A desktop 3D printing head and printing method for continuous fiber prepreg tape

Abstract

The application relates to the field of 3D printing technology and discloses a desktop 3D printing head for continuous fiber prepreg tape and a printing method, the 3D printing head comprising a rotating mechanism, a swinging mechanism and a connecting frame, the rotating mechanism being capable of driving the swinging mechanism to rotate through the connecting frame; the rotating mechanism comprises a rotating motor, and the swinging mechanism comprises a swinging motor, the rotating direction of the swinging motor being perpendicular to the rotating direction of the rotating motor; the main body comprises a mounting seat, a conveying module, a cutting module and a heating module, the mounting seat being connected with the swinging mechanism, the prepreg tape being capable of passing through the conveying module, the cutting module and the heating module, and the conveying module being capable of conveying the prepreg tape from the conveying module to the cutting module and the heating module; the cutting module is used for cutting the prepreg tape; the heating module comprises a heating block and a compression roller, the heating block being provided with a first channel, the prepreg tape being capable of passing through the first channel to the compression roller, and the compression roller being used for compacting the prepreg tape. The 3D printing head has the advantages of high degree of freedom, high printing quality and high printing efficiency.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of 3D printing, in particular to a desktop 3D printing head for continuous fiber prepreg tape and a printing method. BACKGROUND

[0002] Fiber-reinforced composites have been widely used in aerospace, national defense, automotive racing and medical devices due to their high specific strength, high specific modulus, low density and corrosion resistance, etc. The automatic placement technology of composite materials has the advantages of fast production speed, stable product quality and high reliability, and has become one of the most popular automatic forming technologies for fiber composites in recent years.

[0003] However, the continuous fiber prepreg tape placement forming technology is mainly concentrated on large part structures such as aircraft wings, cabins and doors, and mainly relies on mechanical arm to connect single filament bundle and multi-filament bundle filament head for placement on the surface of the prepared mold, which has high cost and is suitable for small part carbon fiber structure forming and placement. At present, the continuous fiber reinforced composite 3D printing technology, on the one hand, modifies the traditional resin 3D printing head, adds fiber dry wire into the hole, impregnates the fiber dry wire with resin in the heating cavity, and improves the printing process to realize the printing technology; on the other hand, the continuous fiber prepreg wire is directly printed through an extruder, a heating block and a printing nozzle. Although these continuous fiber 3D printers have realized the forming technology of composite structure parts, the fibers in the structure parts are free to lay between the filaments, and there is no pressure extrusion, which results in high porosity, low fiber content, low strength and poor quality of the fiber reinforced structure parts, and cannot guarantee the reliability; the printing head is connected with the X, Y and Z displacement platforms on the printer, and the movement freedom of the printing head itself is low, so it is difficult to realize printing for some complex curved surface structure parts; and the printing process is single filament printing, which has low printing efficiency. SUMMARY

[0004] In view of the above problems in the prior art, the technical problem to be solved by the present application is to provide a desktop 3D printing head for continuous fiber prepreg tape and a printing method, which has high freedom, high printing quality and high printing efficiency.

[0005] The technical solution adopted by the present application to solve the technical problem is to provide a desktop 3D printing head for continuous fiber prepreg tape, comprising:

[0006] A rotating mechanism, a swinging mechanism and a connecting frame, the rotating mechanism and the swinging mechanism are connected at both ends of the connecting frame, and the rotating mechanism can drive the swinging mechanism to rotate through the connecting frame; wherein the rotating mechanism comprises a rotating motor, the swinging mechanism comprises a swinging motor, and the rotating direction of the swinging motor is perpendicular to the rotating direction of the rotating motor;

[0007] The main body comprises a mounting base and a conveying module, a cutting module and a heating module arranged on the mounting base, the mounting base is connected with the swing mechanism, the prepreg can pass through the conveying module, the cutting module and the heating module, and the conveying module can convey the prepreg to the cutting module and the heating module; the cutting module is used for cutting the prepreg; the heating module comprises a heating block and a compression roller arranged on the heating block, the heating block is provided with a first channel, the prepreg can pass through the first channel to the compression roller, and the compression roller is used for compacting the prepreg.

[0008] Further, the connecting frame comprises a first mounting plate and a second mounting plate which are perpendicular to each other, the rotating mechanism is mounted on the first mounting plate, and the swing mechanism is mounted on the second mounting plate.

