CN106493941A - A kind of fusion sediment type 3D printer of fast changeable printing head - Google Patents

Abstract

The invention discloses a fused deposition type 3D printer capable of rapidly replacing printing nozzles, which includes a printing table and a printing head, the printing head includes: a support plate; the printing nozzle is made of metal material, and is fixed on the printing nozzle bracket through the printing nozzle bracket The support plate; the heating device, including the electromagnetic induction coil, the electromagnetic induction coil is set outside the print nozzle, and fixed on the support plate through the coil bracket; the cooling device is used to cool the print nozzle, and is fixed on the support plate through the cooling bracket; the control The circuit is electrically connected with the electromagnetic induction coil and provides alternating voltage for the electromagnetic induction coil. The heating mechanism of the fused deposition type 3D printer of the present invention is separated from the printing nozzle mechanism, which is convenient for quick replacement of the printing nozzle.

Description

A fused deposition 3D printer that can quickly replace printing nozzles

technical field

The invention relates to the technical field of 3D printing, in particular to a fused deposition 3D printer capable of rapidly replacing printing nozzles.

Background technique

3D printing technology, also known as Rapid Prototyping Manufacturing (RP technology for short), is divided into selective laser sintering (SLS), stereolithography (SLA), laminated solid molding (LOM) and fused deposition according to different molding methods. Molding (FDM), etc. The biggest difference between the fused deposition modeling (FDM) rapid prototyping system and the SLA, LOM, and SLS systems is that FDM does not use a laser system.

Fused Deposition Modeling (FDM, Fused Deposition Modeling) is a molding method that utilizes the thermoplasticity of materials to heat and melt materials such as thermoplastics, extrude the fuse from a heated nozzle, and perform melt deposition according to the predetermined trajectory of the part.

At present, there are a wide variety of 3D printers based on the fused deposition method. Among them, the target group of desktop-level fused deposition 3D printers is personal applications, with relatively low precision and simple structure. Mostly, the stepper motor directly controls the displacement in the three directions of XYZ through a belt or a lead screw. The nozzle part uses a stepping motor to directly control the feeding and feeding speed of the material filament. At present, most 3D printer nozzles are difficult to achieve rapid replacement, and the materials used are limited to filamentous materials.

The Chinese patent document with the publication number CN105216327A discloses a melting extrusion device based on thermoplastic granular materials, which includes a screw extrusion mechanism, a heating mechanism, a feeding mechanism, a reduction transmission mechanism and a heat dissipation mechanism. The screw extrusion mechanism includes a screw, a barrel, and an extrusion print head at the lower part of the barrel; the heating mechanism includes a heating sleeve and a temperature control instrument; the feeding mechanism is connected to a material guide port on the upper side of the barrel; The deceleration transmission mechanism includes a servo motor or a stepping motor, a planetary reducer, a mounting base and bearings, etc.; the heat dissipation mechanism includes a heat sink and a fan; meanwhile, the present invention also provides a 3D printing method based on the melt extrusion device . However, the screw extrusion nozzle is difficult to manufacture and difficult to disassemble and clean.

Pneumatic extrusion nozzles are generally composed of four parts: nozzle, heating block, heat dissipation block, and heating rod. The nozzle has external threads, the heater block has internal threads, and the heat sink has internal threads. Screw the heater block onto the nozzle first, then the heat sink block onto the nozzle. The heating rod is inserted into the round hole on the heating block for heating. When the air pressure extrusion nozzle stops extruding, the melted printing material will flow down naturally under the action of gravity, which will affect the printing effect.

The Chinese patent document with the publication number CN105459397A discloses a drip-proof nozzle for fused deposition modeling 3D printers, including a feed tube, a heating block, a nozzle and a feeding mechanism. There is a feed channel on the feed tube, and the nozzle is fixed on the At the lower end of the feed pipe, the spout of the nozzle communicates with the feeding channel of the feed pipe; the feed pipe is set inside the heating block, and the feed pipe is fixedly connected with the heating block; the nozzle has an anti-drip mechanism, which includes The baffle plate at the discharge port of the material tube, the bottom end of the material guide tube is provided with a guide groove, the baffle plate is installed in the guide groove, and the baffle plate is matched with the guide groove; the baffle plate is connected with the stepping motor through the transmission mechanism, and the transmission mechanism will step The rotation of the feeding motor is converted into the translation of the baffle plate along the radial direction of the material guide tube, and the transmission mechanism drives the baffle plate step by step to close or open the discharge port of the material guide tube. Although the technology disclosed in this patent can prevent the shower head from dripping, its structure is relatively complicated.

