is smaller than the thickness of the individual annular layers; The line transition region of the respective lower annular layer may be located directly above the line transition region of the respective upper annular layer or spaced apart from the line transition region of the respective upper annular layer.

The curved molded article is made of sequentially stacked lower annular layers, a functional thin film material, and an upper annular layer. During the transfer of the heat of, the tensile residual stress is relaxed along the circumferential direction of the anisotropic output plate in the planar output, and with contraction, the compressive residual stress is relaxed along the radial direction of the anisotropic output plate in the planar output. It may be formed by causing expansion, and causing the outer diameter side relative to the inner diameter side to rise relatively obliquely toward the fixture in the planar output object by a relatively larger difference in strain in the outer diameter compared to the inner diameter of the flat output object.

The flat printout is made of a plurality of polygonal round annular layers on the workbench of the 3D printer, along with an empty space in the inner region of each polygonal round annular layer, along the individual polygonal round annular layers, and arcs at each corner ( An anisotropic output plate in the shape of arc, and an isotropic output plate in a rectangular shape between two corners, the individual polygonal output plate using a plastic line output from the anisotropic output plate through the heating nozzle The plastic line is horizontally wound in multiple layers to print a plurality of arcs concentrically for each round annular layer, and the plastic line is used in the isotropic output plate to repeatedly have a diagonal that intersects layer by layer for every two polygonal round annular layers , The first line transition regions positioned on both sides of the anisotropic output plate may be in contact along the second line transition regions positioned on both sides of the isotropic output plate.

The curved molded article is composed of a plurality of polygonal round annular layers, and in each polygonal round annular layer, an arc-shaped anisotropic output plate for each corner and a square-shaped isotropic output plate for each two edges. Based on the flat output, During the transfer of the heat of the heat supply device to the output, the tensile residual stress is relaxed along the circumferential direction of the anisotropic output plate in the flat-type output and is contracted, and compressed along the radial direction of the anisotropic output in the flat-type output. Residual stress is relaxed to cause expansion, and by a relatively larger difference in strain in the outer diameter compared to the inner diameter of the anisotropic output plate, the planar output can be formed by making the outer diameter side relative to the inner diameter side rise relatively obliquely toward the fixture. .

The planar output is composed of annular layers on the workbench of the 3D printer, and a plurality of connecting layers sequentially stacked in the inner region of the annular layers, having a connecting portion dividing the inner region of the annular layers, In the annular layer, an annularly and anisotropically printed plate of a predetermined width is formed by setting the printing path to be output in a circular shape while drawing concentric circles in several layers using the plastic line output through the heating nozzle. , arranging a first straight long line horizontally in multiple layers along one direction, in one of the two connecting layers, in every two connecting layers to form the connecting portion in the inner region of the annular layers, In the other of the two connection layers, a perpendicularly and anisotropically printed plate in which second straight long lines are horizontally arranged in multiple layers along the other direction orthogonal to the one direction, the anisotropic output plate a first line transition region of the orthogonal anisotropic output plate is in contact with or not in contact with a second line transition region of the orthogonal anisotropic output plate, and the connecting portion is formed at least one in the inner region of the annular layers, and in the inner region of the annular layers. When formed in two or more, it is possible to radially connect the inner region of the annular layers.

The curved molded article includes annular layers, and at least one formed in an inner region of the annular layers, dividing the inner region of the annular layers, and a connecting portion having a plurality of connecting layers, so that an annular anisotropic output plate and two Tensile residual stress and compression along the circumferential and radial directions of the annular anisotropic output plate while transferring the heat of the heat supply device to the planar output based on the planar output having an orthogonal anisotropic output plate for each of the connecting layers Residual stress is respectively relaxed to contract and expand, and along the longitudinal and width directions of the orthogonal anisotropic output plate are tensile residual stress and compressive residual stress, or compressive residual stress and tensile residual stress are respectively relaxed to contract and expand or expand and causing shrinkage, by the difference in strain in the inner and outer diameters of the annular anisotropic output plate and in the longitudinal direction and the width direction of the orthogonal anisotropic output plate, in the annular anisotropic output plate toward the fixture, the inner diameter side versus the outer diameter side It may be formed by making a relatively incline soar, and increasing the peripheral area compared to the central area in the orthogonal anisotropic output plate when viewed along the bending direction of the annular layers.

The flat output is made of annular layers on the workbench of the 3D printer, and circular layers that shield the inner region of the annular layers, and is output through the heating nozzle in an individual annular layer To form the circular layers in the inner region of the annular layers, having an annular anisotropic output plate of a predetermined width formed by setting a printing path to be output in a circle while drawing concentric circles in multiple layers using a plastic line, In the individual circular layer, having an isotropically printed plate that is crossed layer by layer every two circular layers using the plastic line, the first line transition region of the annular anisotropic output plate is the second of the isotropic output plate Two lines may be in contact with the transition region.