[0009] The swing mechanism can drive the main body to swing, and the rotating mechanism can drive the swing mechanism and the main body to rotate through the connecting frame.

[0010] Further, the rotating mechanism comprises a driving gear, a driven gear and an output flange, the driving gear is sleeved on the rotating motor, the driven gear is sleeved on the output flange and is engaged with the driving gear, and the output flange is fixedly connected with the first mounting plate.

[0011] The swing mechanism comprises a speed reducer which is connected between the output shaft of the swing motor and the mounting base.

[0012] Further, the heating module comprises a first support and a pressure sensor, the heating block is mounted on the first support, the pressure sensor is arranged between the first support and the mounting base and is used for detecting the pressure value applied by the compression roller to the prepreg, and a plurality of heating rods and a thermocouple are arranged in the heating block.

[0013] Further, the conveying module comprises a conveying motor, a driving wheel, a driven wheel and an extension mechanism, the conveying motor and the extension mechanism are arranged on the mounting base, the driving wheel is sleeved on the output shaft of the conveying motor, the driven wheel is arranged on the extension mechanism, the extension mechanism can drive the driven wheel to approach or move away from the driving wheel, and the prepreg can pass through between the driving wheel and the driven wheel.

[0014] Further, the extension mechanism comprises a lead screw motor and a mounting frame, the driven wheel is mounted on the mounting frame, the mounting frame is provided with a nut and a sliding block, the mounting base is provided with a sliding rail, a lead screw on the lead screw motor is connected with the nut, and the sliding block is slidably arranged on the sliding rail.

[0015] Further, the main body further comprises a tensioning module, the tensioning module comprises a second support, a tensioning wheel, a tensioning spring and a spring, the second support is arranged on the mounting seat, the tensioning wheel is arranged on the second support, the tensioning spring is installed on the second support through a bolt, and the spring is sleeved on the bolt, one end of the spring abuts against the spring, and the other end of the spring abuts against the second support, and the prepreg can pass between the tensioning spring and the tensioning wheel.

[0016] Further, the tensioning module further comprises a tension testing wheel arranged on the mounting seat and below the tensioning wheel, and a tension sensor is arranged on the tension testing wheel, and the prepreg can pass through the tension testing wheel.

[0017] Further, the conveying module further comprises a lead plate arranged on the mounting seat, and a through slot for the prepreg to pass through is arranged in the lead plate.

[0018] The cutting module comprises a cutting blade and an electromagnetic driving member for driving the cutting blade to perform extension and retraction movement, and the cutting blade is below the through slot.

[0019] The present application adopts the technical solution to solve the technical problem, and further proposes a printing method applied to the above-mentioned desktop 3D printing head for continuous fiber prepreg, and the 3D printing head is connected to the X, Y and Z displacement platforms of the 3D printer, and the printing method comprises:

[0020] The prepreg passes through the mounting seat, the conveying module, the cutting module and the first channel in sequence, and passes out from the bottom of the compression roller;

[0021] The heating module heats the prepreg, the conveying module conveys the prepreg to the cutting module and the heating module, and the rotating mechanism drives the swinging mechanism and the main body to rotate, and the swinging mechanism drives the main body to swing, so that the compression roller is always perpendicular to the printing surface.

[0022] The 3D printing head is driven to move, the heated prepreg is laid on the printing surface, and the prepreg is compacted by the compression roller.

[0023] When the range of laying the prepreg reaches a preset value, the cutting module cuts the prepreg.

[0024] Compared with the prior art, the present application has at least the following beneficial effects:

[0025] In the application, the swing mechanism, the connecting frame and the rotating mechanism are arranged on the main body of the 3D printing head in connection, the swing motor can drive the main body to swing, the rotating mechanism can drive the swing mechanism and the main body to swing together, that is, the direction in which the rotating mechanism drives the main body to rotate is perpendicular to the direction in which the swing motor drives the main body to swing, when in use, after the 3D printing head is connected to the X, Y and Z displacement platforms of the 3D printer, the rotating mechanism and the swing mechanism can form a five-degree-of-freedom motion system of the 3D printing head, can meet the forming printing of complex parts such as multi-curved surface and multi-angle laying, can be suitable for continuous fiber prepreg tape 3D printing, can realize moldless printing of finished products, and does not need to set a robot to work, is low in cost, saves printing time, and is convenient to operate. In addition, the pressure roller is arranged at the bottom, after the prepreg tape heated by the heating module is laid on the printing surface, the prepreg tape is compacted by the pressure roller, the specific pressure can be detected by the pressure sensor, and then the pressure is adjusted to be at a preset value, so that the compactness of the printed product is high and the mechanical property is good; and in the process that the prepreg tape is compacted by the pressure roller, the angle of the main body is adjusted in real time by the rotating mechanism and the swing mechanism, so that the 3D printing head can adapt to the printing of curved surfaces, and the pressure direction of the pressure roller is always perpendicular to the printing curved surface, so that the compacting quality of the pressure roller is ensured. The 3D printing head is mainly suitable for the continuous fiber prepreg tape with a width range of 2-6.35 mm, is higher in printing efficiency than the towpreg printer, and the quality of the printed product after compaction is better. BRIEF DESCRIPTION OF DRAWINGS

