CN108215166B

CN108215166B - Three-dimensional printer

Info

Publication number: CN108215166B
Application number: CN201810109780.1A
Authority: CN
Inventors: 林逢春; 吴立新; 李少阳; 胡中政
Original assignee: Quanzhou Bilined Technology Co Ltd
Current assignee: Quanzhou Bilined Technology Co Ltd
Priority date: 2017-06-21
Filing date: 2017-06-21
Publication date: 2019-12-24
Anticipated expiration: 2037-06-21
Also published as: CN108407279A; CN107020742A; CN107020742B; CN108407279B; CN108215166A

Abstract

The invention provides a practical three-dimensional printer, which breaks through the structural form of the traditional three-dimensional printer, simultaneously, a heating component further heats raw materials between a conveying shell and a conveying pipe, so that the temperature and the liquidity of the raw materials outside the conveying pipe are higher than those of the raw materials inside the conveying pipe, namely, the temperature and the liquidity of the raw materials flowing out of a lower discharging channel are higher than those of the raw materials flowing out of a third channel, in the printing process, a heating inclined plane is contacted with a slightly cooled and solidified printing layer of a lower layer, the upper surface of the printing layer of the lower layer can be melted, then the raw materials flowing out of the lower discharging channel are padded between the raw materials flowing out of the third channel and the lower printing layer with the melted surface, the raw materials flowing out of the lower discharging channel play a role in gluing, the raw materials flowing out of the third channel and the printing layer of the lower layer are naturally fused into a whole, and no obvious, the bond between adjacent printed layers is more secure.

Description

Three-dimensional printer

The patent application of the invention is a divisional application of Chinese patent application No. 201710474011.7, the application No. of the original application is 201710474011.7, the application date is 2017, 06 and 21, and the name of the invention is a three-dimensional printer with strong practicability.

Technical Field

The invention relates to the field of three-dimensional printing machinery, in particular to a three-dimensional printer.

Background

The three-dimensional Printer (3D Printer, 3DP for short) is a process of Rapid Prototyping (RP), and a three-dimensional model is manufactured layer by layer in a layer-by-layer stacking manner, and the operation process of the three-dimensional Printer is similar to that of a conventional Printer, except that the conventional Printer prints ink on paper to form a two-dimensional planar drawing, and the three-dimensional Printer stacks and superimposes liquid photosensitive resin materials, molten plastic wires, gypsum powder, metal powder and other materials layer by layer to form a three-dimensional entity by spraying a binder or extruding the like. The structure of a unit printer is known, for example, chinese patent 201310559350.7 discloses a fused deposition three-dimensional printing nozzle and a printer, wherein a fused deposition three-dimensional printing nozzle comprises a screw barrel, a nozzle, and a screw shaft, wherein the nozzle is installed at the lower part of the screw barrel, the screw shaft is installed in the screw barrel, the upper end of the screw shaft can be connected with a motor shaft through a coupling, a thread groove is opened on the lower half shaft, a branch pipe is opened at the upper part of the barrel body of the screw barrel for installing a plasticizing pipe for feeding threads, and heating devices are installed at the peripheries of the screw barrel and the branch pipe. The number of the branch pipes is three, and the branch pipes are uniformly arranged at the upper part of the barrel body of the screw machine barrel. The lower part of the screw machine barrel is provided with an external thread, the nozzle is provided with an internal thread matched with the external thread at the lower part of the screw machine barrel, and the nozzle is connected with the screw machine barrel in a thread matching way. And a thrust ball bearing and a bearing end cover are fixedly arranged in the top of the screw machine barrel, and the screw shaft penetrates through the thrust ball bearing and the bearing end cover. The heating device is composed of a heating sleeve and a thermistor, the silk material is melted by heat generated by the heating sleeve, the thermistor feeds back temperature information, and the whole heating device is a closed-loop temperature control system. The top of the screw machine barrel is provided with a through hole or a threaded hole for connecting with a printer. A fused deposition three-dimensional printer comprises the fused deposition three-dimensional printing spray head.

The invention can generate stable driving force to effectively push the molten silk material to be extruded from a nozzle, but in the actual use process, the invention is the same as other three-dimensional printers in the market, in the printing process of stacking raw materials layer by layer, the stacking of upper and lower printing layers has time difference, when the upper printing layer is laid on the lower printing layer, the lower printing layer is slightly cooled and solidified, the upper printing layer is only laid on the lower printing layer, an obvious joint surface exists, the joint surface is caused by incomplete fusion of the upper and lower printing layers, so that the three-dimensional printing finished product has poor integrity, is easy to break at the joint surface, becomes one of important defects of the three-dimensional printing finished product, and the smoothness of the conveyed raw materials needs to be improved.

Accordingly, the present inventors have made extensive studies to solve the above problems and have made the present invention.

