Double-print-head device for continuous fiber composite material and having tension device

Abstract

A double-print-head device for a continuous fiber composite material and having a tension device. The double-print-head device comprises a printing support frame (1), wherein the printing support frame (1) is provided with a continuous-fiber printing mechanism (5); a filament extrusion mechanism (3) is provided beside the continuous-fiber printing mechanism (5), and the filament extrusion mechanism (3) is connected to the printing support frame (1) by means of a double-nozzle switching mechanism (2); a fiber guide block (52) is provided below the continuous-fiber printing mechanism (5); a speed feedback follower wheel (53) is provided beside the fiber guide block (52), and the speed feedback follower wheel (53) is connected to a filament feeding fiber tension control encoder (54); and the double-nozzle switching mechanism (2) comprises a horizontal guide slide rail (21), a push-plate mounting plate (22), a positioning guide groove (23), a filament fixing plate (25) and a rear mounting plate (26). The device can realize free switching between two heads for printing, and also ensure the stability of continuous-fiber feeding, thereby improving the operating efficiency.

Description

Continuous fiber composite double printing head device with tension device TECHNICAL FIELD

[0001] The present application relates to a 3D printing device, in particular to a continuous fiber composite double printing head device with tension device. BACKGROUND

[0002] Continuous fiber reinforced composite 3D printing is a new type of additive manufacturing technology, which is to form a whole structure by continuously extruding the fiber pre-impregnated filament in the nozzle and stacking layer by layer with the movement of the 3D printing nozzle. The "double nozzle switching device" in the current commercial continuous fiber printer is mainly to solve the problem of material switching speed and accuracy in single nozzle printing. The existing switching device mainly uses belt or slider, through the synchronous reverse movement of the up and down position of the two printing heads, to realize the switching of the printing material. This scheme is not conducive to the printing condition of long-time printing and frequent switching of the printing head, and cannot guarantee the reliability of the relative position accuracy of the two printing heads after switching.

[0003] In addition, the tension pulling of the continuous fiber caused by the mismatch between the feeding speed and the moving speed is an important factor that causes fiber damage in printing and affects the printing quality. The current printing speed control of the printer only relies on the pre-set speed information, and cannot make corresponding adjustments according to the actual situation in printing, which is a key limitation to the stable printing and forming of large-scale continuous fiber components. SUMMARY

[0004] In order to solve the above problems, the present application discloses a continuous fiber composite double printing head device with tension device, which can realize the mutual free switching of double head printing, and the continuous fiber printing head adopts a floating extruder, which uses a rotary encoder lag following control method to solve the problem of inaccurate fiber conveying amount of the existing printing head.

[0005] A continuous fiber composite double printing head device with tension device, comprising a printing support frame; a continuous fiber printing mechanism is arranged on the printing support frame, wherein a wire extrusion mechanism is arranged beside the continuous fiber printing mechanism; the wire extrusion mechanism is connected with the printing support frame through a double nozzle switching mechanism; a fiber guide block is arranged below the continuous fiber printing mechanism; a speed feedback follow-up wheel is arranged beside the fiber guide block; the speed feedback follow-up wheel is connected with a wire feeding fiber force control encoder; the double nozzle switching mechanism comprises a horizontal guide slide rail, a push plate mounting plate, a positioning guide groove, a wire fixing plate and a rear mounting plate; the wire extrusion mechanism is fixed on the wire fixing plate; the side edge of the wire fixing plate is slidably connected with the rear mounting plate, and the top is provided with a positioning guide groove; the push plate mounting plate is slidably arranged on the horizontal guide slide rail; the positioning guide groove is inclined, and both ends are respectively provided with positioning clamping points matched with the follow-up rollers.

[0006] Further, one end of the rear mounting plate is provided with a double-head switching reset auxiliary mechanism; the double-head switching reset auxiliary mechanism comprises a stand, a spring and a pressing block; one end of the wire fixing plate extends the pressing block; a through hole is arranged on the pressing block for the stand to pass through; the spring is located at the bottom of the pressing block and is sleeved on the stand; the stand is welded and fixed on the rear mounting plate.

[0007] Further, a multi-channel water cooling module and a heating module are sequentially arranged below the discharge ends of the continuous fiber printing mechanism and the wire extrusion mechanism.

[0008] Further, a water cooling quick connector and a water cooling plug are respectively arranged on the water cooling module.