[0026] Figure 1 It is a schematic view of the overall structure of the 3D printing head of the application;

[0027] Figure 2 It is a schematic view of the overall structure of the 3D printing head of the application; Figure 1 It is a schematic view of the overall structure of the 3D printing head of the application;

[0028] Figure 3 It is a schematic view of the overall structure of the 3D printing head of the application;

[0029] Figure 4 It is a schematic view of the overall structure of the 3D printing head of the application;

[0030] Figure 5 It is a schematic view of the overall structure of the 3D printing head of the application; Figure 4 It is a schematic view of the overall structure of the 3D printing head of the application;

[0031] Figure 6 It is a schematic view of the overall structure of the 3D printing head of the application;

[0032] Figure 7 It is a schematic view of the overall structure of the 3D printing head of the application;

[0033] Figure 8 It is a schematic view of the overall structure of the 3D printing head of the application;

[0034] Figure 9 Fig. 2 is an assembly view of the cutting mechanism, heating module and lead plate;

[0035] Figure 10 Fig. 3 is a half cutaway view of the cutting mechanism, heating module and lead plate. Figure 9

[0036] Fig. 4 is a schematic view of the cutting mechanism, heating module and lead plate.

[0037] 1, rotating mechanism; 10, rotating motor; 11, driving gear; 12, driven gear; 13, output flange;

[0038] 2, swinging mechanism; 20, swinging motor; 21, speed reducer;

[0039] 3, connecting frame; 30, first mounting plate; 31, second mounting plate; 32, connecting plate;

[0040] 4, mounting seat; 40, slide rail; 41, second passage;

[0041] 5, conveying module; 50, conveying motor; 51, driving wheel; 52, driven wheel; 53, telescopic mechanism; 531, screw motor; 532, mounting frame; 533, nut; 534, sliding block; 54, lead plate; 541, through slot;

[0042] 6, cutting module; 60, cutting blade; 61, electromagnetic driving member;

[0043] 7, heating module; 70, heating block; 701, first passage; 702, thermocouple; 703, heating rod; 71, compression roller; 72, first support; 73, pressure sensor;

[0044] 8, tensioning module; 80, second support; 81, tensioning wheel; 82, tensioning spring piece; 83, spring; 84, bolt; 85, tension testing wheel; 86, tension sensor;

[0045] 90, heat insulation plate; 91, fan. DETAILED DESCRIPTION

[0046] The following is a specific embodiment of the present application and further describes the technical solutions of the present application in conjunction with the drawings, but the present application is not limited to these embodiments.

[0047] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present application are only used to explain the relative positional relationship, movement condition, etc. between components in a certain posture (as shown in the drawings), and if the certain posture changes, the directional indications will also change accordingly.

[0048] ​In addition, the descriptions such as "first", "second", "one", etc. in the present application are only for the purpose of description, and cannot be understood as indicating or implying the relative importance of the indicated technical features or implying the number of the indicated technical features. Therefore, the features defined as "first" and "second" can be explicitly or implicitly included at least one of the features. In the description of the present application, the meaning of "a plurality of" is at least two, such as two, three, etc., unless otherwise explicitly specified.

[0049] In the present application, unless otherwise explicitly specified and limited, the terms "connection", "fixation", etc. should be understood broadly, for example, "fixation" can be fixed connection, or detachable connection, or integral; can be mechanical connection, or electrical connection; can be direct connection, or indirect connection through intermediate medium; can be internal communication of two elements or interaction relationship between two elements, unless otherwise explicitly limited. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0050] In addition, the technical solutions of various embodiments of the present application can be combined with each other, but it must be based on the fact that a person skilled in the art can realize it, when the combination of technical solutions appears contradictory or unachievable, it should be considered that the combination of technical solutions does not exist, nor within the scope of protection required by the present application.