Disclosure of Invention

The invention aims to provide a three-dimensional printer which can carry out complete melting type integrated joint on adjacent printing layers, has strong and firmer printing finished product integrity, smooth raw material flow and strong practicability.

In order to achieve the purpose, the invention adopts the following technical scheme:

a three-dimensional printer comprises a printer main body and a printing head arranged on the printer main body; the printing head comprises a conveying shell, a conveying pipe, a middle shaft, a conveying rod, a core rod and a discharging nozzle, wherein the conveying shell is arranged up and down, the conveying pipe is sleeved in the conveying shell, the middle shaft is sleeved in the conveying pipe above the conveying shell, the conveying rod is sleeved in the conveying shell and the conveying pipe below the conveying rod, the core rod is connected to the upper end of the conveying rod and penetrates through the middle shaft in an upward sliding mode, and the discharging nozzle is connected to; the conveying shell, the conveying pipe, the middle shaft, the conveying rod and the core rod are all coaxially arranged;

the conveying shell comprises a first conveying shell section positioned above, a second conveying shell section positioned below and a third conveying shell section which is connected between the first conveying shell section and the second conveying shell section and gradually thinned from top to bottom; the second conveying shell section is provided with a first channel for the conveying rod to slide in a matching way;

the conveying pipe comprises a first conveying section and a second conveying section, wherein the first conveying section is positioned above the conveying pipe and corresponds to the first conveying shell section, and the second conveying section is matched with the inner side surface of the third conveying shell section; a first conveying thread spirally extending from top to bottom is formed on the inner side surface of the first conveying section, and a second conveying thread spirally extending from top to bottom is formed on the outer side surface of the first conveying section; the upper end of the conveying pipe is provided with a first rotating driving device for driving the conveying pipe to rotate and a first lifting driving device for driving the conveying pipe to lift; a first through hole for the conveying rod to pass through in a matched and sliding manner is formed at the lower end of the second conveying section;

the upper end of the middle shaft is provided with a second rotation driving device which drives the middle shaft to rotate around the core rod in a direction opposite to the rotation direction of the conveying pipe;

a material guide hole which coaxially extends up and down is formed in the conveying rod, a plurality of feeding holes which extend obliquely upward from bottom to top to the peripheral surface of the conveying rod are arranged at the upper end of the material guide hole, and the plurality of feeding holes are uniformly distributed around the axis of the material guide hole; each feeding hole corresponds to the upper end and the lower end of the first through opening;

the upper end of the core rod is provided with a second lifting driving device for driving the core rod to lift;

the discharging nozzle comprises a first discharging section and a second discharging section, wherein the first discharging section is positioned above and connected with the lower end of the second conveying shell section, and the second discharging section is positioned below and gradually extends towards one side of the conveying shell in an inclined manner from top to bottom; the conveying shell is provided with a first side corresponding to the lower end of the second discharging section in an orientation mode and a second side opposite to the first side, the first discharging section is provided with a second channel communicated with the lower end of the material guide hole, the second discharging section is provided with a third channel communicated with the lower end of the second channel, and the second discharging section comprises a first inclined side wall close to the first side of the conveying shell and a second inclined side wall close to the second side of the conveying shell; the second inclined side wall is provided with an upper inclined surface positioned above and a lower inclined surface positioned below, and the distance between the upper inclined surface and the lower inclined surface is gradually reduced from top to bottom;

the second conveying shell section is provided with a first side wall and a second side wall, the first side wall is located on the same side of the first inclined side wall, the second side wall is located on the same side of the second inclined side wall, and the second side wall comprises an upper section corresponding to the conveying rod and a lower section corresponding to the second inclined side wall; the first channel is provided with a material guide channel extending from top to bottom at the upper section and the lower section; the material guide channel comprises an upper material discharge channel which is positioned above and corresponds to the conveying rod and the first material discharge section and is communicated with the third conveying shell section, and a lower material discharge channel which is positioned below and corresponds to the second material discharge section and gradually extends obliquely from top to bottom along the lower inclined surface towards the outlet direction of the third channel;

a heating part for heating the raw material between the conveying shell and the conveying pipe so that the temperature and the liquidity of the raw material between the conveying shell and the conveying pipe are both higher than those of the raw material in the conveying pipe is arranged in the side wall of the conveying shell; the heating part comprises a first heating section corresponding to the first conveying shell section, a second heating section corresponding to the third conveying shell section, a third heating section corresponding to the upper discharging channel and a fourth heating section corresponding to the lower discharging channel; the lower end of the lower section is provided with a heating inclined plane which is inclined and extends from top to bottom towards the outlet direction of the lower discharging channel.

