Patent Publication Number: US-2021162661-A1

Title: Three-dimensional printing apparatus

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims priority to and the benefit of Korean Patent Application No. 10-2019-0158275, filed on Dec. 2, 2019, the disclosure of which is incorporated herein by reference in its entirety. 
     BACKGROUND 
     1. Field 
     Embodiments of the present disclosure relate to a three-dimensional (3D) printing apparatus. 
     2. Discussion of Related Art 
     A three-dimensional (3D) printing apparatus is an apparatus configured to manufacture a preset 3D shape according to a 3D drawing. Here, such 3D printing apparatuses may be classified, according to materials, into a frequency division multiplex (FDM) method, a poly jet method, and a selective laser sintering (SLS) method. Particularly, the FDM method uses a solid material, the poly jet method uses a liquid material, and the SLS method uses a powder material. 
     Among them, in the FDM method, a plastic material which is a solid may be melted and discharged onto a printing bed so as to perform a printing operation, and the melted plastic material may be gradually stacked on a molding plate so as to manufacture a 3D shape. 
     Meanwhile, in order to output a 3D product formed of a composite material having different colors and properties, it is necessary to alternately use a plurality of types of filaments having different colors and properties. However, in a conventional 3D printing apparatus, there are problems that a plurality of types of filaments are sequentially and alternately inserted into a single nozzle and heater to be used for a printing operation and materials having different properties are mixed with each other during a 3D printing operation. 
     Also, since the plurality of types of filaments have different melting temperatures, heating a heater according to each material property so as to use the heater for the 3D printing operation takes a long time, and finally, this causes degradation of 3D printing output quality is caused. 
     SUMMARY 
     Embodiments of the present disclosure are intended to provide a three-dimensional (3D) printing apparatus capable of performing a 3D printing operation using any one selected from a plurality of nozzle assemblies and capable of performing replacement with any other of the plurality of nozzle assemblies. 
     Embodiments of the present disclosure are also intended to provide a 3D printing apparatus capable of alternately using a variety of materials having different properties according to a user&#39;s needs. 
     Embodiments of the present disclosure are also intended to provide a 3D printing apparatus capable of easily controlling coupling and separation of a nozzle assembly. 
     Embodiments of the present disclosure are also intended to provide a 3D printing apparatus capable of reducing vibrations and a load on a driving portion during separation of a nozzle assembly. 
     Embodiments of the present disclosure are also intended to provide a 3D printing apparatus capable of preventing heat from being generated at a coupled part while coupling of a nozzle assembly is maintained. 
     According to an aspect of the present disclosure, there is a 3D printing apparatus including a housing, a plurality of nozzle assemblies each including a nozzle portion and a heater, a moving grip portion separable from or fastenable to any one of the plurality of nozzle assemblies, a driving portion formed in the housing and configured to move the moving grip portion in at least two axial directions, and a standby frame on which at least one of the plurality of nozzle assemblies is mounted. Here, each of the plurality of nozzle assemblies includes a first coupling portion. The moving grip portion includes a second coupling portion that allows the first coupling portion to be magnetically coupled therewith. Any one of the first coupling portion and the second coupling portion is formed of a magnetic body. Also, the other of the first coupling portion and the second coupling portion is formed of an electromagnet. 
     The moving grip portion may include at least two guide pins formed to protrude toward one side. Here, each of the plurality of nozzle assemblies may include at least two guide grooves into which the guide pins are insertable. Also, the at least two guide pins may be inserted into the at least two guide grooves such that the moving grip portion and the any one of nozzle assemblies may be located to come into contact with each other in a preset structure. 
     The moving grip portion may include a fastening portion rotated by a preset angle. Here, each of the plurality of nozzle assemblies may include a fastened groove into which the fastening portion is inserted. Also, any one of the plurality of nozzle assemblies may be pressed against and fastened to the moving grip portion as the fastening portion is rotated while being inserted into the fastened groove. 