[0009] Further, an air cooling module is installed on the multi-channel water cooling module; the air cooling module comprises an air cooling support and a turbine fan; the turbine fan is fixed on the air cooling support.

[0010] Further, fiber force control mechanisms are respectively arranged at both ends of the continuous fiber printing mechanism, wherein the fiber force control mechanisms comprise force control fixing blocks; stand no.

[0011] Further, the driving motor drives the wire feeding wheel in the continuous fiber printing mechanism to rotate.

[0012] The working principle of the application is as follows:

[0013] The application can ensure the laying speed of the driving motor in time, effectively relieve the tension pulling during the wire feeding process, realize the stability of the wire feeding state, switch by using the double-nozzle switching mechanism, the push rod touches the limiting rod on the equipment during the movement of the printing head, the push plate mounting plate slides transversely with the horizontal guide slide rail during the pushing process, so as to drive the follow-up roller to slide along the positioning guide groove, so as to drive the switching of the up-down position of the wire extrusion mechanism, ensure that the continuous wire printing mechanism is switched at any time during the printing process, and interference is not caused; during the switching process, the cooperation between the stand column one and the reset spring one ensures the stability of the up-down movement of the extrusion mechanism;

[0014] The application realizes the preliminary feeding action of the continuous fiber by designing the limiting force control mechanism, when the continuous fiber printing mechanism receives the printing code information, the driving motor drives the wire feeding wheel in the continuous fiber printing mechanism to rotate according to the wire feeding speed in the printing information. At this moment, the continuous fiber drives the speed feedback follow-up wheel, and the wire fiber force control encoder obtains the actual feeding speed of the continuous fiber through the speed feedback follow-up wheel, and takes over the control right of the driving motor wire feeding speed. When the moving speed of the continuous fiber printing mechanism does not match the wire feeding speed during the printing process of the continuous fiber, the continuous fiber will be tensioned and pulled, and the relevant part structure of the driving motor will be pulled down, and the tolerance tension spring two of the fiber force control mechanism releases the tension by deformation, and temporarily relieves the damage of the fiber caused by sudden pulling. Synchronously, the wire fiber force control encoder detects the actual wire feeding speed slowing down caused by the fiber pulling, and controls the driving motor to accelerate to match the wire feeding speed and the movement.

[0015] The application has the following beneficial effects:

[0016] 1. The double-head printing is realized to be freely switched, the stability of the continuous fiber feeding is ensured, the precise and stable switching of the double-nozzle is realized in the continuous fiber printing process by the mechanical limiting trigger type double-nozzle switching auxiliary mechanism, and the printing quality is effectively avoided from being reduced or the printing from being failed due to the relative position change of the double-nozzle.

[0017] 2. The feeding auxiliary mechanism based on the active detection of the actual wire feeding speed is used, the continuous stability of the feeding state in the continuous fiber printing process is realized, and the fiber tension pulling caused by the mismatch between the wire feeding speed and the moving speed is effectively inhibited. BRIEF DESCRIPTION OF DRAWINGS

[0018] Fig. 1 is a structural schematic view of the application;

[0019] Fig. 2 is a rear view of Fig. 1.

[0020] Fig. 3 is an enlarged view of the cooperation state of the continuous fiber printing mechanism and the wire extrusion mechanism;

[0021] Fig. 1-4 shows a continuous fiber composite double printing head device with tension device according to the present embodiment, which comprises a printing support frame 1; the bottom of the printing support frame 1 is provided with an automatic leveling module 10; the printing support frame 1 is provided with a continuous fiber printing mechanism 5, and the continuous fiber printing mechanism 5 is provided with a wire extrusion mechanism 3, wherein the wire extrusion mechanism 3 is connected with the printing support frame 1 through a double nozzle switching mechanism 2. DETAILED DESCRIPTION

[0022] The present application will be further illustrated in conjunction with the accompanying drawings and specific embodiments, and it should be understood that the following specific embodiments are only used to illustrate the present application and not to limit the scope of the present application. It should be noted that the words "front", "back", "left", "right", "up" and "down" used in the following description refer to the directions in the drawings, and the words "in" and "out" refer to the directions towards or away from the geometric center of a particular component.

[0023] Fig. 1-4 shows a continuous fiber composite double printing head device with tension device according to the present embodiment, which comprises a printing support frame 1; the bottom of the printing support frame 1 is provided with an automatic leveling module 10; the printing support frame 1 is provided with a continuous fiber printing mechanism 5, and the continuous fiber printing mechanism 5 is provided with a wire extrusion mechanism 3, wherein the wire extrusion mechanism 3 is connected with the printing support frame 1 through a double nozzle switching mechanism 2.