[0051] Embodiment one:

[0052] As shown in Figures 1-3 A desktop 3D printing head for continuous fiber prepreg tape, mainly suitable for 6.35mm continuous fiber reinforced prepreg tape. The 3D printing head mainly includes a rotating mechanism 1, a swinging mechanism 2, a connecting frame 3 and a 3D printing head main body, wherein the 3D printing head main body mainly includes a mounting seat 4, a conveying module 5, a cutting module 6, a heating module 7 and a tensioning module 8.

[0053] As shown in Figures 4-5 The rotating mechanism 1, the swinging mechanism 2 and the connecting frame 3: the rotating mechanism 1 and the swinging mechanism 2 are connected at both ends of the connecting frame 3, and the rotating mechanism 1 can drive the swinging mechanism 2 to rotate through the connecting frame 3; wherein the rotating mechanism 1 includes a rotating motor 10, the swinging mechanism 2 includes a swinging motor 20, and the rotating direction of the swinging motor 20 is perpendicular to the rotating direction of the rotating motor 10, so that the 3D printing head main body increases two degrees of freedom.

[0054] Specifically, the connecting frame 3 comprises a first mounting plate 30 and a second mounting plate 31 perpendicular to each other, and the first mounting plate 30 and the second mounting plate 31 are transitionally connected through a connecting plate 32 to avoid too large bending angle between the first mounting plate 30 and the second mounting plate 31, which affects the strength of the connecting frame 3. A plurality of bolt 84 through holes are formed on the first mounting plate 30 and the second mounting plate 31 to facilitate the connection of the rotating mechanism 1 and the swinging mechanism 2. The rotating mechanism 1 is mounted on the first mounting plate 30, specifically, is detachably fixed on the first mounting plate 30 through the bolt 84; the swinging mechanism 2 is mounted on the second mounting plate 31, also is detachably fixed on the second mounting plate 31 through the bolt 84. In the use process, the swinging mechanism 2 can drive the main body to swing, and the rotating mechanism 1 can drive the swinging mechanism 2 and the main body to rotate through the connecting frame 3.

[0055] The rotating mechanism 1 comprises a rotating motor 10, a driving gear 11, a driven gear 12 and an output flange 13, the driving gear 11 is sleeved on the rotating motor 10, the driven gear 12 is sleeved on the output flange 13 and is engaged with the driving gear 11, and the output flange 13 is fixedly connected with the first mounting plate 30 through the bolt 84; a conical roller bearing is sleeved on each of the upper and lower ends of the output flange 13, and the driven gear 12 is located between the two conical roller bearings. When the output flange 13 rotates, the conical roller bearings can reduce the resistance of the output flange 13 rotating. A plurality of bolt 84 through holes are formed on the flange plate of the output flange 13, corresponding to the bolt 84 through holes on the first mounting plate 30, and the two are connected and fixed through the plurality of bolts 84, so that the output flange 13 can transmit greater torque. The outer periphery of the driving gear 11, the driven gear 12 and the conical roller bearings can be wrapped by an outer shell to ensure that the transmission is not disturbed by the outside world. The rotating motor 10 is mounted on the outer shell, and the flange plate of the output flange 13 extends outside the outer shell, which is convenient for connecting with the first mounting plate 30. In actual use, the outer shell of the rotating mechanism 1 can be fixedly connected with the 3D printer, that is, the outer shell does not need to move in the use process.

[0056] The swinging mechanism 2 comprises a speed reducer 21 connected between the output shaft of the swinging motor 20 and the mounting seat 4, and the mounting seat 4 and the speed reducer 21 are connected through a connecting seat, and the swinging mechanism 2 is integrally mounted on the second mounting plate 31.

[0057] In practical use, this embodiment sets up a connected swing mechanism 2, a connecting frame 3, and a rotating mechanism 1 on the main body of the 3D printing head. The rotation of the swing motor 20 can drive the main body to swing, and the rotation of the rotating mechanism 1 can drive the swing mechanism 2 to swing together with the main body. That is, the direction in which the rotating mechanism 1 drives the main body to rotate is perpendicular to the direction in which the swing motor 20 drives the main body to swing. When in use, after the 3D printing head is connected to the X, Y, and Z displacement platforms of the 3D printer, the rotating mechanism 1 and the swing mechanism 2 can form a five-degree-of-freedom motion system of the 3D printing head, which can meet the molding and printing of complex parts such as multi-curved surfaces and multi-angle lay-up. It is applicable to continuous fiber prepreg tape 3D printing, realizes moldless printing of finished products, and does not require the use of robots. It is low-cost, saves printing time, and is easy to operate.