     Each of the plurality of nozzle assemblies may include an attached block including the fastened groove formed therein. Here, the fastened groove may be formed to extend to a certain length. Also, the fastening portion may approach from one side of the attached block, be inserted into and pass through the fastened groove, and be rotated while being inserted into the fastened groove so as to be pressed against the other surface of the attached block. 
     The standby frame may include a plurality of mounting portions on which the plurality of nozzle assemblies are correspondingly mounted. Here, each of the plurality of mounting portions may include a mount-support portion formed to protrude toward an inside of the housing and at least two mounting pins located to be parallel to the ground and vertically spaced apart from each other. The at least two mounting pins may be formed to protrude from the mount-support portion in a direction perpendicular to a protruding direction of the mount-support portion. Each of the plurality of nozzle assemblies may include at least two mounting holes. Also, at least one of the plurality of nozzle assemblies may be mounted on the standby frame while the at least two mounting pins are correspondingly inserted into the at least two mounting holes. 
     The 3D printing apparatus may further include a control portion connected to the driving portion and the moving grip portion and a bed portion on which a product having a preset shape is formed by the nozzle assembly fastened to the moving grip portion. Here, the control portion may sense a distance between the bed portion and the nozzle assembly fastened to the moving grip portion. Also, the nozzle assembly may form the product having the preset shape to compensate for a height error on the basis of the distance. 
     The housing may include four side members located to be perpendicular to the ground. The 3D printing apparatus may include at least two partition members disposed to be spaced at a certain interval apart from at least two of the side members. Here, a partitioned space may be formed between the at least two partition members and the at least two side members. Also, at least a part of the driving portion may be located in the partitioned space. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above and other objects, features and advantages of the present disclosure will become more apparent to those of ordinary skill in the art by describing exemplary embodiments thereof in detail with reference to the accompanying drawings, in which: 
         FIG. 1  is a view of a three-dimensional (3D) printing apparatus according to one embodiment of the present disclosure; 
         FIG. 2  is a view illustrating an inner structure of a housing of the 3D printing apparatus according to one embodiment of the present disclosure; 
         FIG. 3  is an enlarged view illustrating part A of  FIG. 2 ; 
         FIG. 4  is an enlarged view illustrating part B of  FIG. 2 ; 
         FIG. 5  is a view illustrating a standby frame structure of the 3D printing apparatus according to one embodiment of the present disclosure; 
         FIG. 6  is a first exploded perspective view illustrating a moving grip portion and a nozzle assembly of the 3D printing apparatus according to one embodiment of the present disclosure; and 
         FIG. 7  is a second exploded perspective view illustrating the moving grip portion and the nozzle assembly of the 3D printing apparatus according to one embodiment of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS 
     Hereinafter, detailed embodiments of the present disclosure will be described with reference to the accompanying drawings. However, these are merely examples and the present disclosure is not limited thereto. 
     In describing embodiments of the present disclosure, when it is determined that a detailed description of known techniques associated with the present disclosure would unnecessarily obscure the subject matter of the present disclosure, the detailed description thereof will be omitted. Also, terms used herein are defined in consideration of the functions of the present disclosure and may be changed depending on a user, the intent of an operator, or a custom. Accordingly, the terms should be defined based on the following overall description of this specification. 
     The technical concept of the present disclosure will be determined by the claims, and the following embodiments are merely means for efficiently describing the technical concept of the present disclosure to one of ordinary skill in the art. 
       FIG. 1  is a view of a three-dimensional (3D) printing apparatus  10  according to one embodiment of the present disclosure,  FIG. 2  is a view illustrating an inner structure of a housing  100  of the 3D printing apparatus  10  according to one embodiment of the present disclosure,  FIG. 3  is an enlarged view illustrating part A of  FIG. 2 , and  FIG. 4  is an enlarged view illustrating part B of  FIG. 2 . 
     Referring to  FIGS. 1 to 4 , the 3D printing apparatus  10  according to one embodiment of the present disclosure may include the housing  100 , a plurality of nozzle assemblies  200 , a moving grip portion  300 , a driving portion  400 , and a standby frame  500 . Here, each of the plurality of nozzle assemblies  200  may include a nozzle portion  241 , a heater  242 , and an extrusion motor  243  configured to extrude a material toward the nozzle portion  241 . 
