Coaxial pressure ultrasonic peening assisted 3D printing device and method

Abstract

The invention relates to the technical field of 3D printing, in particular to a coaxial pressure ultrasonic peening assisted 3D printing device and method.The coaxial pressure ultrasonic peening assisted 3D printing device comprises a 3D printing nozzle, a peening head and an ultrasonic transducer, the 3D printing nozzle extrudes a printing wire along a planned printing path, the peening head and the 3D printing nozzle synchronously move, a vertically-through taper hole is formed in the peening head, and the ultrasonic transducer is arranged in the taper hole; a circular ring protruding downwards is arranged at the bottom end of the impact head, the circular ring and the taper hole are coaxially arranged, the 3D printing nozzle and the taper hole are coaxially arranged, the head of the 3D printing nozzle can downwards stretch out of the taper hole and the circular ring, and the 3D printing nozzle and the impact head do not make contact with each other; the impact head is connected with an ultrasonic transducer capable of enabling the impact head to generate vibration, the ultrasonic transducer is connected with a pressure control assembly capable of controlling the impact head to ascend and descend in the axial direction of the taper hole, and the pressure control assembly controls the impact head to apply appropriate pressure to the surface layer of the printing wire which is not completely solidified. The invention provides a 3D printing device and method capable of improving interlayer binding force.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of 3D printing, and in particular to a coaxial pressure ultrasonic impact assisted 3D printing device and method. BACKGROUND

[0002] Polymer and composite materials have good flowability and formability, light weight and high strength, corrosion resistance and good thermal insulation in the fused deposition (FDM) additive manufacturing technology, and have significant advantages such as making them widely used in aerospace, automotive industry, medical devices, consumer electronics, education and scientific research, and art design.

[0003] In the process of polymer and composite material additive manufacturing, the formed part has multiple interface characteristics, including the interface formed between adjacent printed filaments, the interface between adjacent printed layers, and the interface between the reinforcing material and the matrix when using composite materials. The multiple interface characteristics significantly affect the mechanical properties and overall structural integrity of the formed part, and are a key factor in improving the quality and function of additive manufacturing products.

[0004] In the process of polymer and composite material additive manufacturing, there may be problems such as difficulty in fully fusing fibers and resin, poor contact between adjacent filaments, and low interlayer adhesion, resulting in defects in the fiber / resin interface, filament separation, and layer separation in the formed part, which causes the polymer formed part to have defects such as pores and gaps in the multiple interfaces, seriously affecting its mechanical properties and forming quality.

[0005] At the same time, the existing ultrasonic assisted mechanism for enhancing the interlayer bonding force of polymer filaments is not coaxial with the printing head, so it has high requirements for the planned printing path and has great limitations in the printing direction, and cannot monitor and adjust the pressure of the ultrasonic impact head on the un-solidified material in real time, so it cannot ensure the constancy of the pressure in single printing and repeated printing. SUMMARY

[0006] The present application aims to provide a coaxial pressure ultrasonic impact assisted 3D printing device and method to solve the technical problems in the background art.

[0007] To achieve the above-mentioned purpose, the technical solution of the present application is as follows: A coaxial pressure ultrasonic impact assisted 3D printing device, comprising: a 3D printing nozzle, an impact head and an ultrasonic transducer, the 3D printing nozzle extrudes a printing wire along a planned printing path, the impact head moves synchronously with the 3D printing nozzle, a vertical through cone hole is formed on the impact head, a downward protruding circular ring is arranged at the bottom end of the impact head, the circular ring is coaxially arranged with the cone hole, the 3D printing nozzle is coaxially arranged with the cone hole, the head of the 3D printing nozzle can protrude downward out of the cone hole and the circular ring, and the 3D printing nozzle and the impact head do not contact each other; the impact head is connected with the ultrasonic transducer capable of generating vibration of the impact head, the ultrasonic transducer is connected with a pressure control assembly capable of controlling the impact head to ascend and descend along the axis of the cone hole, and the impact head is controlled by the pressure control assembly to be applied to the surface layer of the incompletely solidified printing wire with appropriate pressure.

[0008] Further, it further comprises: a printing support, a fixed plate one, a fixed plate two, a connecting plate and a mechanical arm, the printing support is fixedly installed at the end of the mechanical arm; a wire passing hole for the printing wire to pass through is formed on the printing support, a fixed plate one is vertically fixedly installed at the left bottom end of the printing support, a fixed plate two is vertically fixedly installed at the right rear end of the printing support, and the fixed plate one and the fixed plate two are perpendicular to each other; the left end of the fixed plate two is fixedly connected with the connecting plate, the left end of the connecting plate is sequentially provided from top to bottom with a wire feeding assembly, a water cooling assembly and a heating assembly, and the 3D printing nozzle is arranged at the bottom end of the heating assembly; the pressure control assembly is connected to the fixed plate two.