The upper end of the second inclined side wall abuts against the lower end of the conveying rod, and a guide extension portion which extends towards the upper inclined surface and guides the raw materials in the material guide hole towards the third channel is formed at the lower end of the conveying rod.

The included angles between the third channel, the second inclined side wall, the lower discharging channel and the heating inclined plane and the horizontal plane become smaller in sequence, the included angle between the third channel and the horizontal plane is 15-30 degrees, and the included angle between the heating inclined plane and the horizontal plane is 5-15 degrees.

The conveying device is characterized in that a first heat-preservation and heat-insulation layer is arranged in the side wall of the conveying pipe, and a second heat-preservation and heat-insulation layer is coated outside the conveying shell.

The printing head further comprises a storage box which is positioned above the conveying shell and connected with the second heat-preservation and heat-insulation layer and used for storing the melted raw materials.

And a third heat-insulating layer is arranged in the side wall of the storage box.

A connecting plate is arranged above the storage box, a transmission section which extends upwards and penetrates above the connecting plate is arranged at the upper end of the conveying pipe, and the first rotating driving device and the first lifting driving device transmit the conveying pipe through the transmission section; the upper end of the middle shaft is provided with a first transmission rod which extends upwards to the lower surface of the connecting plate, and the second rotation driving device transmits the middle shaft through the first transmission rod; the upper end of the core rod is provided with a second transmission rod which extends upwards to penetrate above the connecting plate, and the second lifting driving device transmits the core rod through the second transmission rod.

The first rotation driving device and the second rotation driving device are both motors with output ends arranged on the upper surface of the connecting plate downwards, and the first lifting driving device and the second lifting driving device are both motors with output ends arranged on the upper surface of the connecting plate upwards; the first rotary driving device is fixed on the connecting plate through a fixing part;

the output end of the first rotary driving device is coaxially and fixedly connected with a first gear, and the outer peripheral surface of the upper end of the transmission section is provided with a first tooth section matched with the first gear; the output end of the second rotation driving device is coaxially and fixedly connected with a second gear, and a second tooth section matched with the second gear is formed on the peripheral surface of the upper end of the first transmission rod;

the output end of the first lifting driving device is used for lifting and driving the transmission section through a first horizontal transmission plate, the output end of the first lifting driving device is coaxially and fixedly connected with a first transmission screw rod, a first threaded hole matched with the first transmission screw rod is formed in the first horizontal transmission plate, and an annular groove for the first horizontal transmission plate to extend into is formed in the inner side of the upper end of the transmission section; the output end of the second lifting driving device is subjected to lifting transmission through a second horizontal transmission plate, the output end of the second lifting driving device is coaxially and fixedly connected with a second transmission screw rod, the second horizontal transmission plate is provided with a second threaded hole matched with the second transmission screw rod, and the upper end periphery of the second transmission rod is provided with a clamping groove for the second horizontal transmission plate to stretch into.

After the technical scheme is adopted, the three-dimensional printer breaks through the structural form of the traditional three-dimensional printer, in the actual working process, the material is supplied to the heating box by the material supply device, the heating box heats and melts the material into fluid, the melted material enters the printing head, the second side of the conveying shell is taken as the front of horizontal walking, and the printing head is driven by the action device to enable the third channel and the lower discharging channel to face backwards to perform three-dimensional printing on the printing platform. Specifically, in an unprinted state, the first lifting driving device drives the conveying pipe to downwards enable the lower end of the second conveying section to plug the upper end ports of the third conveying shell section and the first channel, the second lifting driving device drives the core rod to drive the conveying rod to downwards enable the feeding hole to be located below the upper end of the first through hole and enable the feeding hole to be plugged, when printing is started, the conveying pipe ascends under the driving of the first lifting driving device, the lower end of the second conveying section does not plug the upper end ports of the third conveying shell section and the first channel, the core rod drives the conveying rod to ascend for a larger distance, the feeding hole is higher than the upper end of the first through hole, the first rotating driving device drives the conveying pipe to rotate, molten raw materials are conveyed downwards from the inner side of the conveying pipe and sequentially flow out of the feeding hole, the material guide hole and the third channel, and the molten raw materials are conveyed downwards from the outer side of the conveying pipe and sequentially flow out of the third conveying shell section, The upper discharging channel and the lower discharging channel flow out and are padded below the raw material flowing out from the third channel; the heating component heats the conveying shell, so that the heating inclined plane at the lower end has higher temperature, and meanwhile, the heating component further heats the raw materials between the conveying shell and the conveying pipe, so that the temperature and the liquidity of the raw materials at the outer side of the conveying pipe are higher than those of the raw materials at the inner side of the conveying pipe, namely, the temperature and the liquidity of the raw materials flowing out of the lower discharging channel are higher than those of the raw materials flowing out of the third channel, in the printing process, the heating inclined plane is contacted with the lower printing layer which is cooled and solidified slightly, so that the upper surface of the lower printing layer is melted, then the raw materials flowing out of the lower discharging channel are padded between the raw materials flowing out of the third channel and the lower printing layer with the melted surface, the raw materials flowing out of the lower discharging channel play a role in gluing, the raw materials flowing out of the third channel and the lower printing layer are naturally fused into a whole, the joint between the adjacent printing layers is firmer, and meanwhile, the properties such as the flowability and the like of the raw materials in the third channel as the main raw materials for forming the printed finished product are unchanged, the design parameters such as the initial flowability and the like of the main raw materials are not changed, so that the condition that the quality is influenced by deformation and the like of the printed finished product in the printing process is ensured to be difficult to occur; aiming at the melted raw materials with larger fluidity, the invention can only independently lift the core rod to drive the conveying rod, and utilizes the first lifting driving device to drive the conveying pipe downwards, so that the lower end of the second conveying section plugs the third conveying shell section and the upper end opening of the first channel, and further only allows the raw materials inside the conveying pipe to flow out, and the raw materials in the conveying pipe and the lower printing layer with melted upper surface can be naturally integrated without the raw materials outside the conveying pipe. Compared with the prior art, the three-dimensional printer can carry out complete melting type integrated joint on the adjacent printing layers, the printed finished product has strong integrity and is firmer, the raw materials flow smoothly, and the practicability is strong.