[0024] Fig. 1-4 shows a continuous fiber composite double printing head device with tension device according to the present embodiment, which comprises a printing support frame 1; the bottom of the printing support frame 1 is provided with an automatic leveling module 10; the printing support frame 1 is provided with a continuous fiber printing mechanism 5, and the continuous fiber printing mechanism 5 is provided with a wire extrusion mechanism 3, wherein the wire extrusion mechanism 3 is connected with the printing support frame 1 through a double nozzle switching mechanism 2.

[0025] The double-jet switching mechanism 2 comprises a horizontal guide slide rail 21, a push plate mounting plate 22, a positioning guide groove 23, a wire fixing plate 25 and a rear mounting plate 26; the wire extrusion mechanism 3 is fixed on the wire fixing plate 25; wherein the side edge of the wire fixing plate 25 is in sliding connection with the rear mounting plate 26 and the top is provided with the positioning guide groove 23; the push plate mounting plate 22 is slidingly arranged on the horizontal guide slide rail 21; the bottom of the push plate mounting plate 22 is in sliding fit with the positioning guide groove 23 through a follow-up roller 27; the positioning guide groove 23 is in an inclined shape and the two ends are respectively provided with positioning clamping points matched with the follow-up roller 27; the end of the push plate mounting plate 22 away from the follow-up roller 27 is provided with a push rod 28.

[0026] One end of the rear mounting plate 26 is provided with a double-head switching reset auxiliary mechanism 24; the double-head switching reset auxiliary mechanism 24 comprises a stand 241, a spring 242 and a pressing block 243; wherein one end of the wire fixing plate 25 extends the pressing block 243; wherein the pressing block 243 is provided with a through hole for the stand 241 to pass through; wherein the spring 242 is located at the bottom of the pressing block 243 and is sleeved on the stand 241; wherein the stand 241 is welded and fixed on the rear mounting plate 26.

[0027] In the process of switching by the double-jet switching mechanism, the push rod touches the limiting rod on the equipment in the process of pushing, the push plate mounting plate 22 slides transversely with the horizontal guide slide rail 21, so as to drive the follow-up roller 27 to slide along the positioning guide groove 23; so as to drive the switching of the up and down positions of the wire extrusion mechanism 3, to ensure that the continuous wire printing mechanism is switched at any time in the process of printing and no interference is caused; in the process of switching, the cooperation between the stand 241 and the reset spring 242 ensures the stability of the up and down movement of the extrusion mechanism;

[0028] The printing support frame 1 is provided with a continuous fiber printing mechanism 5, wherein the continuous fiber printing mechanism 5 is provided with a wire extrusion mechanism 3 beside it; wherein the wire extrusion mechanism 3 is connected with the printing support frame 1 through the double-jet switching mechanism 2; wherein the continuous fiber printing mechanism 5 is provided with a fiber guide block 52 below; the fiber guide block 52 is provided with a speed feedback follow-up wheel 53 beside it; wherein the speed feedback follow-up wheel 53 is connected with a wire fiber force control encoder 54; a driving motor 8 drives the wire feeding wheel in the continuous fiber printing mechanism 5 to rotate. The two ends of the continuous fiber printing mechanism 5 are respectively provided with a fiber force control mechanism, wherein the fiber force control mechanism comprises a force control fixed block 55; wherein the printing support frame 1 is respectively provided with a stand 56 slidingly fitted with the force control fixed block 55; a spring 57 is sleeved on each stand 56.

[0029] The embodiment designs a limiting force control mechanism. When the continuous fiber printing mechanism 5 receives the printing code information, the driving motor 8 drives the fiber feeding wheel in the continuous fiber printing mechanism 5 to rotate according to the fiber feeding speed in the printing information, so as to realize the preliminary feeding action of the continuous fiber. At this moment, the continuous fiber drives the speed feedback follow-up wheel, and the fiber feeding force control encoder 54 acquires the actual feeding speed of the continuous fiber through the speed feedback follow-up wheel 56, and takes over the control right of the driving motor 8. When the movement speed of the continuous fiber printing mechanism does not match the fiber feeding speed during the printing process of the continuous fiber, the continuous fiber will be pulled and stretched, and the related part structure of the driving motor 8 will be pulled down. The tolerance tension spring 2 of the fiber force control mechanism releases the tension by deformation, and temporarily relieves the damage of the fiber caused by sudden pulling. Synchronously, the fiber feeding force control encoder detects the actual fiber feeding speed slowing down caused by the fiber pulling, and controls the driving motor to accelerate to match the fiber feeding speed and movement again.