[0009] Further, it further comprises: a back-shaped frame and a side plate, the side plate is symmetrically provided with two, the back-shaped frame is arranged directly below the printing support, the front parts of the left and right sides of the back-shaped frame are respectively fixedly connected with the lower parts of the opposite sides of two side plates, the upper parts of the opposite sides of the two side plates are respectively fixedly connected to the front parts of the left and right sides of the printing support, and the front end of the lower side of the fixed plate two is fixedly connected to the rear side of the back-shaped frame.

[0010] Furthermore, the wire feeding assembly includes: a wire feeding motor, a motor shaft, a wire feeding wheel, a hinge shaft, an L-shaped pressure plate, a pneumatic nozzle, a connecting shaft, a pressure wheel, and a pressure mechanism. The wire feeding motor is fixedly installed on the right end of the fixed plate. The left end of the wire feeding motor is provided with a motor shaft. The left end of the motor shaft movably passes through the fixed plate and the connecting plate, and the wire feeding wheel is coaxially fixedly installed on the left front of the connecting plate. The corner of the L-shaped pressure plate is hinged to the rear left side of the connecting plate via the hinge shaft. The L-shaped pressure plate has a vertically arranged stepped hole at the top of its horizontal part. The pneumatic nozzle is coaxially fixed at the top of the stepped hole. A pressure wheel is rotatably mounted on the rear vertical part of the L-shaped pressure plate via a connecting shaft. The pressure wheel is correspondingly arranged with the filament feeding wheel. The L-shaped pressure plate is connected to a pressure mechanism for pressing the printing filament between the pressure wheel and the filament feeding wheel. The printing filament is fed into the stepped hole from the pneumatic nozzle and then pressed into contact with the pressure wheel and the filament feeding wheel respectively.

[0011] Furthermore, the water-cooling assembly includes: a water-cooling block, a water inlet, and a water outlet. The water-cooling block is fixedly installed on the lower left end of the connecting plate. The water-cooling block has a stepped hole (two holes) for the printing filament to pass through and is vertically arranged. A meandering flow channel is provided inside the water-cooling block. The lower front end of the water-cooling block has a water inlet and a water outlet sequentially arranged from bottom to top. The water inlet and the water outlet are respectively connected to the two ends of the meandering flow channel. The water inlet and the water outlet are respectively installed on the water inlet and the water outlet.

[0012] Furthermore, the clamping mechanism includes an upper positioning post, a lower positioning post, and a spring. The upper positioning post is vertically inserted through and fixedly installed on the front side of the horizontal part of the L-shaped pressure plate. The lower positioning post is vertically fixedly installed on the front side of the top end of the water-cooled block. The spring is respectively sleeved on the upper positioning post and the lower positioning post. The two ends of the spring press against the bottom end of the L-shaped pressure plate and the top end of the water-cooled block, respectively.

[0013] Furthermore, it also includes a throat tube. The heating assembly includes a heating block, an electric heating rod, and a temperature sensor. The upper part of the throat tube is coaxially fixedly installed at the lower part of the stepped hole. A vertical through-hole is provided on the heating block. The lower part of the throat tube is coaxially fixedly installed in the through-hole. The 3D printing nozzle is coaxially fixedly installed in the through-hole and docks with the lower part of the throat tube. An electric heating rod and a temperature sensor are installed sequentially from top to bottom on the left side of the heating block.

[0014] Furthermore, the pressure control assembly includes: clamp one, a pressure sensor, clamp two, and a sliding pair. The impact head consists of a horizontal flat plate segment and an inclined cylindrical segment. The inclined cylindrical segment of the impact head is fixedly connected to the right end of the horizontal flat plate segment of the impact head from left to right, and the bottom end of the inclined cylindrical segment of the impact head is horizontal and flush with the bottom end of the horizontal flat plate segment of the impact head. The ultrasonic transducer is cylindrical and has a flange segment in the middle. The bottom end of the ultrasonic transducer is coaxially fixedly installed at the top end of the inclined cylindrical segment of the impact head. Clamp one consists of an inclined flat plate segment and a horizontal flat plate segment. The inclined flat plate segment of clamp one... The first clamp is fixedly connected to the left end of the horizontal plate section of the first clamp at an angle from right to left. The inclined plate section of the first clamp has a vertically opened mounting hole through which the lower part of the ultrasonic transducer movably passes. The flange section of the ultrasonic transducer is fixedly connected to the top end of the inclined plate section of the first clamp. The second clamp is L-shaped, and the horizontal plate section of the second clamp is located directly above the horizontal plate section of the first clamp. The pressure sensor is fixedly installed between the horizontal plate sections of the first clamp and the second clamp. The vertical plate section of the second clamp is connected to the moving end of a sliding pair, which can move vertically.