[0058] For example Figures 1-3 As shown, the main body of the 3D printing head includes a mounting base 4 and a tensioning module 8, a conveying module 5, a cutting module 6, and a heating module 7 disposed on the mounting base 4. The mounting base 4 is connected to the swing mechanism 2. The swing mechanism 2 drives the mounting base 4 to swing, thereby driving the other modules on the mounting base 4 to move. A second channel 41 is provided at the top of the mounting base 4, through which the prepreg tape can pass. The prepreg tape can pass sequentially through the tensioning module 8, the conveying module 5, the cutting module 6, and the heating module 7. The conveying module 5 can convey the prepreg tape to the cutting module 6 and the heating module 7. The cutting module 6 is used to cut the prepreg tape. When the laying distance of the prepreg tape reaches the target value, the prepreg tape is cut by the cutting module 6. The heating module 7 includes a heating block 70 and a pressure roller 71 disposed on the heating block 70. The heating block 70 is provided with a first channel 701, through which the prepreg tape can pass to the pressure roller 71. The pressure roller 71 is used to compact the prepreg tape.

[0059] like Figures 6-7As shown, the conveying module 5 comprises a conveying motor 50, a driving wheel 51, a driven wheel 52 and a telescopic mechanism 53, the conveying motor 50 and the telescopic mechanism 53 are arranged on the mounting base 4, the driving wheel 51 is sleeved on the output shaft of the conveying motor 50, the driven wheel 52 is arranged on the telescopic mechanism 53, and the telescopic mechanism 53 can drive the driven wheel 52 to move close to or away from the driving wheel 51, the prepreg can pass between the driving wheel 51 and the driven wheel 52, and the prepreg is conveyed by the driving wheel 51 and the driven wheel 52. Wherein, the telescopic mechanism 53 comprises a lead screw motor and a mounting frame 532, the driven wheel 52 is mounted on the mounting frame 532, wherein the mounting frame 532 is provided with a nut 533 and a sliding block 534, the mounting base 4 is provided with a sliding rail 40, the lead screw on the lead screw motor is connected with the nut 533, and the sliding block 534 is slidably arranged on the sliding rail 40, so as to realize clamping or loosening of the prepreg. The conveying module 5 further comprises a lead plate 54 arranged on the mounting base 4, the lead plate 54 is provided with a through groove 541 for the prepreg to pass through, and the prepreg passes through the through groove 541 and then enters the cutting module 6 and the heating module 7.

[0060] In use, the lead screw motor drives the lead screw to rotate, and the lead screw nut 533 structure formed by the lead screw and the nut 533 enables the mounting frame 532 to slide along the sliding rail 40, so that the driven wheel 52 moves towards the side close to the driving wheel 51, and the prepreg can be clamped; the conveying motor 50 rotates to drive the driving wheel 51 to rotate, and then the prepreg is transmitted forward, and at the same time, the driven wheel 52 rotates.

[0061] Preferably, as Figure 8 As shown, the main body further comprises a tensioning module 8, the tensioning module 8 comprises a second bracket 80, a tensioning wheel 81, a tensioning spring 82 and a spring 83, the second bracket 80 is arranged on the mounting base 4, the tensioning wheel 81 is arranged on the second bracket 80, the tensioning spring 82 is mounted on the second bracket 80 through a bolt 84, and the spring 83 is sleeved on the bolt 84, one end of the spring 83 abuts against the spring, and the other end of the spring 83 abuts against the second bracket 80, and the prepreg can pass between the tensioning spring 82 and the tensioning wheel 81. The bolt 84 is provided with a nut 533, and by screwing the bolt 84 and the nut 533, the compression amount of the spring 83 can be changed, and then the friction between the tensioning wheel 81 and the tensioning spring 82 can be changed, and the tensioning degree of the prepreg can be changed to meet different use scenarios.