In addition, the current heating method of 3D printers based on the fused deposition method is mostly the resistance wire directly heating the nozzle, which makes it difficult to quickly replace the nozzle.

Contents of the invention

The invention provides a fused deposition type 3D printer capable of quickly replacing the printing nozzle. The heating mechanism is separated from the printing nozzle mechanism, which facilitates the rapid replacement of the printing nozzle.

A fused deposition 3D printer capable of quickly replacing print nozzles, comprising a print table and a print head, the print head comprising:

support plate;

The printing nozzle is made of metal material and fixed on the support plate through the printing nozzle bracket;

The heating device includes an electromagnetic induction coil, which is set outside the printing nozzle and fixed on the support plate through the coil bracket;

The cooling device is used to cool the printing nozzle, and is fixed on the support plate through the cooling bracket;

The control circuit is electrically connected with the electromagnetic induction coil and provides alternating voltage for the electromagnetic induction coil.

The principle of electromagnetic induction heating is that the alternating current generated by the power supply generates an alternating magnetic field through the electromagnetic induction coil, and the magnetically permeable object is placed in it to cut the alternating magnetic force line, thereby generating an alternating current (ie eddy current) inside the object, and the eddy current makes the inside of the object The atoms of the material move irregularly at high speed, and the atoms collide and rub against each other to generate heat energy, which has the effect of heating the object.

The fused deposition 3D printer of the present invention adopts a non-contact electromagnetic induction heating method, and the heating element does not need to be fixedly installed on the printing nozzle, so that the printing nozzle can be easily disassembled; the induction heating speed is fast, and the printing efficiency can be improved.

In order to further improve the convenience of disassembly and assembly of the printing head of the fused deposition 3D printer of the present invention, preferably, the support plate is connected to the printing platform through a movable dovetail groove structure.

The dovetail structure can be secured by compression screws. The support plate and the printing table are connected through a movable dovetail structure. This connection method is simple in structure, and the printing head can be disassembled and installed on the printing table without tools. The printing head can be replaced as needed to adapt to a wider range of printing materials.

As preferably, the print head includes:

A cartridge having a cavity for holding printing material, including:

barrel,

The upper cover of the barrel is threadedly matched with one end of the barrel and has a conduit joint,

The lower cover of the barrel is threadedly matched with the other end of the barrel, and has a nozzle connector, and the nozzle connector has an external thread;

The connecting ring, the inner peripheral surface has an internal thread that cooperates with the thread on the nozzle connector;

The nozzle has a discharge port at one end and an external thread that cooperates with the internal thread on the inner peripheral surface of the connecting ring at the other end.

The print head adopts segmented design, which is convenient for disassembly, cleaning and replacement of parts. The sections of the print nozzle are connected by threads, which facilitates the assembly of the print nozzle and makes the accommodating cavity of the print nozzle more airtight.

The printing nozzle of the present invention can print liquid or melt into liquid materials at a certain temperature, such as hydrogel, acrylonitrile-butadiene-styrene plastic (ABS plastic), polylactic acid (PLA), low melting point metal, etc.; Direct printing of granular or powder materials without processing the printed materials into filaments makes it possible to test a small amount of printed materials and greatly shortens the test cycle.

Preferably, the electromagnetic induction coil includes a first induction coil wrapped outside the barrel and a second induction coil wrapped outside the connecting ring.

The first induction coil is used to heat the barrel, and the second induction coil is used to heat the nozzle in the connecting ring, which separates the heating of the barrel and the print head. The user can determine the temperature of the barrel and the print head according to the characteristics of the printing material, for example, The barrel can be heated to a lower temperature to melt the printing material, and then the printing material can be heated to a higher temperature at the nozzle to avoid oxidative decomposition of the printing material in a high temperature state for a long time, which is different from the traditional single temperature-controlled printing Compared with the nozzle, the printing nozzle of the present invention has a wider application range.

In order to accurately control the temperature of the printing nozzle, the temperature of the printing nozzle should be monitored in real time. As a preference, the fused deposition type 3D printer of the present invention also includes an infrared temperature sensing probe, which is used to sense the temperature of the printing nozzle, and is installed on the support through the sensing probe bracket. board.