     Also, the plurality of nozzle assemblies  200  may be connected to materials having different properties and fastened to the moving grip portion  300  to be used for 3D printing operation. Here, a material connected to each of the plurality of nozzle assemblies  200  may be moved toward the heater  242  by the extrusion motor  243 , and a material melted by the heater  242  may be discharged outward through the nozzle portion  241 . 
     Meanwhile, the above-described moving grip portion  300  may be separated from or fastened to any one of the plurality of nozzle assemblies  200 , and the driving portion  400  may be formed in the housing  100  and move the moving grip portion  300  in at least two axial directions. Also, at least one of the plurality of nozzle assemblies  200  may be mounted and located in the standby frame  500 . That is, the 3D printing apparatus  10  according to one embodiment of the present disclosure may perform the 3D printing operation while alternately selecting a plurality of materials. 
     In detail, the plurality of nozzle assemblies  200  may be located in a state of being mounted on the standby frame  500 , and the moving grip portion  300  may be moved by the driving portion  400  and fastened to any one of the plurality of nozzle assemblies  200 . In this case, other parts excluding the any one of the plurality of nozzle assemblies  200  may be located on the standby frame  500 . Also, the moving grip portion  300  fastened to the any one of nozzle assemblies  200  may be moved by the driving portion  400  in at least two axial directions, and the 3D printing operation may be performed by moving the moving grip portion  300  and operating the any one of the nozzle assemblies  200 . 
     In more detail, each of the plurality of nozzle assemblies  200  may include a first coupling portion  210  (refer to  FIG. 7 ), and the moving grip portion  300  may include a second coupling portion  310  (refer to  FIG. 6 ) capable of being magnetically coupled with the first coupling portion  210 . Here, any one of the first coupling portion  210  and the second coupling portion  310  may be formed of a magnetic material, and the other of the first coupling portion  210  and the second coupling portion  310  may be formed of an electromagnet. Preferably, the second coupling portion  310  included in the moving grip portion  300  may be formed of an electromagnet, and the first coupling portion  210  included in the nozzle assembly  200  may be formed of a magnetic material. 
     That is, the second coupling portion  310  of the moving grip portion  300  may determine whether to generate a magnetic force according to whether a current is applied. When the magnetic force is generated in the second coupling portion  310 , the first coupling portion  210  adjacent thereto may be located to come into contact with the second coupling portion  310  due to the magnetic force. 
     Meanwhile, the 3D printing apparatus  10  according to one embodiment of the present disclosure may further include a control portion  600  connected to the driving portion  400  and the moving grip portion  300  and further include a bed portion  700  on which a product formed by the nozzle assembly  200  fastened to the moving grip portion  300  to have a preset shape is located. Also, the driving portion  400  may include a first shaft  410  configured to guide movement of the moving grip portion  300  in an X-axis direction, a second shaft  420  configured to guide movement of the moving grip portion  300  in a Y-axis direction, and a third shaft  430  configured to guide movement of the bed portion  700  in a Z-axis direction. 
     In addition, the driving portion  400  may include a plurality of motor members configured to move the moving grip portion  300  in the X-axis and Y-axis directions and to move the bed portion  700  in the Z-axis direction. Here, X-axis and Y-axis may be axial directions which are perpendicular to each other in a plane parallel to the ground, and Z-axis may refer to a height direction perpendicular to the ground. Also, the driving portion  400  may control positions of the moving grip portion  300  on the X-axis and Y-axis by driving the moving grip portion  300  in at least one side of the X-axis and Y-axis, and the driving portion  400  may control a height position of the bed portion  700  in the Z-axis direction. 
     Meanwhile, movement of the moving grip portion  300  is not limited thereto, and the driving portion  400  may control the moving grip portion  300  to move in three axial directions such as the X-axis, Y-axis, and Z-axis directions. In addition, the nozzle assembly  200  fastened to the moving grip portion  300  may form a product having a preset shape on the basis of height information preset in the control portion  600 . 