[0062] The tensioning module 8 also includes a tension testing wheel 85, which is mounted on the mounting base 4 and located below the tensioning wheel 81. The tension testing wheel 85 is equipped with a tension sensor 86. The prepreg tape can pass through the tension testing wheel 85. The tension sensor 86 can detect the tension force of the tensioning module 8 on the prepreg tape so that the tension force can be adjusted to a suitable value.

[0063] like Figures 9-10 As shown, the heating module 7 includes a heating block 70, a pressure roller 71, a first support 72, and a pressure sensor 73. The heating block 70 is preferably a copper block, mounted on the first support 72, with heat insulation plates 90 on both sides to reduce heat loss. The pressure sensor 73 is located between the first support 72 and the mounting base 4, used to detect the pressure applied by the pressure roller 71 to the prepreg tape. The heating block 70 contains several heating rods 703 and thermocouples 702. The heating rods 703 are ceramic heating rods that generate heat when energized to heat the heating block 70. The thermocouples 702 are used to detect the temperature of the heating block 70, facilitating real-time temperature control by the temperature controller to ensure the temperature of the heating block 70 remains constant within the set range, heating the prepreg tape to the printing state, and then pressing it with the pressure roller 71 to form the final product. The cutting module 6 includes a cutting blade 60 and an electromagnetic drive unit 61 (which can be an electromagnet) for driving the cutting blade 60 to extend and retract. The cutting blade 60 is located below the through groove 541. The electromagnetic drive unit 61 drives the cutting blade 60 to extend and retract, thereby cutting the prepreg tape. Fans 91 are provided at the pressure sensor 73, the electromagnetic drive unit 61, and the lead screw motor to cool them and prevent failure due to excessive operating temperature.

[0064] In practical use, a pressure roller 71 is installed at the bottom of the 3D print head. After the prepreg tape, heated by the heating module 7, is laid on the printing surface, it is compacted by the pressure roller 71. The specific pressure is detected by the pressure sensor 73, and then adjusted to a preset value to ensure high density and good mechanical properties of the printed product. Furthermore, during the compaction process of the prepreg tape by the pressure roller 71, the angle of the main body is adjusted in real time by the rotation mechanism 1 and the swing mechanism 2, allowing the 3D print head to adapt to the printing surface. This ensures that the pressure direction of the pressure roller 71 is always perpendicular to the printing surface, guaranteeing the compaction quality. This 3D print head is mainly suitable for continuous fiber prepreg tapes with a width range of 2-6.35 mm. Compared to filament printers, it offers higher printing efficiency and produces better quality products after compaction.

[0065] Example 2:

[0066] A printing method applied to the desktop 3D printing head for continuous fiber prepreg tape in embodiment one, and the 3D printing head of embodiment one is connected to the X, Y, Z displacement platform of the 3D printer. The working principle of the 3D printing head in embodiment one is the printing method, and the method comprises:

[0067] The prepreg tape enters from the second channel 41 on the mounting seat 4, passes between the tensioning wheel 81 and the tensioning spring 82, the tension testing wheel 85, the driving wheel 51 and the driven wheel 52, the first channel 701 on the lead plate 54, the first channel 701 on the heating block 70, and exits from the bottom of the compression roller 71 in sequence;

[0068] The heating module 7 heats the prepreg tape, the conveying module 5 conveys the prepreg tape to the cutting module 6 and the heating module 7, and the rotating mechanism 1 drives the swing mechanism 2 and the main body to rotate, and the swing mechanism 2 drives the main body to swing, so that the compression roller 71 is always perpendicular to the printing surface;

[0069] Drive the 3D printing head to move, lay the heated prepreg tape on the printing surface, and compact the prepreg tape by the compression roller 71 to print the formed product;

[0070] When the range of laying the prepreg tape reaches the preset value, the cutting module 6 cuts the prepreg tape.

[0071] In this scheme, the 3D printing head has high degree of freedom, high printing quality and high printing efficiency.