The infrared temperature sensing probe is used to monitor the temperature of the printing nozzle, and the temperature measuring element does not need to be fixedly installed on the printing nozzle, which further makes the printing nozzle easy to disassemble.

Furthermore, the infrared temperature sensing probe includes a first temperature sensing probe for sensing the temperature of the barrel and a second temperature sensing probe for sensing the temperature of the nozzle.

As a preference, the outer surfaces of the barrel and the connecting ring are coated with high temperature resistant blackbody paint. Facilitates induction heating and infrared temperature measurement.

Preferably, the cooling device includes:

motor;

The fan blade is installed on the motor;

The motor fixing frame is used for fixing the motor and is fixedly installed on the support plate.

The cooling device provides good heat dissipation conditions for the barrel and nozzle, so that the printing material can be cooled rapidly after being extruded from the nozzle, and can improve the temperature control speed and accuracy of the barrel and nozzle, and improve the printing effect.

Preferably, the fused deposition 3D printer of the present invention further includes an air pressure control device, which is connected to the printing nozzle through a conduit.

Further preferably, the fused deposition 3D printer of the present invention further includes an air pressure control device connected to the conduit joint on the upper cover of the barrel through a conduit.

Further preferably, the air pressure control device includes:

Gas compressor to provide positive pressure for the barrel;

Vacuum pump to provide negative pressure for the barrel;

The control unit is electrically connected with the gas compressor and the vacuum pump, and controls the opening and closing of the gas compressor and the vacuum pump.

The air pressure control device of the fused deposition type 3D printer of the present invention includes a vacuum pump. When the fused deposition type 3D printer stops printing, the vacuum pump provides negative pressure for the barrel, so as to prevent the printing material melted in the barrel from dripping under its own gravity and affect the printing. Effect.

In order to improve the printing effect, preferably, the printing table is provided with a printing panel for receiving printing materials, and the printing panel has a heating function.

Compared with prior art, the beneficial effect of the present invention is:

(1) The fused deposition type 3D printer of the present invention adopts a non-contact electromagnetic induction heating method and an infrared induction temperature measurement method, and the heating element and the infrared temperature measurement element do not need to be fixedly installed on the printing nozzle, so that the printing nozzle is convenient to disassemble;

(2) The support plate and the printing table are connected by a movable dovetail structure, and the printing head can be disassembled and installed on the printing table without tools, and the printing head can be replaced as needed;

(3) The air pressure control device includes a vacuum pump. When the fused deposition 3D printer stops printing, the vacuum pump provides negative pressure for the material cylinder to prevent the melted printing material in the material cylinder from dripping under its own gravity and affect the printing effect.

Description of drawings

Figure 1 is a schematic structural view of the printing station;

Figure 2 is a schematic structural view of the print head;

Fig. 3 is a structural schematic diagram of a printing nozzle;

Fig. 4 is a schematic diagram of the movable dovetail groove structure.

In the figure: 1. Bottom plate; 2. Printing panel; 3. X-direction slide rail; 31. X-direction slide block; 4. Y-direction slide rail; 41. Y-direction slide block; 5. Z-direction slide rail; 6. Printing Head; 61, support plate; 611, first support plate; 612, fixed dovetail slot plate; 613, movable dovetail slot plate, 614, positioning hole; 615, positioning column; 616, compression screw; 62, print nozzle ; 621, the upper cover of the barrel; 622, the barrel; 623, the lower cover of the barrel; 624, the connecting ring; 625, the nozzle; 63, the printing head support; 64, the first induction coil; 65, the first induction coil support; 66. The second induction coil; 67. The second induction coil bracket; 68. The cooling fan; 69. The cooling bracket.

detailed description

The present invention will be described in further detail below in conjunction with the accompanying drawings and embodiments.

As shown in Figure 1, the fused deposition type 3D printer of the present invention that can quickly replace the printing nozzle includes the bottom plate 1, the printing frame, the printing head 6 and the driving printing head 6 mounted on the printing frame along the X axis, the Y axis and The motion mechanism that moves in the Z-axis direction, in this embodiment, the Z-axis direction is the vertical direction, and the X-axis, Y-axis, and Z-axis are perpendicular to each other.