Drawings

FIG. 1 is a simplified structural diagram of the present invention;

FIG. 2 is a first partial cross-sectional structural view of the present invention;

FIG. 3 is a partial sectional structural view illustrating a state of use of the present invention;

FIG. 4 is a second partial cross-sectional structural view of the present invention;

fig. 5 is a partial structural schematic diagram of the present invention.

In the figure:

1-printer body 11-printing platform 12-actuating device 13-heating box 14-feeding device 2-printing head

21-conveying shell body 211-first conveying shell section 212-second conveying shell section 2121-first channel 2122-first side wall 2123-second side wall a 1-upper section a 2-lower section a 21-heating inclined surface a 3-guide channel a 31-upper discharge channel a 32-lower discharge channel 213-third conveying shell section 214-second heat-insulating layer

22-conveying pipe 221-first conveying section 2211-first conveying screw 2212-second conveying screw 222-second conveying section 2221-first through opening 223-first rotary driving device 2231-fixing component 2232-first gear 224-first lifting driving device 2241-first horizontal driving plate 2242-first transmission screw 225-first heat insulation layer 226-transmission section 2261-first toothed section 2262-annular groove

23-center shaft 231-second rotary driving device 2311-second gear 232-first transmission rod 2321-second gear segment

24-conveying rod 241-guide hole 242-feed hole 243-guide extension part

25-core rod 251-second lifting driving device 2511-second horizontal driving plate 2512-second driving screw 252-second driving rod 2521-clamping groove

26-discharge nozzle 261-first discharge section 262-second discharge section 2621-third channel 2622-first inclined side wall 2623-second inclined side wall 26231-upper inclined surface 26232-lower inclined surface 27-heating member 271-first heating section 272-second heating section 273-third heating section 274-fourth heating section 28-storage box 281-third insulating layer 282-connecting plate.

Detailed Description

In order to further explain the technical solution of the present invention, the following detailed description is given by way of specific examples.

The three-dimensional printer disclosed by the invention comprises a printer main body 1 and a printing head 2 arranged on the printer main body 1, as shown in figures 1-5; the printer body 1 includes a printing platform 11, an actuating device 12 disposed above the printing platform 11 for actuating and driving the printing head 2, a heating box 13 disposed above the printing platform 11 for heating the raw material, and a feeding device 14 for feeding the heating box 13; the printing head 2 is arranged above the printing platform 11, is connected with the action device 12 and is communicated with a discharge hole of the heating box 13; the printing head 2 comprises a conveying shell 21 arranged up and down, a conveying pipe 22 sleeved in the conveying shell 21, a middle shaft 23 sleeved in the conveying pipe 22 at the upper part, a conveying rod 24 sleeved in the conveying shell 21 and the conveying pipe 22 at the lower part, a core rod 25 connected to the upper end of the conveying rod 24 and penetrating through the middle shaft 23 in an upward sliding manner, and a discharging nozzle 26 connected to the lower end of the conveying rod 24; the conveying shell 21, the conveying pipe 22, the middle shaft 23, the conveying rod 24 and the core rod 25 are all coaxially arranged;

the conveying shell 21 comprises a first conveying shell section 211 at the upper part, a second conveying shell section 212 at the lower part and a third conveying shell section 213 which is connected between the first conveying shell section 211 and the second conveying shell section 212 and is tapered from top to bottom; the second transport shell section 212 has a first channel 2121 for the transport rod 24 to matingly slide through;