     Meanwhile, the control portion  600  may sense a distance between the bed portion  700  and the any one of the plurality of nozzle assemblies  200  fastened to the moving grip portion  300 . Also, the any one of the plurality of nozzle assemblies  200  may form the product having the preset shape to compensate for a height error on the basis of the sensed distance. 
     In detail, when the height information between the nozzle assembly  200  and the bed portion  700 , which is preset in the control portion  600 , differs from the actually sensed distance between the nozzle assembly  200  and the bed portion  700  during the 3D printing operation using the any one of the plurality of nozzle assemblies  200  fastened to the moving grip portion  300 , the control portion  600  may determine that a height error occurs between the nozzle assembly  200  and the bed portion  700 . 
     That is, a manufacturing error may occur such as being manufactured in a shape different from the preset product shape due to the height error during the 3D printing operation using the nozzle assembly  200 . Here, the control portion  600  may control an extrusion speed and the like of the any one nozzle assembly  200  to compensate for the manufacturing error caused by the height error, and the product formed on the bed portion  700  may be formed to have an initially preset shape. 
     Meanwhile, the housing  100  may include four side members  110  located to be perpendicular to the ground, and the 3D printing apparatus  10  according to one embodiment of the present disclosure may further include at least two partition members (not shown) disposed to be spaced at a certain distance from at least two side members  110 . Here, a partitioned space may be formed between the at least two partition members and the at least two side members  110 , and at least a part of the driving portion  400  may be located in the partitioned space. Also, between the at least two partition members, the bed portion  700  may be located and a manufacturing space in which the 3D printing operation is performed may be formed. 
     Also, a heating portion (not shown) may be located in the manufacturing space and may maintain a temperature in the manufacturing space at a preset temperature or higher. Preferably, the heating portion may heat and maintain the temperature in the manufacturing space at a temperature in a range from 200 to 300° C. 
     Consequently, even when engineering plastic is used as a 3D printing material, the manufacturing space may be maintained at a high temperature and an adhesive property between materials having different properties may be increased. In addition, since a product formed on the bed portion  700  during a printing operation using the nozzle assembly  200  is built, it is possible to prevent an end part (edge part) of a contact surface between the product and the bed portion  700  from rolling up. 
     Meanwhile, the plurality of motor members of the driving portion  400  may be located in the partitioned space. That is, the plurality of motor members configured to drive at least one of the moving grip portion  300  and the bed portion  700  may be located in the partitioned space separated from the manufacturing space and may be separated from a high-temperature environment inside the manufacturing space. Consequently, it is possible to prevent the plurality of motor members from being damaged or degraded in performance due to the high-temperature environment caused by the heating portion. 
       FIG. 5  is a view illustrating a structure of the standby frame  500  of the 3D printing apparatus according to one embodiment of the present disclosure. 
     Referring to  FIG. 5 , the above-described standby frame  500  may include a plurality of mounting portions  510  on which the plurality of nozzle assemblies  200  are correspondingly mounted. Here, the plurality of mounting portions  510  may be formed to protrude from any one sidewall member toward the inside of the housing  100 . Also, each of the plurality of mounting portions  510  includes at least two mounting pins  512  located parallel to the ground and a mount-support portion  511  protruding toward the inside of the housing  100  and spaced vertically from each other. 
     In detail, the at least two mounting pints  512  may be formed to protrude from the mount-support portion  511  in a direction perpendicular to a protruding direction of the mount-support portion  511 , and each of the plurality of nozzle assemblies  200  may include at least two mounting holes  230 . Here, at least one of the plurality of nozzle assemblies  200  may be mounted on the standby frame  500  according to the at least two mounting pins  512  being correspondingly inserted into at least two mounting holes  230  in each nozzle assembly  200 . 