Also include a gas compressor (not shown in the figure) to provide positive pressure for the barrel;

Vacuum pump (not shown in the figure), provides negative pressure for barrel;

The control unit (not shown in the figure) is electrically connected with the gas compressor and the vacuum pump, and controls the opening and closing of the gas compressor and the vacuum pump.

Athletic institutions include:

Two Y-direction slide rails 4 are respectively fixed on two opposite sides of the printing table; two Y-direction sliders 41 are respectively slidably arranged on the corresponding Y-direction slide rails 4, and the corresponding Y-direction timing belts Fixed; two Y-direction active synchronous pulley brackets, used to install the Y-direction stepping motor, Y-direction reducer and Y-direction active synchronous pulley on two Y-direction slide rails; Y-direction driven synchronous pulley bracket , for installing the Y-direction driven synchronous pulley on two Y-direction slide rails; two Y-direction stepping motors drive two Y-direction sliders 41 to move through the Y-direction synchronous belt. Each Y-direction belt is matched and installed on the Y-direction driving synchronous pulley and the Y-direction driven synchronous pulley. The two Y-axis drive motors rotate at a constant speed driven by the synchronous drive signal provided by the control unit. After being decelerated by the reducer, they drive two Y-direction active synchronous pulleys to rotate, drive two Y-direction belts to move, and drive two The Y-slider moves synchronously in the Y direction;

The X-direction slide rail 3 is fixed on two Y-direction sliders at both ends; the X-direction slider 31 slides on the X-direction slide rail 3, fixed with the X-direction timing belt, and has a Z-direction chute; The active synchronous pulley bracket is used to install the X-direction stepping motor, the X-direction reducer and the X-direction active synchronous pulley on two X-direction slide rails; the X-direction driven synchronous pulley bracket is used to install the X-direction The driven synchronous pulley is installed on two X-direction slide rails; the X-direction stepping motor moves under the driving signal provided by the control unit, and drives the X-direction active synchronous pulley to move after being decelerated by the reducer, and the X-direction active synchronization The pulley drives the X-direction synchronous belt matched with it to move and then drives the X-direction slider 31 to move;

The Z-direction slide rail 5 cooperates with the Z-direction chute of the X-direction slider; the Z-direction lead screw cooperates with the threaded hole on the X-direction slider 31; the Z-direction stepping motor is fixed on the Z-direction slide rail , driven by the driving signal provided by the control unit to drive the Z-direction lead screw to rotate, and then make the Z-direction slide rail 5 move in the Z direction relative to the X-direction slider 31 .

As shown in FIGS. 2 and 3 , the print head 6 is fixed on the lower end of the Z-direction slide rail 5 . Printhead 6 includes:

support plate 61;

The printing nozzle 62 is made of metal material, and is fixed on the support plate 61 through the printing nozzle bracket 63;

The heating device includes an electromagnetic induction coil, which is set outside the printing nozzle 62 and fixed on the support plate 61 through the coil bracket;

The heat dissipation fan 68 is used to cool the printing nozzle 62, and is fixed on the support plate 61 through the cooling bracket 69;

The control circuit is electrically connected with the electromagnetic induction coil.

The print head 62 includes:

A cartridge having a cavity for holding printing material, including:

Cylinder 622,

The barrel upper cover 621 is threadedly matched with one end of the cylinder body 622, and has a conduit joint, which is connected to the gas compressor and the vacuum pump through the conduit.

The barrel lower cover 623 is threadedly matched with the other end of the cylinder body 622, and has a nozzle connector, and the nozzle connector has an external thread;

Connecting ring 624, the inner peripheral surface has an internal thread that cooperates with the thread on the nozzle connector;

The nozzle 625 has a discharge port at one end, and an external thread that cooperates with the internal thread on the inner peripheral surface of the connecting ring 624 at the other end.

The barrel and connecting ring 624 are made of metal material, and the outer surface is coated with black body paint.

The electromagnetic induction coil includes a first induction coil 64 and a second induction coil 66 sheathed outside the barrel, and is respectively fixed on the support plate 61 by a first induction coil support 65 and a second induction coil support 67 .

The two ends of the first induction coil 64 and the second induction coil 66 are respectively connected to the control unit through wires, and an alternating magnetic field is generated under the driving of the alternating current provided by the control unit, and an eddy current is generated in the barrel and the connecting ring 624 to activate to the effect of heating the barrel and nozzle 625.