The curved molded article is composed of annular layers and circular layers that shield the inner region of the annular layers, and an annular anisotropic output plate in individual annular layers and an isotropic output plate that intersects layer by layer for each two circular layers Based on a planar output As a result, while transferring the heat of the heat supply device to the planar output, the tensile residual stress and the compressive residual stress are respectively relaxed along the circumferential and radial directions of the annular anisotropic output plate to cause contraction and expansion, Due to the larger strain difference in the outer diameter versus the inner diameter of the annular anisotropic output plate, the outer diameter side versus the inner diameter side rises relatively obliquely toward the fixture in the annular anisotropic output plate, and when viewed from the circular layers, the annular layer compared to the annular layer It can be formed to be relatively flat in circular layers.

The flat output is made of a lower annular pad sequentially stacked on the workbench of the 3D printer, a metal conductive wire part, and an upper annular pad using a plastic line output through the heating nozzle. The inner and outer parts of the annular body in the metal lead part with the intaglio groove for receiving the annular body of the metal lead part in the lower annular pad, having the lower annular pad and the upper annular pad for inserting the metal lead part a plurality of terminal receiving grooves each receiving a plurality of rectangular terminals projecting radially toward Both ends of the individual rectangular terminals are exposed, and the lower annular pad and the upper annular pad may have a tensile residual stress along a circumferential direction and a compressive residual stress along a radial direction in annular anisotropy.

In the curved molded article, the tensile residual stress and the compressive residual stress are respectively relaxed and contracted along the circumferential and radial directions of the lower or upper annular pad while transferring the heat of the heat supply device to the planar output. causing expansion, causing the lower or upper annular pad to swell relatively obliquely toward the fixture in the lower or upper annular pad by a greater strain difference in the outer diameter versus the inner diameter of the lower or upper annular pad, wherein the metal lead part may be formed to be bent along a curve between the lower annular pad and the upper annular pad.

The method for manufacturing a curved molded article using the 4D printing technology according to the present invention is a material extrusion method using a plastic line in a 3D printer to form a 2.5D planar part in a closed curve shape on a workbench. After that, insert the planar output from the workbench into the heat supply device to position the fixture of the heat supply in the central area of the flat output, while transferring the heat of the heat supply to the flat output, place the flat output around the fixture Consistency, reproducibility, and uniformity of the shape of a curved molded product made by bending a flat output through the heating effect of the heat supply device and shape constraint of the fixture as it induces deformation that is bent toward can be given

1 to 3 are schematic diagrams illustrating a conventional material extrusion type 3D printing technology and a 4D printing technology using the same.

4 to 7, and 17 and 18 are schematic views illustrating a method of manufacturing a curved molded article using the 4D printing technology according to the first embodiment of the present invention.

8 to 12 are schematic views illustrating a method of manufacturing a curved molded article using 4D printing technology according to a second embodiment of the present invention.

13 is a schematic diagram illustrating a method of manufacturing a curved molded article using 4D printing technology according to a third embodiment of the present invention.

14 is a schematic diagram illustrating a method of manufacturing a curved molded article using 4D printing technology according to a fourth embodiment of the present invention.

15 is a schematic diagram illustrating a method of manufacturing a curved molded article using 4D printing technology according to a fifth embodiment of the present invention.

16 is a schematic diagram illustrating a method of manufacturing a curved molded article using 4D printing technology according to a sixth embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those of ordinary skill in the art can easily practice the present invention.

4 to 7, and 17 and 18 are schematic views illustrating a method of manufacturing a curved molded article using the 4D printing technology according to the first embodiment of the present invention. In this case, the material extrusion type 3D printer outputs a three-dimensional shape, but in order to clearly describe the 4D printing technology, below, the term '2.5D (2.5-dimensional) planar type' refers to the dimension and flatness before applying heat to the three-dimensional shape, and the term '3D curved type' refers to the dimension and flatness after applying heat to the three-dimensional shape. refers to the degree of deformation.

4 to 7, and 17 and 18, the method for manufacturing a curved molded article using the 4D printing technology according to the first embodiment of the present invention is a material extrusion type 3D printer ( In 60 of FIG. 1, using a heating nozzle 20, a printing path is set in the circumferential direction on the workbench 10 of the 3D printer 60 as shown in FIG. part; 120, hereinafter referred to as 'planar output') includes forming as shown in FIG. 5 .

The planar output 120 consists of at least one annular layer on the workbench 10 of the 3D printer 60, with an empty space in the inner region of the individual annular layer, from the inner region to the outer region of the individual annular layer. An anisotropically printed plate of a predetermined width formed by setting the printing path to be output in a circular shape while drawing concentric circles in multiple layers using the plastic line 114 output from the heating nozzle 20 of FIG. 4 toward ; 118) as shown in FIG. 5, helically connecting the individual plies of plastic line 114 between the printing start point T1 located on the inner diameter of the individual annular layer and the printing end point T2 located on the outer diameter of the individual annular layer. It has a line transition region (S1) as shown in FIG.