the conveying pipe 22 comprises a first conveying section 221 which is arranged above and corresponds to the first conveying shell section 211, and a second conveying section 222 which is matched with the inner side surface of the third conveying shell section 213; a first conveying thread 2211 spirally extending from top to bottom is formed on the inner side surface of the first conveying section 221, and a second conveying thread 2212 spirally extending from top to bottom is formed on the outer side surface of the first conveying section 221; a first rotating driving device 223 for driving the conveying pipe 22 to rotate and a first lifting driving device 224 for driving the conveying pipe 22 to lift are arranged at the upper end of the conveying pipe 22; the lower end of the second conveying section 222 is formed with a first through hole 2221 for the conveying rod 24 to slide through;

the upper end of the middle shaft 23 is provided with a second rotary driving device 231 which drives the middle shaft 23 to rotate around the core rod 25 in the direction opposite to the rotating direction of the conveying pipe 22; thus, when the conveying pipe 22 is conveying, the rotation directions of the central shaft 23 and the conveying pipe 22 are opposite, so that the outer surface of the central shaft 23 can drive the melted raw material to make stronger relative movement with respect to the conveying pipe 22 and the first conveying screw 2211, and the downward conveying of the raw material in the conveying pipe 22 is facilitated.

A material guide hole 241 coaxially extending up and down is formed in the conveying rod 24, a plurality of feeding holes 242 extending obliquely upward from bottom to top to the peripheral surface of the conveying rod 24 are arranged at the upper end of the material guide hole 241, and the plurality of feeding holes 242 are uniformly distributed around the axis of the material guide hole 241, so that the feeding uniformity of the feeding holes 242 can be ensured; each feed hole 242 corresponds to the upper end and the lower end of the first through opening 2221;

a second lifting driving device 251 for driving the core rod 25 to lift is arranged at the upper end of the core rod 25;

the discharging nozzle 26 comprises a first discharging section 261 which is arranged above and connected with the lower end of the second conveying shell section 212, and a second discharging section 262 which is arranged below and gradually extends towards one side of the conveying shell 21 in an inclined way from top to bottom; the conveying shell 21 is provided with a first side corresponding to the lower end of the second discharging section 262 in a facing mode and a second side opposite to the first side, the first discharging section 261 is provided with a second channel communicated with the lower end of the material guide hole 241, the second discharging section 262 is provided with a third channel 2621 communicated with the lower end of the second channel, and the second discharging section 262 comprises a first inclined side wall 2622 closer to the first side of the conveying shell 21 and a second inclined side wall 2623 closer to the second side of the conveying shell 21; the second inclined side wall 2623 is provided with an upper inclined surface 26231 positioned above and a lower inclined surface 26232 positioned below, the distance between the upper inclined surface 26231 and the lower inclined surface 26232 is gradually reduced from top to bottom, the structure is convenient for the raw material flowing out of the lower discharge channel a32 to gradually and naturally contact and fuse with the raw material flowing out of the third channel 2621, the combination effect is better, and foam and the like are not easily generated to influence the strength of a finished product;

the second transporting shell section 212 has a first side wall 2122 on the same side as the first inclined side wall 2622 and a second side wall 2123 on the same side as the second inclined side wall 2623, the second side wall 2123 including an upper section a1 corresponding to the transporting rod 24 and a lower section a2 corresponding to the second inclined side wall 2623; the first channel 2121 is provided with a material guiding channel a3 extending from top to bottom at the upper section a1 and the lower section a 2; the material guiding channel a3 comprises an upper discharging channel a31 which is positioned above and corresponds to the conveying rod 24 and the first discharging section 261 and is communicated with the third conveying shell section 213, and a lower discharging channel a32 which is positioned below and corresponds to the second discharging section 262 and gradually extends from top to bottom along a lower inclined surface 26232 in an inclined manner towards the outlet direction of the third channel 2621;