     Here, a direction in which the at least two mounting pins  512  are inserted into the at least two mounting holes  230  may perpendicular to an insertion direction of a fastening portion  330  (refer to  FIG. 6 ) and a fastened groove  222  (refer to  FIG. 7 ) which will be described below. That is, it is possible to prevent the at least two mounting holes  230  from being pushed out from the at least two mounting pins  512  due to an external force generated during a process of fastening or separation between the fastening portion  330  and the fastened groove  222  during a process of separating or fastening the moving grip portion  300  and the nozzle assembly  200  standing by on the any one mounting portion  510 . 
     In addition, materials having mutually different properties may be connected to the plurality of nozzle assemblies  200  disposed on the plurality of mounting portions  510 , and information on the materials connected to the nozzle assemblies  200  located on the plurality of mounting portions  510  may be previously input to the control portion  600 . That is, in the control portion  600 , it has been input which material with a property is connected to which one of the plurality of nozzle assemblies  200  disposed on the plurality of mounting portions  510 . Accordingly, the control portion  600  may fasten the nozzle assembly  200  connected to any one material to the moving grip portion  300  only by recognizing a position of each of the plurality of mounting portions  510  during the 3D printing operation and may use any one selected material in the 3D printing operation. 
     Additionally, the control portion  600  may control a heating temperature of a heater  242  in the fastened nozzle assembly  200  corresponding to a property of the any one selected material. Also, it is possible to control a heating temperature of the heating portion according to the property of the any one selected material. Consequently, the control portion  600  may easily control the heating temperature of the heater  2422  and the heating temperature of the heating portion to be appropriate for the material property simultaneously while at least one of the plurality of nozzle assemblies  200  is alternately used. 
       FIG. 6  is a first exploded perspective view illustrating the moving grip portion  300  and the nozzle assembly  200  of the 3D printing apparatus  10  according to one embodiment of the present disclosure, and  FIG. 7  is a second exploded perspective view illustrating the moving grip portion  300  and the nozzle assembly  200  of the 3D printing apparatus  10  according to one embodiment of the present disclosure. 
     Referring to  FIGS. 6 and 7 , the moving grip portion  300  may include a moving block  340  and at least two guide pins  320  formed to protrude from the moving block  340  toward one side, and each of the plurality of nozzle assemblies  200  may include at least two guide grooves  221  into which the guide pins  320  are insertable. Here, the moving block  340  may be formed to face an attached block  220  of any one of nozzle assembly  200 , which will be described below, and the at least two guide pins  320  are inserted into the at least two guide grooves  221  such that the moving grip portion  300  and any one nozzle assembly  200  may be contact-located in a preset structure. That is, the at least two guide pins  320  and the at least two guide grooves  221  may guide a fastening position between the moving grip portion  300  and the nozzle assembly  200 . 
     Also, the moving grip portion  300  may include the fastening portion  330  rotated by a preset angle, and each of the plurality of nozzle assemblies  200  may include the fastened groove  222  into which the fastening portion  330  is inserted. Here, any one of the plurality of nozzle assemblies  200  may be press-fastened to the moving grip portion  300  as the fastening portion  330  is rotated while being inserted into the fastened groove  222 . 
     That is, one of the nozzle assemblies  200  to be used in a printing operation may be stably fastened to the moving grip portion  300  as the fastening portion  330  is rotated while being inserted into the fastened groove  222 . 
     In detail, each of the plurality of nozzle assemblies  200  may include the attached block  220  including the fastened groove  222  formed therein, and the fastened groove  222  may be formed to extend to a certain length. Here, as the moving grip portion  300  is moved, the fastening portion  330  may approach from one side of the attached block  220 , be inserted into and pass through the fastened groove  222 , and rotated while being inserted into the fastened groove  222  so as to be pressed against the other surface of the attached block  220 . 
     That is, the fastening portion  330  may press-fasten the attached block  220 , and the nozzle assembly  200  may be located to be fastened to the moving grip portion  300  even when a current is not applied to the second coupling portion  310  (that is, an electromagnet is not operated). Consequently, to attach and fasten the moving grip portion  300  to the nozzle assembly  200 , it is unnecessary to continuously apply currents to the second coupling portion  310  and it is possible to alleviate heating and the like caused by continuously applying currents. 