The printing start point T1 and the printing end point T2 are opposite to each other in the line transition region S1 as shown in FIG. 5 . The line transition region S1 is, as shown in FIG. 5 , an nth plastic line 114 and an n+1th plastic line 114 between the printing start point T1 and the printing end point T2 (however, n is a positive integer) and has a diagonal line repeatedly. The flat output 120 has a tensile residual stress in a circumferential direction and a compressive residual stress in a radial direction while having the closed shape of FIG. 5 along the circumferential direction on the workbench 10 of the 3D printer 60 .

Because the heating nozzle 20 tensions the high-temperature plastic line 114 along the printing length or circumferential direction through the opening and perpendicular to the printing length (or circumferential) direction, for example, the high-temperature plastic in the radial direction. This is because, while compressing the line 114 , a high-temperature plastic line 114 is exposed on the workbench 10 of the 3D printer 60 to generate a residual stress in the plastic line 114 .

Next, in the manufacturing method of the curved molded article using the 4D printing technology, as shown in FIG. 6 , the flat output 120 is positioned inside the heat supply device 145 using the heat supply device 145 , It is provided in the supply device 145 and includes positioning the fixture 140 corresponding to the curved shape on the flat output 120 . Here, the heat supply device 145 includes an electric oven.

The fixture 140 may be positioned in a chamber (not shown) of the heat supply device 145 to be positioned inside the planar output 120 . The fixture 140 has an inclined surface to correspond to a 4D printing deformable shape.

Thereafter, in the method of manufacturing a curved molded article using the 4D printing technology, when considering FIGS. 6 and 7 , the temperature of the heat supply device 145 is maintained above the thermal deformation temperature of the flat output 120 . In , while transferring heat from the heat supply device 145 to the flat output 120 , bending deformation of the flat output 120 toward the fixture 140 is induced to form a 3D curved shape into a shape corresponding to the fixture 140 . It includes forming a molded part (curved part 130, hereinafter referred to as a 'curved molded article').

The curved molded article 130, when considering FIGS. 6 and 7, while receiving heat from the heat supply device 145, the flat output 120 toward the fixture 140 according to the time of heat transfer is formed by simultaneously and uniformly bending radially. In more detail, when considering FIGS. 17A and 17B in conjunction with FIG. 5 , on the workbench 10 using the nozzle 20 of the 3D printer 60 , the flat-type output 120 is quadrant. A test planar output 100 corresponding to the work of may be produced.

Here, the test planar output 100 has at least one test anisotropic output plate 98 . The test anisotropic output plate 98 is formed by horizontally winding the plastic line 94 in multiple layers so as to print a plurality of arcs concentrically using the plastic line 94 . The test anisotropic output plate 98 has a line transition region S11 on the left and right sides, and a printing start point T11 and a printing end point T12 in the right line transition region S11 of the test anisotropic output plate 98. has

Therefore, the test anisotropic output plate 98, unlike the anisotropic output plate 118 of FIG. 5, does not have a closed shape. In order to understand the 4D printing technology applied to the test planar output 100, the outer diameter of the test anisotropic output plate 98 is fixed to 60 mm, and the width w of the test anisotropic output plate 98 is set to 10 mm, 20 mm, 30 mm, 40 mm, and 50 mm, the test planar output 100 can be prepared in plurality, as shown in FIG. 17A .

The plurality of test planar outputs 100 may be inserted into a heat supply device (not shown in the drawing). The heat supply does not have the fixture of FIG. 5 in the chamber. While the plurality of test planar outputs 100 receive heat from the heat supply device, the difference in strain rates between the inner and outer diameters of the plurality of test planar outputs 100 is, when considering FIGS. 17A and 18 , the test anisotropy As the width w of the output plate 98 increases, it appears gradually larger.

17A and 17B, since the test anisotropic output plate 98 does not have a closed shape like the anisotropic output plate 118 of FIG. It only contracts and expands in a two-dimensional plane even when it receives heat from it. That is, the plurality of test planar outputs 100 cause a difference in strain rate between the inner diameter and the outer diameter by inducing contraction and radial expansion in the circumferential direction while receiving heat from the heat supply device, more specifically, the strain rate of the inner diameter Each of the plurality of non-bending molded articles 105 is deformed due to a difference in strain (shrinkage) of the outer diameter greater than (shrinkage).

However, when considering again FIGS. 5 to 7, the curved molded article 130 is made of at least one annular layer, and based on the planar output 120 having an anisotropic output plate 118 in each annular layer, While the heat of the heat supply device 145 is transferred to the flat-type output 120 , the tensile residual stress is relaxed along the circumferential direction of the anisotropic output plate 118 in the flat-type output 120 , along with the contraction, the flat-type output 120 . ), the compressive residual stress is relaxed along the radial direction of the anisotropic output plate 118 to cause expansion, resulting in a relatively larger strain difference in the outer diameter compared to the inner diameter of the flat output 120 in a predetermined direction in the flat output 120 It is formed so that the outer diameter side relative to the inner diameter side toward the fixture 140 along (R1) rises relatively obliquely.