a heating component 27 which heats the raw material between the conveying shell 21 and the conveying pipe 22 so that the temperature and the liquidity of the raw material between the conveying shell 21 and the conveying pipe 22 are both higher than those of the raw material in the conveying pipe 22 is arranged in the side wall of the conveying shell 21; the heating means 27 comprises a first heating section 271 corresponding to the first conveying shell section 211, a second heating section 272 corresponding to the third conveying shell section 213, a third heating section 273 corresponding to the upper discharge passage a31, and a fourth heating section 274 corresponding to the lower discharge passage a 32; the lower end of the lower segment a2 is formed with a heating inclined plane a21 which extends from top to bottom gradually towards the outlet of the lower discharging channel a32, the fourth heating segment 274 heats the heating inclined plane a21, so that the heating inclined plane a21 has a higher temperature, and the contacted lower printing layer can be melted. In the actual working process of the invention, the material supply device 14 supplies the raw material to the heating box 13, the heating box 13 heats and melts the raw material into fluid, the melted raw material enters the printing head 2, the second side of the conveying shell 21 is the front of the horizontal walking, and the printing head 2 drives the third channel 2621 and the lower discharge channel a32 to face backwards to perform three-dimensional printing on the printing platform 11 under the driving of the action device 12. Specifically, in a non-printing state, the first elevation driving device 224 drives the conveying pipe 22 to move down to enable the lower end of the second conveying section 222 to plug the upper end ports of the third conveying shell section 213 and the first passage 2121, the second elevation driving device 251 drives the core rod 25 to drive the conveying rod 24 to move down to enable the feed hole 242 to be located below the upper end of the first through opening 2221 to plug the feed hole 242, when printing is started, the conveying pipe 22 moves up under the driving of the first elevation driving device 224, the lower end of the second conveying section 222 does not plug the upper end ports of the third conveying shell section 213 and the first passage 2121, the core rod 25 drives the conveying rod 24 to move up for a larger distance, the feed hole 242 is higher than the upper end of the first through opening 2221, the first rotation driving device 223 drives the conveying pipe 22 to rotate to convey the melted raw material from the inner side of the conveying pipe 22 to move down to sequentially pass through the feed hole 242, the guide hole 241 and the third passage 2621 to flow out, meanwhile, the melted raw materials are conveyed downwards from the outer side of the conveying pipe 22 and sequentially flow out of the third conveying shell section 213, the upper discharge channel a31 and the lower discharge channel a32, and are padded below the raw materials flowing out of the third channel 2621; the heating component 27 heats the conveying shell 21, so that the heating inclined surface a21 at the lower end has a higher temperature, meanwhile, the heating component 27 further heats the raw material between the conveying shell 21 and the conveying pipe 22, so that the temperature and the flowability of the raw material at the outer side of the conveying pipe 22 are higher than those of the raw material at the inner side of the conveying pipe 22, namely, the temperature and the flowability of the raw material flowing out from the lower discharging channel a32 are higher than those of the raw material flowing out from the third channel 2621, in the printing process, the heating inclined surface a21 is in contact with the lower printing layer which is cooled and solidified slightly, so that the upper surface of the lower printing layer can be melted, then the raw material flowing out from the lower discharging channel a32 is filled between the raw material flowing out from the third channel 2621 and the lower printing layer with the melted surface, the raw material flowing out from the lower discharging channel a32 plays a role in gluing, and the raw material flowing out, obvious joint surfaces cannot be formed between the upper printing layer and the lower printing layer, the joint between the adjacent printing layers is firmer, meanwhile, the properties such as flowability and the like of the raw materials in the third channel 2621 as the main raw materials for forming the printed finished product can be ensured to be unchanged, the design parameters such as initial flowability and the like of the main raw materials are not changed, and the condition that the quality is influenced by deformation and the like of the printed finished product in the printing process is further ensured not to occur easily; for the melted raw material with larger fluidity, the invention can only raise the core rod 25 to drive the conveying rod 24, and utilize the first lifting driving device 224 to drive the conveying pipe 22 downwards, so that the lower end of the second conveying section 222 plugs the upper ports of the third conveying shell section 213 and the first channel 2121, and further only allows the raw material inside the conveying pipe 22 to flow out, and the raw material inside the conveying pipe 22 and the lower printing layer with melted upper surface can be naturally fused into a whole without the raw material outside the conveying pipe 22. Specifically, the print head 2 may be provided with a driving device for driving the print head 2 to rotate, and the driving device may rotationally adjust the print head 2 according to the direction of horizontal travel of the print head 2 during printing, so that the third channel 2621 and the lower discharge channel a32 face rearward. The heating member 27 may be an electric heating tube. The lower discharging channel a32 may be flat corresponding to the width of the third channel 2621. A first clamping block clamped at the lower end of the first side wall 2122 is formed at the upper end of the first discharging section 261, and a second clamping block clamped below the first clamping block is formed at the lower end of the first side wall 2122.

Preferably, the upper end of the second inclined side wall 2623 abuts against the lower end of the feeding rod 24, and the lower end of the feeding rod 24 is formed with a guiding extension 243 extending upward from the inclined surface 26231 and guiding the raw material in the guiding hole 241 toward the third channel 2621. In the practical use process of the present invention, the upper end of the second inclined side wall 2623 can limit the position of the feeding rod 24, and the guiding extension portion 243 can guide the raw material flowing out from the material guiding hole 241, especially after the feeding tube 22 ascends, the guiding extension portion 243 enables the raw material to smoothly flow out from the third channel 2621, so as to avoid entering the lower discharging channel a32 to mix with the raw material in the material guiding channel a 3.