[0015] Furthermore, the movable pair includes: a fixed base, a guide rail, a slider, a movable block, an end plate one, an end plate two, a stepper motor, a screw, and a bearing. The fixed base is fixedly installed at the front end of the fixed plate two. The guide rail is fixedly connected to the middle of the front end of the fixed base. The slider is vertically slidably connected to the guide rail. The front end of the slider is fixedly connected to the movable block. The vertical flat plate section of the clamp two is fixedly connected to the front end of the movable block. The upper and lower ends of the fixed base are respectively fixedly installed with end plate one and end plate two. The stepper motor is fixedly installed at the top end of end plate one. The upper end of the screw movably passes through end plate one and is fixedly connected to the output end of the stepper motor. The screw vertically passes through and is threadedly connected to the movable block. The lower end of the screw is rotatably installed on end plate two through a bearing.

[0016] A coaxial pressure ultrasonic impact-assisted 3D printing method, utilizing a 3D printing device, is described in detail below: The 3D printing device is started. The printing filament is fed from the pneumatic nozzle into the stepped hole one, then pressed into contact with the pressure roller and the filament feeding roller respectively. It then passes through the stepped hole two and the throat in the water-cooled block from top to bottom. After being heated and melted by the heating block, it is extruded from the 3D printing nozzle. The controller controls the robotic arm to drive the entire 3D printing device to print the filament along the planned printing path. After printing a section of filament, the pressure control component switches to pressure control mode, causing the impact head to move downward and exert impact and pressure on the molten printing filament. After printing one layer, the pressure control component switches to displacement control mode, controlling the bottom of the impact head to be higher than the printing plane, and starts printing the next layer. After printing a section of filament, the pressure control component switches to pressure control mode, causing the impact head to move downward and exert impact and pressure on the molten printing filament. This process is repeated layer by layer until the entire printed part is manufactured.

[0017] Compared with the prior art, the beneficial effects of the present invention are: Existing technologies employ a coaxial but fixed configuration of the ultrasonic impact head and the 3D printing nozzle. This approach restricts the printing path, requiring printing to proceed along the line connecting the impact head and the 3D printing nozzle to ensure effective ultrasonic impact on the printing filament. Furthermore, existing technologies utilize multi-axis motion control methods, with one axis controlling the 3D printing component and another controlling the ultrasonic impact component. This approach places high demands on the planning of both the printing path and the motion axis paths to ensure real-time ultrasonic impact on the incompletely solidified filament while closely following the 3D printing nozzle and avoiding interference from multiple motion axes during printing. In contrast, this invention proposes a coaxial impact head with the 3D printing nozzle. The impact head is unaffected by the printing path, consistently acting on the incompletely solidified material layer. This eliminates the need for complex path planning for the impact head and allows printing in any direction on the printing plane.

[0018] Compared with ordinary compaction mechanisms, this invention can reduce bubbles, pores, etc. that originally existed in the formed part by utilizing mechanical effects and ultrasonic cavitation effects under the dual action of pressure provided by the pressure control component and ultrasonic impact provided by the ultrasonic transducer, thereby improving the interlayer bonding force and other mechanical properties of the formed part.

[0019] Compared with other ultrasonic impact mechanisms, the pressure control component of this invention can accurately regulate the pressure applied by the impact head to the incompletely solidified material. Before the actual printing process, not only can a suitable pressure be selected according to different materials and other printing parameters, but also, according to the different printing paths of each layer, different but appropriate pressures can be set in the controller to complete the printing of the formed part.

[0020] Compared with other pneumatic ultrasonic impact mechanisms, the pressure control component of this invention uses a sliding pair to realize the up-and-down movement of the entire mechanism. Therefore, not only can the impact head generate a given arbitrary pressure on the incompletely solidified material to achieve pressure control, but it can also achieve arbitrary displacement adjustment in the up-and-down direction. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the structure of the present invention; Figure 2 This is a longitudinal sectional view of the invention at the pneumatic nozzle; Figure 3 This is a cross-sectional view of the invention at the motor shaft; Figure 4 This is a transverse longitudinal sectional view of the present invention at the pneumatic nozzle; Figure 5 This is a longitudinal sectional view of the invention at the screw. Figure 6 This is a rear-view perspective view of the present invention; Figure 7 This is a bottom view of the present invention; Figure 8 This is a schematic diagram showing the connection between the present invention and the robotic arm; Figure 9 This is a flowchart of the 3D printing method of the present invention.