Because the flat output 120 has a closed shape, the flat output 120 receives heat from the heat supply device 145 while receiving heat from the flat output 120 due to a difference in strain between the inner and outer diameters. This is because the internal stress cannot be radiated to the outside, and the internal stress is used as a self-transformation in the three-dimensional space. Accordingly, the curved molded article 130 is consistent and reproducible with respect to the shape of the curved molded article 130 through the thermal restraint of the heat supply device 145 for the flat output 120 and the molding restraint of the fixture 140 . and is made with uniformity. On the other hand, the line transition region S1 of the planar output 120 remains as a trace on the surface of the curved molded article 130 as shown in FIG. 7 .

In this case, FIG. 12A is a planarly enlarged image of the curved molded article of FIG. 11 , FIG. 12B is an enlarged image of Region A in FIG. 12A , and FIG. 12C is an enlarged image of Region B in FIG. 12A , FIG. 12d is an image showing a cross section of the curved molded article taken along the cutting line I-I' in FIG. 12A .

8 to 12 , a method of manufacturing a curved molded article using 4D printing technology according to a second embodiment of the present invention is disclosed similarly to FIGS. 4 to 7 , but the flat output of FIGS. 8 to 12 . 180 and the curved molded product 190 are structurally different from the flat output 120 and the curved molded product 130 of FIGS. 4 to 7 .

That is, the flat output 180 includes the lower annular layers (140 in FIG. 8 or 9) and functional thin film materials sequentially stacked on the workbench (10 in FIG. 9) of the 3D printer (60 in FIG. 1) An individual lower or upper annular layer consisting of 160 of FIG. 8 or 9 ) and upper annular layers 170 of FIG. 8 or 9 , with an empty space in the inner region of the respective lower or upper

annular layer

140 or 170 , respectively. Set the printing path so that it is output in a circle while drawing concentric circles in multiple layers using the plastic line 114 output through the heating nozzle (20 in FIG. 4) from the inner region of the

layer

140 or 170 toward the outer region Having an anisotropic output plate of a predetermined width (see 118 in Fig. 5) formed, the printing starting point (T1 in Fig. 5) located on the inner diameter of the respective lower or upper

annular layer

140 or 170 and the respective lower or upper annular layer ( 140 or 170 has a line transition region (S2 or S3 in FIG. 11) that spirals the individual ply of plastic line 114 between the printing endpoints (T2 in FIG. 5) located at an outer diameter of 140 or 170).

Here, when considering FIGS. 12C and 12D , the uppermost layer of the lower annular layers 140 and the lowermost layer of the upper annular layers 170 are in contact through the functional thin film material 160 , and the functional thin film The thickness of the material is less than the thickness of the individual

annular layers

160 or 170 . Further, the line transition region S2 of the respective lower annular layer 140 is located directly above the line transition region S3 of the respective upper annular layer 170 or the line transition region S3 of the respective upper annular layer 170 . can be separated from The functional thin film material 160 includes a porous filter fabric having a plurality of meshes 155 as shown in FIG. 8 or 11 or 12B. Meanwhile, the flat output 180 is transformed into a curved molded product 190 by applying the 4D printing technology of FIG. 6 .

Specifically, the curved molded article 190 is, as shown in FIGS. 8 and 9 , sequentially stacked lower annular layers 140 , a functional thin film material 160 , and upper annular layers 170 . Based on the planar output 180 having an anisotropic output plate 118 in its respective lower or upper

annular layer

140 or 170, while transferring the heat of the heat supply device (FIG. 6 145) to the planar output 180 , in the flat output 180 , the tensile residual stress is relaxed along the circumferential direction of the anisotropic output plate 118 to contract, and in the flat output 180 , the compressive residual stress is relaxed along the radial direction of the anisotropic output plate 118 . to cause expansion, so that the outer diameter side relative to the inner diameter side rises relatively obliquely toward the fixture along the predetermined direction R2 in the planar output 180 by a relatively larger difference in strain in the outer diameter compared to the inner diameter of the flat output 180 is formed by

Here, the curved molded article 190 is a circular printing path 175 along between the plastic lines 114 at the surface of the respective lower or upper

annular layer

140 or 170, when considering FIGS. 12B and 12D. ) has In addition, the curved molded article 190 connects the lower annular layer 140 and the upper annular layer 170 through the functional thin film material 160 in consideration of FIGS. 12C and 12D .

Referring to FIG. 13 , a method of manufacturing a curved molded article using 4D printing technology according to a third embodiment of the present invention is disclosed similarly to FIGS. 4 to 7 , but the flat output 210 and the curved shape of FIG. 13 . The molded article 220 is structurally different from the planar output 120 and the curved molded article 130 of FIGS. 4 to 7 .