Preferably, the included angles between the third channel 2621, the second inclined side wall 2623, the lower discharging channel a32 and the heating inclined plane a21 and the horizontal plane become smaller in turn, so that the third channel 2621 and the lower discharging channel a32 are more and more gathered from top to bottom, the raw material flowing out of the third channel 2621 is more conveniently contacted and combined with the raw material flowing out of the lower discharging channel a32, and the included angle between the third channel 2621 and the horizontal plane is 15-30 degrees, the specific angle can be 15, 20, 25 or 30 degrees, the arrangement of the inclined angle is more convenient for the raw material in the third channel 2621 to flow out and lay on the raw material flowing out from the lower discharging channel a32, the included angle between the heating inclined plane a21 and the horizontal plane is 5-15 degrees, the specific angle can be 5, 8, 10, 13 or 15 degrees, the arrangement of the inclined angle is more convenient for the heating inclined plane a21 to be in direct contact with the lower printing layer, the effective heating area is large enough, and the melting of the upper surface of the lower printing layer is more convenient.

Preferably, a first thermal insulation layer 225 is arranged in the side wall of the conveying pipe 22, and a second thermal insulation layer 214 is coated outside the conveying shell 21. In the actual use process of the invention, the first heat-preserving and heat-insulating layer 225 can prevent the heat of the raw materials outside the heating component 27 and the conveying pipe 22 from being transferred to the raw materials in the conveying pipe 22, prevent the normal design flowability of the raw materials in the conveying pipe 22 from being affected, and further ensure the quality of the finished product; the second heat-insulating layer 214 can ensure the heat-insulating effect of the whole printing head 2, and can effectively protect external objects, and at least can not scald workers.

Preferably, the print head 2 further comprises a storage box 28 connected with the conveying shell 21 and the second heat insulation layer 214 at the upper part for storing the melting raw material, and the storage box 28 is communicated with the heating box 13. In the practical use process of the present invention, the storage box 28 can collect and store the melted raw materials in the heating box 13, and then supply the materials to the inner side and the outer side of the conveying pipe 22 at the same time, so as to ensure the continuity and the stability of the materials.

Preferably, a third thermal insulating layer 281 is provided in the side wall of the magazine 28. In the practical use process of the present invention, the third thermal insulation layer 281 can ensure the thermal insulation effect of the storage box 28, so as to ensure that the melted raw material flowing from the heating box 13 has the required temperature and fluidity in the storage box 28.

Preferably, a connecting plate 282 is arranged above the magazine 28, a transmission section 226 extending upward and penetrating above the connecting plate 282 is arranged at the upper end of the delivery pipe 22, and the first rotating driving device 223 and the first lifting driving device 224 transmit the delivery pipe 22 through the transmission section 226; the upper end of the middle shaft 23 is provided with a first transmission rod 232 extending upwards to the lower surface of the connecting plate 282, and the second rotation driving device 231 transmits the middle shaft 23 through the first transmission rod 232; the upper end of the core bar 25 is provided with a second transmission rod 252 extending upwards and penetrating above the connection plate 282, and the second lifting driving device 251 transmits the core bar 25 through the second transmission rod 252.

Preferably, the first rotation driving device 223 and the second rotation driving device 231 are both motors with output ends facing downwards and arranged on the upper surface of the connection plate 282, and the first elevation driving device 224 and the second elevation driving device 251 are both motors with output ends facing upwards and arranged on the upper surface of the connection plate 282; first rotary drive 223 is fixed to attachment plate 282 by a fixing member 2231;

a first gear 2232 is coaxially and fixedly connected to an output end of the first rotary driving device 223, and a first tooth section 2261 matched with the first gear 2232 is formed on an outer peripheral surface of an upper end of the transmission section 226; the output end of the second rotation driving device 231 is coaxially and fixedly connected with a second gear 2311, and a second gear segment 2321 matched with the second gear 2311 is formed on the peripheral surface of the upper end of the first transmission rod 232;