[0022] The labels in the attached diagram are as follows: 1-Printing support, 101-Wire threading hole, 2-Fixing plate one, 3-Fixing plate two, 4-U-shaped frame, 5-Side plate, 6-Connecting plate, 7-Wire feeding motor, 8-Motor shaft, 9-Wire feeding wheel, 10-Hinge shaft, 11-L-shaped pressure plate, 1101-Stepped hole one, 12-Water cooling block, 1201-Stepped hole two, 1202-Circuitous flow channel, 1203-Water inlet, 1204-Water outlet, 13-Pneumatic nozzle, 14-Connecting shaft, 15-Pressure roller, 16-Upper positioning post, 17-Lower... Positioning pin, 18-Spring, 19-Inlet nozzle, 20-Outlet nozzle, 21-Throat, 22-Heating block, 23-3D printing nozzle, 24-Electric heating rod, 25-Temperature sensor, 26-Impact head, 2601-Conical hole, 27-Ultrasonic transducer, 28-Clamp one, 29-Pressure sensor, 30-Clamp two, 31-Fixed base, 32-Guide rail, 33-Slider, 34-Moving block, 35-End plate one, 36-End plate two, 37-Stepper motor, 38-Screw, 39-Bearing, 40-Robot arm. Detailed Implementation

[0023] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0024] See Figures 1-9As shown, a coaxial pressure ultrasonic impact-assisted 3D printing device includes: a 3D printing nozzle 23, an impact head 26, and an ultrasonic transducer 27. The 3D printing nozzle 23 extrudes printing filament along a planned printing path. The impact head 26 moves synchronously with the 3D printing nozzle 23. The impact head 26 has a vertically penetrating conical hole 2601. The bottom end of the impact head 26 has a downwardly protruding ring, which is coaxially arranged with the conical hole 2601. This ring is the contact part between the impact head 26 and the incompletely solidified printing filament. The 3D printing nozzle 23 is coaxially arranged with the conical hole 2601. The head of the 3D printing nozzle 23 can extend downward beyond the conical hole 2601 and the ring. The 3D printing nozzle 23 and the impact head 27 are connected. 6. The nozzles 23 and 26 are not in contact with each other to avoid affecting the vibration mode of the impact head and thus the effect of ultrasonic impact on enhancing interlayer bonding. An ultrasonic transducer 27 is connected to the impact head 26 to generate vibration. The ultrasonic transducer 27 is electrically connected to an ultrasonic generator, which provides a high-frequency electrical signal to the ultrasonic transducer 27. The ultrasonic transducer 27 converts the high-frequency electrical signal into high-frequency mechanical vibration and transmits it to the impact head 26. A pressure control component is connected to the ultrasonic transducer 27 to control the impact head 26 to move up and down along the axial direction of the conical hole 2601. The pressure control component controls the impact head 26 to apply appropriate pressure to the surface of the incompletely solidified printing filament.

[0025] In this embodiment, the 3D printing device further includes: a printing support 1, a first fixing plate 2, a second fixing plate 3, a connecting plate 6, and a robotic arm 40. The printing support 1 is fixedly installed at the end of the robotic arm 40. The printing support 1 has a filament threading hole 101 for the printing filament to pass through. The first fixing plate 2 is vertically fixedly installed on the left side of the bottom end of the printing support 1, and the second fixing plate 3 is vertically fixedly installed on the rear right side of the printing support 1. The first fixing plate 2 and the second fixing plate 3 are perpendicular to each other. The connecting plate 6 is fixedly connected to the left end of the second fixing plate 3. The left end of the connecting plate 6 is provided with a filament feeding assembly, a water cooling assembly, and a heating assembly from top to bottom. The 3D printing nozzle 23 is located at the bottom end of the heating assembly. The pressure control assembly is connected to the second fixing plate 3.

[0026] In this embodiment, the 3D printing device further includes: a spiral frame 4 and side plates 5. Two side plates 5 are symmetrically arranged on the left and right sides. The spiral frame 4 is located directly below the printing support 1. The front parts of the left and right sides of the spiral frame 4 are respectively fixedly connected to the lower parts of the two side plates 5 facing each other. The upper parts of the two side plates 5 facing each other are respectively fixedly connected to the front parts of the left and right sides of the printing support 1. The lower front end of the fixing plate 2 3 is fixedly connected to the rear side of the spiral frame 4.