That is, the flat-type output 210 is made of a plurality of polygonal round annular layers on the workbench 10 of the 3D printer (60 in FIG. 1 ), and with empty space in the inner region of the individual polygonal round annular layers, Along the polygonal round annular layer, an anisotropic output plate 204 in an arc shape at each corner and an isotropic output plate 208 in a rectangular shape between two edges are provided, as shown in FIG. 17B . As shown, using the plastic line 114 output from the anisotropic output plate 204 through the heating nozzle (20 in Fig. 4) to print a plurality of arcs concentrically for each individual polygonal round annular layer 114 ) is wound horizontally in several layers, and the plastic line 114 is used in the isotropic output plate 208 to repeatedly have diagonal lines intersecting each layer for each of the two polygonal round annular layers.

Here, the first line transition region (see S11 in FIG. 17B ) positioned on both sides of the anisotropic output plate 204 is a second line transition region positioned on both sides of the isotropic output plate 208 (not shown in the drawing). city) to contact The isotropic output plate 208 is used to remove in-plane anisotropy in the material extrusion type 3D printer 60 . Meanwhile, the flat output 210 is transformed into a curved molded article 220 by applying the 4D printing technology of FIG. 6 .

Specifically, the curved molded article 220 is composed of a plurality of polygonal round annular layers, and an arc-shaped anisotropic output plate 204 for each corner in each polygonal round annular layer and a square-shaped isotropic output plate for every two corners. Based on the planar output 210 having 208 , the circumference of the anisotropic output plate 204 in the planar output 210 while transferring the heat of the heat supply 145 in FIG. 6 to the planar output 210 . Along with the contraction of the tensile residual stress along the direction, the compressive residual stress is relaxed along the radial direction of the anisotropic output plate 204 in the planar output 210 to cause expansion, compared to the inner diameter of the anisotropic output plate 204 It is formed by making the outer diameter side relative to the inner diameter side rise relatively obliquely toward the fixture (140 in FIG. 6 ) in the planar output 210 due to a relatively larger strain difference in the outer diameter.

Here, since the isotropic output plate 208 does not have in-plane anisotropy, the isotropic output plate 208 continues to maintain its initial shape while transferring the heat of the heat supply device 145 to the planar output 210 . do.

Referring to FIG. 14 , a method for manufacturing a curved molded article using 4D printing technology according to a fourth embodiment of the present invention is disclosed similarly to FIGS. 4 to 7 , but the flat output 240 and the curved shape of FIG. 14 . The molded article 250 is structurally different from the flat molded article 120 and the curved molded article 130 of FIGS. 4 to 7 .

That is, the flat output 240 is annular layers on the workbench 10 of the 3D printer (60 in FIG. 1), and a plurality of connecting layers (not shown in the drawing) sequentially stacked in the inner region of the annular layers. Using a plastic line 114 output through a heating nozzle (20 in FIG. 4 ) in the individual annular layer, with a connection ( 239 in FIG. 14a or 14b or 14c ) that divides the inner region of the annular layers by using to have an annularly and anisotropically printed plate 234 of a predetermined width formed by setting the printing path to be output in a circular shape while drawing concentric circles in multiple layers, and forming a connection part 239 in the inner region of the annular layers In order to do this, in one of the two connecting layers, a first straight long line (not shown in the drawing) is horizontally arranged in multiple layers along one direction, and in the other of the two connecting layers, one It has a perpendicularly and anisotropically printed plate 238 in which second straight long lines (not shown in the drawing) are horizontally arranged in multiple layers along another direction orthogonal to the direction.

Here, the first line transition region (see S1 of FIG. 5 ) of the annular anisotropic output plate 234 may be in contact or non-contact with the second line transition region (not shown in the drawing) of the orthogonal anisotropic output plate 238 . there is. At least one connection portion 239 is formed in the inner region of the annular layers as shown in FIG. 14A or 14B or 14C, and two or more are formed in the inner region of the annular layers as shown in FIG. 14B or 14C. When formed, annular It radially connects the inner region of the layers.

The orthogonal anisotropic output plate 238 has a tensile residual stress along the longitudinal direction and a compressive residual stress along the width direction in one of the two connecting layers for every two connecting layers, and in the other of the two connecting layers, It has a compressive residual stress along the longitudinal direction and a tensile residual stress along the width direction. Meanwhile, the flat output 240 is transformed into a curved molded article 250 by applying the 4D printing technology of FIG. 6 .