the output end of the first lifting driving device 224 performs lifting transmission on the transmission section 226 through a first horizontal transmission plate 2241, the output end of the first lifting driving device 224 is coaxially and fixedly connected with a first transmission screw 2242, the first horizontal transmission plate 2241 is provided with a first threaded hole matched with the first transmission screw 2242, and the inner side of the upper end of the transmission section 226 is provided with an annular groove 2262 into which the first horizontal transmission plate 2241 extends; the output end of the second lifting driving device 251 drives the second transmission rod 252 to lift through a second horizontal transmission plate 2511, the output end of the second lifting driving device 251 is coaxially and fixedly connected with a second transmission screw 2512, a second threaded hole matched with the second transmission screw 2512 is formed in the second horizontal transmission plate 2511, and a clamping groove 2521 for the second horizontal transmission plate 2511 to extend into is formed on the circumferential surface of the upper end of the second transmission rod 252. In the practical use process of the present invention, the first rotary driving device 223 is matched with a first tooth section 2261 with a plurality of vertical strip-shaped teeth at the upper end of the transmission section 226 through a first gear 2232, so as to drive the transmission section 226 to rotate, and the transmission section 226 drives the conveying pipe 22 to rotate; the second rotation driving device 231 is matched with a second tooth section 2321 with a plurality of vertical strip-shaped teeth at the upper end of the first transmission rod 232 through a second gear 2311 to drive the first transmission rod 232 to rotate, and the first transmission rod 232 drives the middle shaft 23 to rotate; the first lifting driving device 224 drives the first horizontal transmission plate 2241 to lift through the first transmission screw 2242, the first horizontal transmission plate 2241 drives the transmission section 226 to lift through being clamped into the annular groove 2262 at the upper end of the transmission section 226, because the annular groove 2262 is annular around a circle, the rotation of the transmission section 226 does not affect the clamping relationship between the first horizontal transmission plate 2241 and the annular groove 2262, and the first gear 2232 is matched with the first tooth section 2261 through the vertically extending strip-shaped teeth, and the lifting of the transmission section 226 does not affect the matching relationship between the first gear 2232 and the first tooth section 2261; the second lifting driving device 251 drives the second horizontal driving plate 2511 to lift through the second driving screw 2512, and the second horizontal driving plate 2511 drives the second driving rod 252 to lift by being clamped into the clamping groove 2521 at the upper end of the second driving rod 252.

The product form of the present invention is not limited to the embodiments and examples shown in the present application, and any suitable changes or modifications of the similar ideas should be made without departing from the patent scope of the present invention.

Claims

1. A three-dimensional printer comprises a printer main body and a printing head arranged on the printer main body; the method is characterized in that: the printing head comprises a conveying shell, a conveying pipe, a middle shaft, a conveying rod, a core rod and a discharging nozzle, wherein the conveying shell is arranged up and down, the conveying pipe is sleeved in the conveying shell, the middle shaft is sleeved in the conveying pipe above the conveying shell, the conveying rod is sleeved in the conveying shell and the conveying pipe below the conveying rod, the core rod is connected to the upper end of the conveying rod and penetrates through the middle shaft in an upward sliding mode, and the discharging nozzle is connected to; the conveying shell, the conveying pipe, the middle shaft, the conveying rod and the core rod are all coaxially arranged;

2. The three-dimensional printer according to claim 1, characterized in that: the upper end of the second inclined side wall abuts against the lower end of the conveying rod, and a guide extension portion which extends towards the upper inclined surface and guides the raw materials in the material guide hole towards the third channel is formed at the lower end of the conveying rod.

3. The three-dimensional printer according to claim 2, characterized in that: the included angles between the third channel, the second inclined side wall, the lower discharging channel and the heating inclined plane and the horizontal plane become smaller in sequence, the included angle between the third channel and the horizontal plane is 15-30 degrees, and the included angle between the heating inclined plane and the horizontal plane is 5-15 degrees.

4. A three-dimensional printer according to any one of claims 1 to 3, characterised in that: the conveying device is characterized in that a first heat-preservation and heat-insulation layer is arranged in the side wall of the conveying pipe, and a second heat-preservation and heat-insulation layer is coated outside the conveying shell.

5. The three-dimensional printer according to claim 4, characterized in that: the printing head further comprises a storage box which is positioned above the conveying shell and connected with the second heat-preservation and heat-insulation layer and used for storing the melted raw materials.

6. The three-dimensional printer according to claim 5, characterized in that: and a third heat-insulating layer is arranged in the side wall of the storage box.

7. The three-dimensional printer according to claim 6, characterized in that: a connecting plate is arranged above the storage box, a transmission section which extends upwards and penetrates above the connecting plate is arranged at the upper end of the conveying pipe, and the first rotating driving device and the first lifting driving device transmit the conveying pipe through the transmission section; the upper end of the middle shaft is provided with a first transmission rod which extends upwards to the lower surface of the connecting plate, and the second rotation driving device transmits the middle shaft through the first transmission rod; the upper end of the core rod is provided with a second transmission rod which extends upwards to penetrate above the connecting plate, and the second lifting driving device transmits the core rod through the second transmission rod.

8. The three-dimensional printer according to claim 7, characterized in that: the first rotation driving device and the second rotation driving device are both motors with output ends arranged on the upper surface of the connecting plate downwards, and the first lifting driving device and the second lifting driving device are both motors with output ends arranged on the upper surface of the connecting plate upwards; the first rotary driving device is fixed on the connecting plate through a fixing part;