[0030] The specific implementation control method comprises the following steps:

[0031] Step 1, the left head of the printing head is a short fiber printing head, and the right side is a continuous fiber printing head. A position sensor is installed at a position opposite to the left printing head. When the printing machine returns to the zero point in the Z direction, the relative position of the left printing head and the printing platform is determined through the position sensor. At the same time, the right printing head switches the relative position of the left printing head through the switching device. Therefore, the relative positions of the left and right printing heads to the printing platform can be determined simultaneously by using one position sensor.

[0032] Step 2, realize the collaborative printing of short fibers and continuous fibers, that is, the left printing head and the right printing head work in time-sharing and interleaving during the printing of one component. Taking the left printing head as an example, when the left printing head is in an active state, the right printing head is in a waiting state. When the left printing head starts printing, the printing head moves to the switching starting position according to the specified switching path of the printing head, and moves slowly from left to right. During the movement to the switching end position of the printing head, the lever hits the fixed lever on the printing machine. During this process, the lever moves along the fixed slide rail of the lever with the follow-up wheel at the end of the lever. Under the action of the positioning tension spring force of the printing head, the left printing head starts to rise during the left movement of the follow-up wheel. When the printing head moves to the switching end position of the printing head, the left printing head rises to the highest point under the constraint of the follow-up wheel and the follow-up wheel limiting slide, and the action of switching the left head to the right head is completed.

[0033] Step 3, at this time the right head is active, the head starts to execute the print head task, the 3D printer control mainboard starts to send the driving signal to control the stepper motor driver of the right head extruder, the stepper motor driver controls the stepper motor of the extruder to convey the continuous fiber of the target value length downward;

[0034] Step 4, the continuous fiber wire material is tangent to the feedback follow-up wheel of the rotary encoder, when the extruder conveys the continuous fiber downward, the follow-up wheel of the rotary encoder rotates counterclockwise follow-up under the action of the mechanism tension and the friction force of the continuous fiber wire material;

[0035] Step 5, the rotary encoder feeds back the rotation speed and direction of the follow-up wheel in real time during the rotation, the rotation speed and direction of the follow-up wheel of the rotary encoder is also the actual feeding speed of the continuous fiber, the rotary encoder outputs the signal to the rotary encoder signal receiving and processing unit;

[0036] Step 6, the rotary encoder signal receiving and processing unit analyzes and processes the feedback right head extruder feeding parameter value in real time, when the extruder feeds the continuous fiber wire material to the printing nozzle, the wire material is adhered to the printing body, after the 3D printer control mainboard releases the control right of the right continuous fiber printing head extruder, the right head extrusion stepper motor driver will synchronously switch to receive the control signal of the rotary encoder signal processing unit, thereafter the right extrusion stepper motor is controlled by the rotary encoder signal receiving and processing unit to control the continuous fiber feeding speed;

[0037] Step 7, during the process of switching the control right of the right head extrusion stepper motor between the 3D printer mainboard and the rotary encoder signal receiving and processing unit, the right head extrusion motor stops rotating, the printing state continues, at this time the continuous fiber state is that one end is adhered to the printing surface and the other end is held by the continuous fiber printing head extruder mechanism and the extruder is in a stopped rotating state, therefore the continuous fiber consumed in the process of switching the control right of the extruder is dragged by the movement of the printing head, the continuous fiber wire material drags the extruder motor floating on the spring, the extruder motor compresses the spring length to provide the continuous fiber consumed in the process, due to the extremely fast signal switching speed, the rotary encoder feedback signal controls the right head extrusion stepper motor driver to control the motor feeding during the tension spring compression process, the spring compression is released and the spring follow-up resets;

[0038] Step 8, the rotary encoder signal receiving and processing unit controls the right head extrusion stepper motor feeding speed, the actual consumption of the wire material and the compression amount of the tension spring to continuously maintain a dynamic balance, that is, when the actual consumption of the wire material is greater than the extrusion motor feeding length controlled by the rotary encoder, the extrusion motor compresses the tension spring to provide the difference between the extrusion motor feeding length controlled by the rotary encoder signal receiving and processing unit and the actual consumption length, at the same time the rotary encoder obtains the difference to improve the feeding speed to balance the difference, finally the actual consumption length of the continuous fiber and the extrusion motor feeding length remain consistent;