Specifically, the curved molded article 250 includes annular layers, and at least one formed in the inner region of the annular layers, dividing the inner region of the annular layers, and a connecting portion 239 having a plurality of connecting layers. Based on a planar output 240 having an annular anisotropic output plate 234 in individual annular layers and an orthogonal anisotropic output plate 238 per two connecting layers, the planar output 240 is supplied with the heat supply device 145 of FIG. During the heat transfer of the annular anisotropic output plate 234 along the circumferential and radial directions, the tensile residual stress and the compressive residual stress are respectively relaxed and contracted and expanded together with the longitudinal direction of the orthogonal anisotropic output plate 238 and Tensile residual stress and compressive residual stress or compressive residual stress and tensile residual stress are respectively relaxed to cause contraction and expansion or expansion and contraction along the width direction, so that at the inner diameter and outer diameter of the annular anisotropic output plate 234 and orthogonal anisotropy output Due to the difference in strain in the longitudinal direction and the width direction of the plate 238, the outer diameter side relative to the inner diameter side toward the fixture (140 in FIG. 6) in the annular anisotropic output plate 234 rises relatively obliquely, and the annular layers are bent When viewed along the direction, the orthogonal anisotropy output plate 238 is formed to have a higher peripheral area compared to the central area.

Here, while the orthogonal anisotropic output plate 238 transfers the heat of the heat supply device 145 to the planar output 240 , as described in FIG. 3 , bending deformation occurs, similarly to the movement of the starfish see.

Referring to FIG. 15 , a method for manufacturing a curved molded article using 4D printing technology according to a fifth embodiment of the present invention is similarly disclosed in FIGS. 4 to 7 , but the flat output 270 and the curved shape of FIG. 15 . The molded article 280 is structurally different from the flat molded article 120 and the curved molded article 130 of FIGS. 4 to 7 .

That is, the planar output 270 consists of annular layers on the workbench 10 of the 3D printer (60 in FIG. 1) and circular layers that shield the inner region of the annular layers, and in individual annular layers, a heating nozzle It has an annular anisotropic output plate 264 of a predetermined width formed by setting a printing path to be output in a circular shape while drawing concentric circles in multiple layers using the plastic line 114 output through (20 in FIG. 4), To form the circular layers in the inner region of the annular layers, in each circular layer, an isotropically printed plate 268 is crossed layer by layer for every two circular layers using a plastic line 1140 .

Here, the first line transition region (see S1 of FIG. 5 ) of the annular anisotropic output plate 264 is in contact with a second line transition region (not shown) of the isotropic output plate 268 . The isotropic output plate 268 is used to remove the in-plane anisotropy, as described in FIG. 13 . Meanwhile, the flat output 270 is transformed into a curved molded article 280 by applying the 4D printing technology of FIG. 6 .

Specifically, the curved molded article 280 is composed of annular layers and circular layers for shielding the inner region of the annular layers, so that the annular anisotropic output plate 264 and the two circular layers are intersected layer by layer in individual annular layers Based on the planar output 270 having the isotropic output plate 268, while transferring the heat of the heat supply device 145 of FIG. 6 to the planar output 270, the circumferential direction of the annular anisotropic output plate 264 and In the radial direction, the tensile residual stress and the compressive residual stress are respectively relaxed to cause contraction and expansion, so that by a larger strain difference in the outer diameter compared to the inner diameter of the annular anisotropic output plate 264, the annular anisotropic output plate 264 also 6, the outer diameter side relative to the inner diameter side rises relatively obliquely toward the fixture 140, and when viewed from the circular layers, it is formed relatively flat in the circular layers compared to the annular layers.

Referring to FIG. 16 , a method for manufacturing a curved molded article using 4D printing technology according to a sixth embodiment of the present invention is similarly disclosed in FIGS. 4 to 7 , but the flat output 340 and the curved shape of FIG. 16 . The molded article (not shown in the drawing) is structurally different from the flat output 120 and the curved molded article 130 of FIGS. 4 to 7 .

The flat output 340 includes a lower annular pad 300, a metal wire part 320, and an upper annular pad 330 sequentially stacked on the workbench 10 of the 3D printer (60 in FIG. 1). ), while having a lower annular pad 300 and an upper annular pad 330 for inserting the metal conductive wire 320 using the plastic line 114 output through the heating nozzle 20, the lower In the annular pad 300 , the metal lead 320 with a recess 294 for receiving the annular body 314 of the metal lead 320 radially protrudes from the metal lead 320 toward the inside and outside of the annular body 314 . having a plurality of terminal accommodating grooves 298 for accommodating a plurality of square terminals 318, respectively, and in the lower annular pad 300 and the upper annular pad 330, the individual square terminals 318 together with the annular body 314 ), and exposes both ends of the individual square terminals 318 .

Here, the lower annular pad 300 and the upper annular pad 330 may have a tensile residual stress along a circumferential direction and a compressive residual stress along a radial direction in annular anisotropy. Meanwhile, the flat output 340 is transformed into a curved molded article by applying the 4D printing technology of FIG. 6 .

Specifically, the curved molded article is based on a flat output 340 comprising a lower annular pad 300, a metal conductive wire part 320, and an upper annular pad 330 stacked sequentially, a flat output 340 6, the tensile residual stress and the compressive residual stress along the circumferential and radial directions of the lower or upper

annular pad

300 or 330 are respectively relaxed during heat transfer of the heat supply device 145 of FIG. As a result, by a larger strain difference in the outer diameter versus the inner diameter of the lower or upper

annular pad

300 or 330 , the outer diameter side versus the inner diameter side towards the fixture 140 of FIG. 6 in the lower or upper

annular pad

300 or 330 . to rise relatively obliquely, and is formed to be bent along the curvature between the lower annular pad 300 and the upper annular pad 330 in the metal conductive wire part 320 .