[0027] In this embodiment, the wire feeding assembly includes: a wire feeding motor 7, a motor shaft 8, a wire feeding wheel 9, a hinge shaft 10, an L-shaped pressure plate 11, a pneumatic nozzle 13, a connecting shaft 14, a pressure wheel 15, and a pressure mechanism. The wire feeding motor 7 is fixedly installed on the right end of the fixed plate 2. The left end of the wire feeding motor 7 is provided with a motor shaft 8. The left end of the motor shaft 8 movably passes through the fixed plate 2 and the connecting plate 6, and the wire feeding wheel 9 is coaxially fixedly installed on the left front of the connecting plate 6. The corner of the L-shaped pressure plate 11 is hinged to the upper rear side of the left end of the connecting plate 6 through the hinge shaft 10. The top of the horizontal part of the L-shaped pressure plate 11 has a vertically arranged stepped hole 1101. The pneumatic nozzle 13 is coaxially fixedly installed at the top of the stepped hole 1101. The vertical part of the rear side of the L-shaped pressure plate 11 is rotatably mounted with a pressure wheel 15 through a connecting shaft 14. The pressure wheel 15 is correspondingly arranged with the filament feeding wheel 9. The L-shaped pressure plate 11 is connected to a pressure mechanism for pressing the printing filament between the pressure wheel 15 and the filament feeding wheel 9. The printing filament is fed from the pneumatic nozzle 13 into the stepped hole 1101, and then pressed into contact with the pressure wheel 15 and the filament feeding wheel 9 respectively.

[0028] In this embodiment, the water-cooling assembly includes: a water-cooling block 12, a water inlet 19, and a water outlet 20. The water-cooling block 12 is fixedly installed on the lower left end of the connecting plate 6. The water-cooling block 12 has a stepped hole 1201 for the printing filament to pass through and is vertically arranged. A meandering flow channel 1202 is provided inside the water-cooling block 12. The lower front end of the water-cooling block 12 has a water inlet 1203 and a water outlet 1204 arranged sequentially from bottom to top. The water inlet 1203 and the water outlet 1204 are respectively connected to the two ends of the meandering flow channel 1202. The water inlet 19 and the water outlet 20 are respectively installed on the water inlet 1203 and the water outlet 1204.

[0029] In this embodiment, the clamping mechanism includes an upper positioning post 16, a lower positioning post 17, and a spring 18. The upper positioning post 16 is vertically installed through and fixedly mounted on the front side of the horizontal part of the L-shaped pressure plate 11. The lower positioning post 17 is vertically fixedly mounted on the front side of the top end of the water-cooled block 12. The spring 18 is respectively sleeved on the upper positioning post 16 and the lower positioning post 17. The two ends of the spring 18 press against the bottom end of the L-shaped pressure plate 11 and the top end of the water-cooled block 12 respectively. The clamping mechanism can ensure that the printing filament is always pressed between the clamping wheel 15 and the feeding wheel 9.

[0030] In this embodiment, the 3D printing device further includes: a throat tube 21; a heating assembly including: a heating block 22, an electric heating rod 24, and a temperature sensor 25; the upper part of the throat tube 21 is coaxially fixedly installed at the lower part of the stepped hole 1201; a vertical through-hole is provided on the heating block 22; the lower part of the throat tube 21 is coaxially fixedly installed in the through-hole; the 3D printing nozzle 23 is coaxially fixedly installed in the through-hole and engages with the lower part of the throat tube 21; the electric heating rod 24 and the temperature sensor 25 are installed sequentially from top to bottom on the left side of the heating block 22; the heating assembly effectively heats the printing filament to ensure that it is fully melted and suitable for subsequent printing processes.

[0031] In this embodiment, the pressure control assembly includes: clamp 28, pressure sensor 29, clamp 30, and a sliding pair. The impact head 26 is composed of a horizontal flat plate segment and an inclined cylindrical segment. The inclined cylindrical segment of the impact head 26 is fixedly connected to the right end of the horizontal flat plate segment of the impact head 26 from left to right. The bottom end of the inclined cylindrical segment of the impact head 26 is horizontal and flush with the bottom end of the horizontal flat plate segment of the impact head 26. The ultrasonic transducer 27 is cylindrical and has a flange segment in the middle. The bottom end of the ultrasonic transducer 27 is coaxially fixedly installed on the top end of the inclined cylindrical segment of the impact head 26. Clamp 28 is composed of an inclined flat plate segment and a horizontal flat plate segment. The inclined flat plate segment of clamp 28... The first clamp 28 is fixedly connected to the left end of the horizontal plate section of the clamp from right to left. The inclined plate section of the clamp 28 has a vertical mounting hole, through which the lower part of the ultrasonic transducer 27 is movably inserted. The flange section of the ultrasonic transducer 27 is fixedly connected to the top end of the inclined plate section of the clamp 28. The second clamp 30 is L-shaped, and the horizontal plate section of the second clamp 30 is located directly above the horizontal plate section of the clamp 28. The pressure sensor 29 is fixedly installed between the horizontal plate section of the clamp 28 and the horizontal plate section of the second clamp 30. The moving end of the sliding pair is connected to the vertical plate section of the second clamp 30, and the moving end of the sliding pair can move in the vertical direction.