Claims

1. A desktop 3D printing head for continuous fiber prepreg tape, characterized by, The application relates to a 3D printing head, which comprises a rotating mechanism, a swinging mechanism and a connecting frame, the rotating mechanism and the swinging mechanism are connected at two ends of the connecting frame respectively, and the rotating mechanism can drive the swinging mechanism to rotate through the connecting frame; wherein the rotating mechanism comprises a rotating motor, the swinging mechanism comprises a swinging motor, and the rotating direction of the swinging motor is perpendicular to the rotating direction of the rotating motor; a main body comprises a mounting seat and conveying, cutting and heating modules arranged on the mounting seat, the mounting seat is connected with the swinging mechanism, a prepreg can pass through the conveying, cutting and heating modules, and the conveying module can convey the prepreg from the conveying module to the cutting and heating modules; the cutting module is used for cutting the prepreg; the heating module comprises a heating block and a compression roller arranged on the heating block, the heating block is provided with a first channel, the prepreg can pass through the first channel to the compression roller, and the compression roller is used for compacting the prepreg; during the compacting process of the compression roller, the angle of the main body is adjusted in real time through the rotating mechanism and the swinging mechanism, so that the 3D printing head can be self-adapted to print a curved surface, and the pressure direction of the compression roller is always perpendicular to the curved surface; the connecting frame comprises first and second mounting plates which are perpendicular to each other, the rotating mechanism is mounted on the first mounting plate, and the swinging mechanism is mounted on the second mounting plate; the swinging mechanism can drive the main body to swing, and the rotating mechanism can drive the swinging mechanism and the main body to rotate through the connecting frame; the rotating mechanism comprises a driving gear, a driven gear and an output flange, the driving gear is sleeved on the rotating motor, the driven gear is sleeved on the output flange and is engaged with the driving gear, and the output flange is fixedly connected with the first mounting plate; the swinging mechanism comprises a speed reducer, and the speed reducer is connected between the output shaft of the swinging motor and the mounting seat; the conveying module comprises a conveying motor, a driving wheel, a driven wheel and an extension mechanism, the conveying motor and the extension mechanism are arranged on the mounting seat, the driving wheel is sleeved on the output shaft of the conveying motor, the driven wheel is arranged on the extension mechanism, and the extension mechanism can drive the driven wheel to approach or move away from the driving wheel, and the prepreg can pass through between the driving wheel and the driven wheel; the extension mechanism comprises a lead screw motor and a mounting frame, and the driven wheel is mounted on the mounting frame, wherein the mounting frame is provided with a nut and a sliding block, the mounting seat is provided with a sliding rail, a lead screw on the lead screw motor is connected with the nut, and the sliding block is slidably arranged on the sliding rail. ​ ​ ​ ​ ​ ​ The main body further comprises a tensioning module, which comprises a second support, a tensioning wheel, a tensioning spring and a spring, the second support is arranged on the mounting seat, the tensioning wheel is arranged on the second support, the tensioning spring is installed on the second support through a bolt, and the spring is sleeved on the bolt, one end of the spring abuts against the spring, and the other end of the spring abuts against the second support, and the prepreg can pass between the tensioning spring and the tensioning wheel. The heating module comprises a first support and a pressure sensor, the heating block is installed on the first support, the pressure sensor is arranged between the first support and the mounting seat, and is used for detecting the pressure value applied by the compression roller to the prepreg, and a plurality of heating rods and a thermocouple are arranged in the heating block.

2. A desktop 3D printing head for continuous fiber prepreg tape according to claim 1, characterized in that, The tensioning module further comprises a tension testing wheel arranged on the mounting seat and below the tensioning wheel, and a tension sensor is arranged on the tension testing wheel, and the prepreg can pass through the tension testing wheel.

3. A desktop 3D printing head for continuous fiber prepreg tape according to claim 1, wherein, The conveying module further comprises a lead plate arranged on the mounting seat, and a through groove for the prepreg to pass through is arranged in the lead plate. The cutting module comprises a cutting blade and an electromagnetic driving element for driving the cutting blade to perform extension and retraction movement, and the cutting blade is below the through groove.

4. A printing method applied to the desktop 3D printing head for continuous fiber prepreg tape according to any one of claims 1-2, and connecting the 3D printing head to the X, Y, Z displacement platform of the 3D printer, characterized in that, The printing method comprises: The prepreg passes through the mounting seat, the conveying module, the cutting module and the first channel in sequence, and is discharged from the bottom of the compression roller; The heating module heats the prepreg, the conveying module conveys the prepreg to the cutting module and the heating module, and the rotating mechanism drives the swinging mechanism and the main body to rotate, and the swinging mechanism drives the main body to swing, so that the compression roller is always perpendicular to the printing surface; The 3D printing head is driven to move, the heated prepreg is laid on the printing surface, and the prepreg is compacted by the compression roller; When the range of the laid prepreg reaches a preset value, the cutting module cuts the prepreg.

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