Here, the curved molded article connects the lower annular pad 300 and the upper annular pad 330 around the metal conductive wire 320 while transferring the heat of the heat supplying device 140 to the flat output 340 . is formed by Accordingly, the metal conductive wire portion 320 is fixed to the lower annular pad 300 and the upper annular pad 330 . The curved molded article may be used as an electrode matched to a peripheral shape in a wearable device.

Claims

In a material extrusion type 3D printer, using a heating nozzle, a printing path is set in the circumferential direction on the workbench of the 3D printer to form a 2.5D planar part of a closed curve shape, and ,

Using a heat supply device to position the flat-type output inside the heat-supply device, a fixture provided in the heat-supply device and corresponding to a curved shape is positioned on the flat-type output,

In a state where the temperature of the heat supply device is maintained above the thermal deformation temperature of the planar output, bending deformation of the flat output is caused toward the fixture while heat is transferred from the heat supply to the flat output Including forming a 3D curved molded part (curved part) in a shape corresponding to the fixture,

The flat output is

Has a tensile residual stress in the circumferential direction and a compressive residual stress in a radial direction while having a closed shape along the circumferential direction on the workbench of the 3D printer,

The curved molded article is

A method of manufacturing a curved molded article using 4D printing technology, wherein while receiving the heat from the heat supply device, the flat output is simultaneously and uniformly bent radially toward the fixture according to a time of heat conduction.
According to claim 1,

The flat output is

consisting of at least one annular layer on the workbench of the 3D printer,

A printing path so that it is output in a circular fashion while drawing concentric circles in multiple layers using a plastic line output through the heating nozzle from the inner region to the outer region of the individual annular layer, with an empty space in the inner region of the individual annular layer Having an anisotropically printed plate of a predetermined width formed by setting

4D printing technology, having a line transition region helically connecting the individual ply of plastic line between a printing start point located on the inner diameter of the individual annular layer and a printing end point located on the outer diameter of the individual annular layer. A method for manufacturing the used curved molded product.
According to claim 1,

The curved molded article is

Based on a planar output comprising at least one annular layer and having an anisotropic output plate in each annular layer,

While transferring the heat of the heat supply device to the planar output, the tensile residual stress is relaxed along the circumferential direction of the anisotropic output plate in the planar output to contract and, in the flat output, the radial direction of the anisotropic output plate Accordingly, the compressive residual stress is relaxed to cause expansion, and by a relatively larger difference in strain in the outer diameter compared to the inner diameter of the flat-type output, the outer diameter side relative to the inner diameter side is relatively inclined toward the fixture in the flat-type output. A method of manufacturing a curved molded product using 4D printing technology.
According to claim 1,

The flat output is

With the lower annular layers sequentially stacked on the workbench of the 3D printer, the functional thin film material, and the upper annular layers,

Drawing concentric circles in multiple layers using a plastic line output through the heating nozzle from the inner region of the individual lower or upper annular layer towards the outer region, together with an empty space in the inner region of the individual lower or upper annular layer Having an anisotropic output plate of a predetermined width formed by setting a printing path to be output in a circular shape,

a line transition region helically connecting the individual ply of plastic line between a printing start point located on the inner diameter of the respective lower or upper annular layer and a printing end point located on the outer diameter of the respective lower or upper annular layer;

The uppermost layer of the lower annular layers and the lowermost layer of the upper annular layers,

In contact through the functional thin film material,

The thickness of the functional thin film material is,

smaller than the thickness of the individual annular layers,

The line transition region of the individual lower annular layer is

A method of manufacturing a curved molded article using 4D printing technology, which is located directly above the line transition region of the respective upper annular layer or is spaced from the line transition region of the respective upper annular layer.
According to claim 1,

The curved molded article is

Based on a planar output having an anisotropic output plate in an individual lower or upper annular layer, which is composed of sequentially stacked lower annular layers, a functional thin film material, and an upper annular layer,

While transferring the heat of the heat supply device to the planar output, the tensile residual stress is relaxed along the circumferential direction of the anisotropic output plate in the planar output and contracts, along with the radial direction of the anisotropic output in the flat output The compressive residual stress is relaxed along the , A method for manufacturing a curved molded product using 4D printing technology.
According to claim 1,

The flat output is

As it consists of a plurality of polygonal round annular layers on the workbench of the 3D printer,

Along the individual polygonal round annular layer, along with the empty space in the inner region of each polygonal round annular layer, an anisotropic output plate with an arc shape at each edge, and a rectangular shape between two edges has an isotropic output plate of