[0032] In this embodiment, the movable pair includes: a fixed base 31, a guide rail 32, a slider 33, a movable block 34, an end plate 35, an end plate 36, a stepper motor 37, a screw 38, and a bearing 39. The fixed base 31 is fixedly installed at the front end of the second fixed plate 36. The guide rail 32 is fixedly connected to the middle of the front end of the fixed base 31. The slider 33 is vertically slidably connected to the guide rail 32. The front end of the slider 33 is fixedly connected to the movable block 34. The vertical flat plate section of the clamp 30 is fixedly connected to the front end of the movable block 34. The upper and lower ends of the fixed base 31 are respectively fixedly installed with the first end plate 35 and the second end plate 36. The stepper motor 37 is fixedly installed at the top end of the first end plate 35. The upper end of the screw 38 movably passes through the first end plate 35 and is fixedly connected to the output end of the stepper motor 37. The screw 38 vertically passes through and is threadedly connected to the movable block 34. The lower end of the screw 38 is rotatably installed on the second end plate 36 through the bearing 39.

[0033] A coaxial pressure ultrasonic impact-assisted 3D printing method is described below: The 3D printing device is started, and the printing filament is fed from the pneumatic nozzle 13 into the stepped hole 1101. It then presses against the clamping roller 15 and the filament feeding roller 9, and passes from top to bottom through the stepped hole 1201 and the throat 21 in the water-cooling block 12. After being heated and melted by the heating block 22, it is extruded from the 3D printing nozzle 23. The controller controls the robotic arm 40 to drive the entire 3D printing device to print the filament along the planned printing path. After printing a section of filament, the pressure control component switches to pressure control mode, causing the impact head 26 to move downwards and press against the molten filament. The filament generates impact and pressure. Depending on the path, the controller can be set to use different but appropriate pressure levels for each path to complete the printing of the shaped part. After printing one layer, the pressure control component switches to displacement control mode, controlling the bottom of the impact head 26 to be higher than the printing plane, and starts printing the next layer. After printing a section of filament, the pressure control component switches to pressure control mode, causing the impact head 26 to move downward and generate impact and pressure on the molten printing filament. This process is repeated layer by layer until the entire printed part is manufactured.

[0034] If the printing path is complex, the 3D printing method is as follows: Start the 3D printing device, switch the pressure control component to displacement control mode, and control the bottom of the impact head 26 to be higher than the printing plane. Begin printing the filament. After printing one layer, stop 3D printing, switch the pressure control component to pressure control mode, and lower the impact head to exert impact and pressure on the molten filament. Depending on the path, different but appropriate pressure levels can be set in the controller for each path to complete the printing of the shaped part. After impact treatment of one layer, switch the pressure control component to displacement control mode, control the bottom of the impact head 26 to be higher than the printing plane, start the 3D printing device, and begin printing the next layer. Repeat this process layer by layer until the entire printed part is manufactured.

[0035] In the description of this invention, it should be noted that the terms "upper", "lower", "left", "right", "inner", "outer", "top / bottom", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0036] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Any simple modifications, equivalent substitutions, and improvements made by those skilled in the art to the above embodiments without departing from the scope of the technical solution of the present invention, based on the technical essence of the present invention, shall still fall within the protection scope of the technical solution of the present invention.

Claims

1. A coaxial pressure ultrasonic impact-assisted 3D printing device, characterized in that, include: The 3D printing nozzle (23), impact head (26), and ultrasonic transducer (27) are configured. The 3D printing nozzle (23) extrudes printing filament along a planned printing path. The impact head (26) moves synchronously with the 3D printing nozzle (23). The impact head (26) has a vertically penetrating conical hole (2601) and a downwardly protruding ring at its bottom end. The ring is coaxially arranged with the conical hole (2601). The 3D printing nozzle (23) is coaxially arranged with the conical hole (2601). The head of the printing nozzle (23) can extend downward through the conical hole (2601) and the ring. The 3D printing nozzle (23) and the impact head (26) do not contact each other. An ultrasonic transducer (27) that can make the impact head (26) vibrate is connected to the impact head (26). A pressure control component that can control the impact head (26) to move up and down along the conical hole (2601) is connected to the ultrasonic transducer (27). The pressure control component controls the impact head (26) to apply appropriate pressure to the surface of the incompletely solidified printing filament.