The fused deposition 3D printer of the present invention that can quickly replace the printing nozzle also includes a first temperature sensing probe (not shown in the figure) for sensing the temperature of the barrel and a second temperature sensing probe (not shown in the figure) for sensing the temperature of the nozzle 625 not shown).

As shown in FIG. 4 , the support plate 61 of the present invention is fixedly and detachably connected to the Z-direction slide rail through a movable dovetail groove structure.

The active dovetail structure includes:

The first support plate 611 is used to carry the print head 6;

Fix the dovetail groove plate 612 and fix it at the lower end of the Z-direction slide rail 5;

The movable dovetail slot plate 613 cooperates with the positioning hole 614 on the fixed dovetail slot plate 612 through the positioning column 615;

Compression screw 616 cooperates with the threaded holes on the fixed dovetail slot plate 612 and the movable dovetail slot plate 613 to connect and compress the fixed dovetail slot plate 612 and the movable dovetail slot plate 613. The end of the compression screw 616 has Suitable for hand-tightened round heads.

The embodiments described above have described the technical solutions and beneficial effects of the present invention in detail. It should be understood that the above descriptions are only specific embodiments of the present invention, and are not intended to limit the present invention. All within the scope of the principles of the present invention Any modifications, supplements and equivalent replacements should be included within the protection scope of the present invention.

Claims (10)

1. the fusion sediment type 3D printer of a kind of fast changeable printing head, including stamp pad and printhead, its feature exists In described printhead includes：

Gripper shoe；

Printing head, is made using metal material, is fixed on the supporting plate by printing head support；

Heater, including electromagnetic induction coil, the electromagnetic induction coil is enclosed within outside printing head, is fixed on by coil brace In gripper shoe；

Cooling device, for cooling down printing head, is fixed on the supporting plate by cooling holder；

Control circuit, is electrically connected with described electromagnetic induction coil, provides alternating voltage for electromagnetic induction coil.

2. the fusion sediment type 3D printer of fast changeable printing head according to claim 1, it is characterised in that institute The gripper shoe that states is connected by movable dovetail slot structure with described stamp pad.

3. the fusion sediment type 3D printer of fast changeable printing head according to claim 1, it is characterised in that institute The printing head that states includes：

Barrel, the cavity with receiving printed material, including：

Cylinder,

Cover on barrel, coordinate with the cylinder threaded one end, with pipe joint,

Barrel lower cover, is coordinated with the cylinder other end screw thread, and with nozzle connector, the nozzle connector has outer spiral shell Line；

Connection ring, inner peripheral surface have and the internal thread cooperated for screw thread on the nozzle connector；

There is discharging opening, the other end there is the outer spiral shell cooperated with the internal thread on the connection ring inner peripheral surface for nozzle, one end Line.

4. the fusion sediment type 3D printer of fast changeable printing head according to claim 3, it is characterised in that institute The electromagnetic induction coil that states includes the first induction coil being enclosed within outside the barrel and second line of induction being enclosed within outside connection ring Circle.

5. the fusion sediment type 3D printer of fast changeable printing head according to claim 3, it is characterised in that also Including infrared temperature inductive probe, for sensing the temperature of the printing head, gripper shoe is arranged on by inductive probe support On.

6. the fusion sediment type 3D printer of fast changeable printing head according to claim 5, it is characterised in that institute The infrared temperature inductive probe that states is included for sensing the first temperature sense probe of the barrel temperature and described for sensing The second temperature inductive probe of nozzle temperature.

7. the fusion sediment type 3D printer of fast changeable printing head according to claim 3, it is characterised in that institute The barrel that states and on the outer surface of connection ring, scribble resistant to elevated temperatures black matrix paint.

8. the fusion sediment type 3D printer of fast changeable printing head according to claim 1, it is characterised in that institute The cooling device that states includes：

Motor；

Flabellum, on motor；

Motor fixing frame, for fixing motor, fixed installation is on the supporting plate.

9. the fusion sediment type 3D printer of fast changeable printing head according to claim 3, it is characterised in that also Including Pneumatic controller, it is connected with the pipe joint on lid on the barrel by conduit.

10. the fusion sediment type 3D printer of fast changeable printing head according to claim 9, it is characterised in that Described Pneumatic controller includes：

Gas compressor, provides malleation for barrel；

Vavuum pump, provides negative pressure for barrel；

Control unit, is electrically connected with gas compressor and vavuum pump, controls the open and close of gas compressor and vavuum pump.