Horizontally winding the plastic line output through the heating nozzle in multiple layers to print a plurality of arcs concentrically for each individual polygonal round annular layer using a plastic line in the anisotropic output plate,

In the isotropic output plate, using the plastic line, repeatedly having a diagonal that intersects layer by layer for every two polygonal round annular layers,

The first line transition regions located on both sides of the anisotropic output plate,

A method of manufacturing a curved molded article using 4D printing technology, in contact along a second line transition region located on both sides of the isotropic output plate.
According to claim 1,

The curved molded article is

Based on a planar output having an arc-shaped anisotropic output plate at each corner and a square-shaped isotropic output plate between two corners in individual polygonal round annular layers,

While transferring the heat of the heat supply device to the planar output, the tensile residual stress is relaxed along the circumferential direction of the anisotropic output plate in the planar output to contract and, in the flat output, the radial direction of the anisotropic output plate Accordingly, the compressive residual stress is relaxed to cause expansion, and by a relatively larger difference in strain in the outer diameter compared to the inner diameter of the anisotropic output plate, the planar output is formed by making the outer diameter side relative to the inner diameter side rise relatively obliquely toward the fixture , A method for manufacturing a curved molded product using 4D printing technology.
According to claim 1,

The flat output is

Having an annular layer on the workbench of the 3D printer and a connecting portion that divides the inner region of the annular layers by consisting of a plurality of connecting layers sequentially stacked in the inner region of the annular layers,

In each annular layer, an annularly and anisotropically printed plate of a predetermined width is formed by setting the printing path so that it is output in a circular shape while drawing concentric circles in multiple layers using the plastic line output through the heating nozzle. have,

In order to form the connecting portion in the inner region of the annular layers, for every two connecting layers, in one of the two connecting layers, horizontally a multiplied first straight long line along one direction is arranged in multiple layers, It has a perpendicularly anisotropically printed plate (perpendicularly and anisotropically printed plate) in which second straight long lines are horizontally arranged in multiple layers along the other direction orthogonal to the one direction in the rest of the connecting layers,

A first line transition region of the annular anisotropic output plate,

in contact or non-contact with the second line transition region of the orthogonal anisotropic output plate;

The connection part,

at least one formed in the inner region of the annular layers;

When two or more are formed in the inner region of the annular layers, radially connecting the inner region of the annular layers, a method for manufacturing a curved molded article using 4D printing technology.
According to claim 1,

The curved molded article is

an annular layer and at least one formed in the inner region of the annular layers, dividing the inner region of the annular layers, and comprising a connecting portion having a plurality of connecting layers to form an annular anisotropic output plate in each annular layer and orthogonal anisotropy per two connecting layers Based on the flat print with the output plate,

While transferring the heat of the heat supply device to the planar output, the tensile residual stress and the compressive residual stress are respectively relaxed along the circumferential and radial directions of the annular anisotropic output plate, together with the contraction and expansion, and the orthogonal anisotropic output Tensile residual stress and compressive residual stress or compressive residual stress and tensile residual stress are respectively relaxed along the longitudinal and width directions of the plate to cause contraction and expansion or expansion and contraction,

At the inner diameter and outer diameter of the annular anisotropic output plate, and by the difference in strain in the longitudinal direction and the width direction of the orthogonal anisotropic output plate, the outer diameter side relative to the inner diameter side toward the fixture in the annular anisotropic output plate rises relatively obliquely And, when viewed along the bending direction of the annular layers, the orthogonal anisotropic output plate is formed by increasing the peripheral area compared to the central area, a method of manufacturing a curved molded article using 4D printing technology.
According to claim 1,

The flat output is

to consist of a lower annular pad sequentially stacked on the workbench of the 3D printer, a metal wire part, and an upper annular pad,

Having the lower annular pad and the upper annular pad for inserting the metal conductive wire using a plastic line output through the heating nozzle,

A plurality of terminal accommodating grooves each receiving a plurality of rectangular terminals projecting radially from the metal lead part toward the inside and the outside of the annular body in the lower annular pad together with an intaglio groove for accommodating the annular body of the metal conductive wire part To have,

In the lower annular pad and the upper annular pad, together with the annular body, the central region of the individual rectangular terminal is covered, and both ends of the individual rectangular terminal are exposed;

the lower annular pad and the upper annular pad,

Annular anisotropy, with tensile residual stress along the circumferential direction and compressive residual stress along the radial direction,

The curved molded article is

During the transfer of the heat of the heat supply device to the planar output, the tensile residual stress and the compressive residual stress are respectively relaxed along the circumferential and radial directions of the lower or upper annular pad to cause contraction and expansion,

Due to the greater strain difference in the outer diameter versus the inner diameter of the lower or upper annular pad, the lower or upper annular pad makes the outer diameter side relative to the inner diameter side rise relatively obliquely toward the fixture, and the lower annular pad in the metal lead part A method of manufacturing a curved molded article using 4D printing technology, which is formed to be bent along the curve between the and the upper annular pad.