2. The coaxial pressure ultrasonic impact-assisted 3D printing device according to claim 1, characterized in that: Also includes: The printing support (1), fixing plate one (2), fixing plate two (3), connecting plate (6) and robotic arm (40) are provided. The printing support (1) is fixedly installed at the end of the robotic arm (40). The printing support (1) is provided with a filament threading hole (101) for the printing filament to pass through. The fixing plate one (2) is vertically fixedly installed on the left side of the bottom end of the printing support (1). The fixing plate two (3) is vertically fixedly installed on the rear right side of the printing support (1). The fixing plate one (2) and the fixing plate two (3) are perpendicular to each other. The left end of the fixing plate two (3) is fixedly connected to the connecting plate (6). The left end of the connecting plate (6) is provided with a filament feeding assembly, a water cooling assembly and a heating assembly from top to bottom. The 3D printing nozzle (23) is located at the bottom end of the heating assembly. The pressure control assembly is connected to the fixing plate two (3).

3. The coaxial pressure ultrasonic impact-assisted 3D printing device according to claim 2, characterized in that: Also includes: The rectangular frame (4) and the side plate (5) are arranged symmetrically on the left and right sides. The rectangular frame (4) is located directly below the printing support (1). The front parts of the left and right sides of the rectangular frame (4) are respectively fixedly connected to the lower part of the two side plates (5) facing each other. The upper parts of the two side plates (5) facing each other are respectively fixedly connected to the front left and right sides of the printing support (1). The lower front end of the fixing plate (3) is fixedly connected to the rear side of the rectangular frame (4).

4. The coaxial pressure ultrasonic impact-assisted 3D printing device according to claim 2, characterized in that: The wire feeding assembly includes: a wire feeding motor (7), a motor shaft (8), a wire feeding wheel (9), a hinge shaft (10), an L-shaped pressure plate (11), a pneumatic nozzle (13), a connecting shaft (14), a pressure wheel (15), and a pressure mechanism. The wire feeding motor (7) is fixedly installed on the right end of the first fixed plate (2). The left end of the wire feeding motor (7) is provided with a motor shaft (8). The left end of the motor shaft (8) movably passes through the first fixed plate (2) and the connecting plate (6) respectively, and the wire feeding wheel (9) is coaxially fixedly installed on the left front of the connecting plate (6). The corner of the L-shaped pressure plate (11) is hinged to the upper rear side of the left end of the connecting plate (6) through the hinge shaft (10). The top of the horizontal part of the L-shaped pressure plate (11) is provided with a vertically arranged stepped hole (1101). The pneumatic nozzle (13) is coaxially fixedly installed at the top of the stepped hole (1101). The vertical part of the rear side of the L-shaped pressure plate (11) is rotatably mounted with a pressure wheel (15) through a connecting shaft (14). The pressure wheel (15) is correspondingly arranged with the wire feeding wheel (9). The L-shaped pressure plate (11) is connected to a pressing mechanism for pressing the printing filament between the pressure wheel (15) and the wire feeding wheel (9). The printing filament is fed from the pneumatic nozzle (13) into the stepped hole (1101) and then pressed into contact with the pressure wheel (15) and the wire feeding wheel (9) respectively.

5. The coaxial pressure ultrasonic impact-assisted 3D printing device according to claim 4, characterized in that: The water-cooling assembly includes: a water-cooling block (12), a water inlet (19), and a water outlet (20). The water-cooling block (12) is fixedly installed on the lower left end of the connecting plate (6). The water-cooling block (12) has a stepped hole (1201) for the printing filament to pass through and is vertically arranged. The water-cooling block (12) has a meandering flow channel (1202). The lower front end of the water-cooling block (12) has a water inlet (1203) and a water outlet (1204) arranged sequentially from bottom to top. The water inlet (1203) and the water outlet (1204) are respectively connected to the two ends of the meandering flow channel (1202). The water inlet (19) and the water outlet (20) are respectively installed on the water inlet (1203) and the water outlet (1204).

6. The coaxial pressure ultrasonic impact-assisted 3D printing device according to claim 5, characterized in that: The clamping mechanism includes an upper positioning post (16), a lower positioning post (17), and a spring (18). The upper positioning post (16) is vertically installed through and fixedly mounted on the front side of the horizontal part of the L-shaped pressure plate (11). The lower positioning post (17) is vertically fixedly mounted on the front side of the top end of the water-cooled block (12). The spring (18) is respectively sleeved on the upper positioning post (16) and the lower positioning post (17). The two ends of the spring (18) press against the bottom end of the L-shaped pressure plate (11) and the top end of the water-cooled block (12).