[0039] Step 9, after the right continuous fiber print head completes the printing task, the print head moves to the switching left head starting position, the print head moves from right to left, in the process of moving to the switching print head end position, the print head lever will hit the lever fixed on the printer, in the process, the lever with the lever end follow-up wheel moves along the lever fixed slide rail, under the action of the 24-print head positioning tension spring force, the left print head starts to descend in the process of the follow-up wheel moving to the left, until the print head moves to the print head switching end position, the left print head is constrained by the follow-up wheel and the follow-up wheel limiting slide to descend to the lowest point, from which the left head switching to the right head action is completed, the left head starts to be in active state and starts to execute the printing task.

[0040] Step 10, thus, a cycle of adjustment control is completed.

[0041] The technical means disclosed in the scheme of the present application is not limited to the technical means disclosed in the above-mentioned embodiments, but also includes the technical scheme composed of any combination of the above technical features.

Claims

1. A continuous fiber composite double printing head device with tension device, comprising a printing support frame (1), a continuous fiber printing mechanism (5) is arranged on the printing support frame (1), characterized in that: The continuous fiber printing mechanism (5) is provided with a wire extrusion mechanism (3) beside it, wherein the wire extrusion mechanism (3) is connected with the printing support frame (1) through a double-nozzle switching mechanism (2); a fiber guide block (52) is arranged below the continuous fiber printing mechanism (5), a speed feedback follow-up wheel (53) is arranged beside the fiber guide block (52), and the speed feedback follow-up wheel (53) is connected with a wire feeding fiber force control encoder (54); the double-nozzle switching mechanism (2) comprises a horizontal guide sliding rail (21), a push plate mounting plate (22), a positioning guide groove (23), a wire fixing plate (25) and a rear mounting plate (26); the wire extrusion mechanism (3) is fixed on the wire fixing plate (25), the side edge of the wire fixing plate (25) is slidably connected with the rear mounting plate (26), and the top of the wire fixing plate (25) is provided with the positioning guide groove (23); the push plate mounting plate (22) is slidably arranged on the horizontal guide sliding rail (21), the bottom of the push plate mounting plate (22) is slidably matched with the positioning guide groove (23) through a follow-up roller (27); one end of the push plate mounting plate (22) away from the follow-up roller (27) is provided with a push rod (28); the positioning guide groove (23) is inclined, and both ends of the positioning guide groove (23) are respectively provided with positioning clamping points matched with the follow-up roller (27).

2. A continuous fiber composite dual print head apparatus with tensioning device according to claim 1, characterized in that: One end of the rear mounting plate (26) is provided with a double-head switching reset auxiliary mechanism (24); the double-head switching reset auxiliary mechanism (24) comprises a stand column (241), a reset spring (242) and a pressing block (243); one end of the wire fixing plate (25) extends the pressing block (243); the pressing block (243) and the other end of the wire fixing plate (25) are both provided with through holes through which the stand column (241) passes; each reset spring (242) is sleeved on the stand column (241); and the stand column (241) is welded and fixed on the rear mounting plate (26).

3. A continuous fiber composite dual print head apparatus with tensioning device according to claim 1, characterized in that: A multi-channel water cooling module (7) and a heating module (9) are sequentially arranged below the discharge ends of the continuous fiber printing mechanism (5) and the wire extrusion mechanism (3); the water cooling module (7) is respectively provided with a water cooling quick connector (71) and a water cooling plug (72); the multi-channel water cooling module (4) is provided with an air cooling module (4); the air cooling module (4) comprises an air cooling support (42) and a turbine fan (41); the turbine fan (41) is fixed on the air cooling support (42).

4. A continuous fiber composite dual print head apparatus with tensioning device according to claim 1, characterized in that: Both ends of the continuous fiber printing mechanism (5) are respectively provided with a fiber force control mechanism, wherein the fiber force control mechanism comprises a force control fixed block (55); the printing support frame (1) is respectively provided with a stand column (56) slidably matched with the force control fixed block (55); each stand column (56) is sleeved with a tolerance tension spring (57).

5. A continuous fiber composite dual print head apparatus with tensioning device according to claim 1, characterized in that: A driving motor (8) drives a wire feeding wheel (81) in the wire extrusion mechanism (3) to rotate.

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