     In more detail, the moving grip portion  300  may further include a rotation operation portion  333  configured to rotate the fastening portion  330 . Also, the fastening portion  330  may include a rotation body  331  formed to have a cylindrical shape with a certain length and extending protrusions  332  formed to protrude from both sides of an end of the rotation body  331  in a radial direction. Here, the rotation body  331  may be rotated while being connected to the rotation operation portion  333 , and the extending protrusions  332  may be rotated together with the rotation body  331 . Meanwhile, the fastened groove  222  may include a central groove  222   a  formed to have a shape corresponding to the rotation body  331  and through which the rotation body  331  passes, and include extending grooves  222   b  formed to extend from both sides of the central groove  222   a  in a radial direction and through which extending protrusions  332  pass. 
     Also, the extending protrusions  332  may be formed to have a thickness smaller than a length of the rotation body  331 . Consequently, when the fastening portion  330  is inserted into one side of the attached block  220  and is located in a state of passing through the other surface of the attached block  220 , the extending protrusions  332  may be located outside the other surface of the attached block  220 . Here, when the fastening portion  330  is rotated by an operation of the rotation operation portion  333 , the extending protrusions  332  may be pressed against the other surface of the attached block  220 . 
     In addition, a tapered surface may be formed on an outer circumference of the fastened groove  222  of the other side of the attached block  220  and may be inclined along a rotational direction of the fastening portion  330 . In more detail, the tapered surface may be formed to have a thickness gradually increasing from one surface of the attached block  220  from a position where the extending protrusions  332  initially come into contact to a position where the extending protrusions  332  are rotated by a preset angle when the fastening portion  330  rotates. 
     Accordingly, when the fastening portion  330  is rotated while being inserted into and passing through the fastened groove  222 , the extending protrusions  332  may be rotated by as much as the preset angle and be rotated while being pressed against the tapered surface such that the attached block  220  may be press-fastened to the moving grip portion  300 . 
     Meanwhile, the first coupling portion  210  may be located on the attached block  220 , and the first coupling portion  210  may be located to be recessed from one surface of the attached block  220  at a certain depth. Also, the second coupling portion  310  may be located to protrude from the moving block  340  in the same direction as that of the guide pin  320 . That is, when the at least two guide pins  320  are inserted into the at least two guide grooves  221 , the fastening portion  330  may be correspondingly inserted into the fastened groove  222  and the second coupling portion  310  may be inserted into and come into contact with a recession position of the first coupling portion  210 . 
     Accordingly, since the moving grip portion  300  and the nozzle assembly  200  are inserted and fastened at least four positions, contact with mutual fastening positions may be easily induced. Also, since the insertion structure of the at least two guide pins  320  and the at least two guide grooves  221  is continuously maintained in addition to fastening between the fastening portion  330  and the fastened groove  222 , it is possible to prevent an error in the printing operation caused by occurrence of vibrations, a gap between the moving grip portion  300  and the nozzle assembly  200 , or the like during the 3D printing operation. 
     According to embodiments of the present disclosure, it is possible to perform a 3D printing operation using any one selected from a plurality of nozzle assemblies and to perform replacement with any other of the plurality of nozzle assemblies. 
     Also, according to embodiments of the present disclosure, it is possible to alternately use a variety of materials having different properties according to a user&#39;s needs. 
     Also, according to embodiments of the present disclosure, it is possible to easily control coupling and separation of a nozzle assembly. 
     Also, according to embodiments of the present disclosure, it is possible to reduce vibrations and a load on a driving portion during separation of a nozzle assembly. 
     Also, according to embodiments of the present disclosure, it is possible to prevent heat from being generated at a coupled part while coupling of a nozzle assembly is maintained. 
     Although example embodiments of the present disclosure have been described in detail, it should be understood by those skilled in the art that various changes may be made without departing from the spirit or scope of the present disclosure. Therefore, the scope of the present disclosure is to be determined by the following claims and their equivalents, and is not restricted or limited by the foregoing detailed description.