7. The coaxial pressure ultrasonic impact-assisted 3D printing device according to claim 5, characterized in that: Also includes: The throat (21) and the heating assembly include: a heating block (22), an electric heating rod (24) and a temperature sensor (25). The upper part of the throat (21) is coaxially fixedly installed at the lower part of the stepped hole (1201). A vertical through-hole is provided on the heating block (22). The lower part of the throat (21) is coaxially fixedly installed in the through-hole. The 3D printing nozzle (23) is coaxially fixedly installed in the through-hole and is connected to the lower part of the throat (21). The electric heating rod (24) and the temperature sensor (25) are installed sequentially from top to bottom on the left side of the heating block (22).

8. The coaxial pressure ultrasonic impact-assisted 3D printing device according to claim 7, characterized in that: The pressure control assembly includes: clamp one (28), pressure sensor (29), clamp two (30), and a sliding pair. The impact head (26) is composed of a horizontal flat plate section and an inclined cylindrical section. The inclined cylindrical section of the impact head (26) is fixedly connected to the right end of the horizontal flat plate section of the impact head (26) from left to right. The bottom end of the inclined cylindrical section of the impact head (26) is horizontal and flush with the bottom end of the horizontal flat plate section of the impact head (26). The ultrasonic transducer (27) is cylindrical and has a flange section in the middle. The bottom end of the ultrasonic transducer (27) is coaxially fixedly installed on the top end of the inclined cylindrical section of the impact head (26). The clamp one (28) is composed of an inclined flat plate section and a horizontal flat plate section. The inclined flat plate section of the clamp one (28) is fixedly connected to the right end of the horizontal flat plate section of the impact head (26) from left to right. The first clamp (28) is fixedly connected to the left end of the horizontal plate section of the first clamp (28) at an angle from right to left and upward. The inclined plate section of the first clamp (28) has a vertically opened mounting hole. The lower part of the ultrasonic transducer (27) is movably passed through the mounting hole. The flange section of the ultrasonic transducer (27) is fixedly connected to the top of the inclined plate section of the first clamp (28). The second clamp (30) is L-shaped. The horizontal plate section of the second clamp (30) is located directly above the horizontal plate section of the first clamp (28). The pressure sensor (29) is fixedly installed between the horizontal plate section of the first clamp (28) and the horizontal plate section of the second clamp (30). The vertical plate section of the second clamp (30) is connected to the moving end of the sliding pair. The moving end of the sliding pair can move in the vertical direction.

9. The coaxial pressure ultrasonic impact-assisted 3D printing device according to claim 1, characterized in that: The movable pair includes: a fixed base (31), a guide rail (32), a slider (33), a moving block (34), an end plate one (35), an end plate two (36), a stepper motor (37), a screw (38), and a bearing (39). The fixed base (31) is fixedly installed at the front end of the fixed plate two (3). The guide rail (32) is fixedly connected to the middle of the front end of the fixed base (31). The slider (33) is vertically slidably connected to the guide rail (32). The moving block (34) is fixedly connected to the front end of the slider (33). The clamp two (30) The vertical flat plate segment of the fixed base (31) is fixedly connected to the front end of the moving block (34); the upper and lower ends of the fixed base (31) are respectively fixedly installed with end plate one (35) and end plate two (36), the stepper motor (37) is fixedly installed at the top of end plate one (35), the upper end of the screw (38) movably passes through end plate one (35) and is fixedly connected to the output end of the stepper motor (37), the screw (38) vertically passes through and is threadedly connected to the moving block (34), and the lower end of the screw (38) is rotatably installed on end plate two (36) through bearing (39).

10. A coaxial pressure ultrasonic impact-assisted 3D printing method, utilizing the 3D printing apparatus according to any one of claims 1 to 9, characterized in that: The 3D printing method is as follows: The 3D printing device is started, and the printing filament is fed from the pneumatic nozzle (13) into the stepped hole one (1101). Then it is pressed into contact with the pressure roller (15) and the filament feeding roller (9) respectively. Then it passes through the stepped hole two (1201) and the throat tube (21) in the water-cooling block (12) from top to bottom. After being heated and melted by the heating block (22), it is extruded from the 3D printing nozzle (23). The controller controls the robotic arm (40) to drive the entire 3D printing device to print the filament along the planned printing path. After printing a section of filament, the pressure control group... The component switches to pressure control mode, causing the impact head (26) to move downward and exert impact and pressure on the molten printing filament. After printing one layer, the pressure control component switches to displacement control mode, controlling the bottom of the impact head (26) to be higher than the printing plane, and starts printing the next layer. After printing a section of filament, the pressure control component switches to pressure control mode, causing the impact head (26) to move downward and exert impact and pressure on the molten printing filament. This process is repeated layer by layer until the entire printed part is manufactured.

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