Additive manufacturing tool head and additive printer

Abstract

The present application relates to an additive manufacturing tool head and an additive printer. The additive manufacturing tool head comprises a mounting body, a first nozzle, a second nozzle, and a filament channel. The mounting body is provided with an extrusion mechanism, a guide rail mounting portion, a lifting mechanism, the first nozzle, and the second nozzle. The extrusion mechanism comprises an extrusion motor, and the lifting mechanism comprises a lifting motor. The extrusion motor is mounted on a first side of the mounting body and is located above the guide rail mounting portion. The lifting motor is mounted on the first side of the mounting body and is located below the guide rail mounting portion. The tool head further comprises a switching mechanism. The switching mechanism comprises a switching motor, and the switching motor is disposed side-by-side on a side of the extrusion motor. The layout of the extrusion motor, the switching motor, and the lifting motor makes the structure of the tool head compact, the center of gravity stable, and the positioning precise, and greatly improves printing speed and efficiency.

Description

An additive printing tool head and an additive printer

[0001] This application claims priority to PCT patent application PCT / CN2025 / 072614, filed on January 15, 2025, the entire contents of which are incorporated herein by reference. Technical Field

[0002] This application relates to the field of printing technology, and more specifically, to an additive printing toolhead and an additive printer. Background Technology

[0003] In recent years, additive printers have developed rapidly. Among them, additive printers with multiple printheads can meet users' needs for printing color models.

[0004] Dual-head printing assemblies are common printing assemblies, such as US2024 / 0009927A1 and CN115091750B. Both provide a dual-head printing assembly. Driven by a drive mechanism and in conjunction with a transmission structure, the first printhead can move up and down relative to the second printhead. Thus, when the working printhead is in use, the idle printhead will not interfere with or collide with the printed model. At the same time, the extrusion mechanism is driven to switch the extrusion position of the filament to correspond with the first or second printhead.

[0005] In the aforementioned prior art, a single drive mechanism and a complex transmission structure are used to simultaneously drive the extrusion mechanism and the filament switching mechanism, resulting in a large volume of drive mechanism and transmission structure. Since a single drive mechanism is used to drive the lifting and lowering of the print head, the extrusion and switching of the filament, this operation method usually directly acts on the lifting and lowering of the print head, resulting in insufficient flexibility and precision in control. Summary of the Invention

[0006] In view of the above-mentioned technical problems, this application proposes an additive printing tool head and an additive printer, which adopts a reasonable layout of three motors to drive the lifting and lowering of the print head, the extrusion and switching of the filament, thereby improving the accuracy of the motion control of each component, enriching the printing function, and facilitating control and detection, thus achieving a higher degree of automation.

[0007] The additive printing tool head includes a mounting body, a first printhead, a second printhead, and a filament channel. The mounting body is provided with an extrusion mechanism, a guide rail mounting part, a lifting mechanism, the first printhead, and the second printhead. The extrusion mechanism includes an extrusion motor, and the lifting mechanism includes a lifting motor. The extrusion motor is mounted on the first side of the mounting body and is located above the guide rail mounting part, and the lifting motor is mounted on the first side of the mounting body and is located below the guide rail mounting part.

[0008] It also includes a switching mechanism, which includes a switching motor, which is arranged side by side on one side of the extrusion motor.

[0009] The installation body includes a first installation part and a second installation part. The first installation part is at least partially fixed to the upper part of the second installation part. The extrusion mechanism and the switching mechanism are disposed on the first installation part. The lifting mechanism, the first nozzle and the second nozzle are disposed on the second installation part. The guide rail installation part is disposed on the first installation part or the second installation part.

[0010] It also includes a cooling mechanism for cooling the upper part of the first nozzle and the second nozzle and the area below the nozzle, respectively.

[0011] The cooling mechanism includes a first cooling mechanism and a second cooling mechanism, which are used to cool one of the upper part of the first nozzle and the second nozzle and the area below the nozzle, respectively. The first cooling mechanism includes a first fan; the second cooling mechanism includes a second fan; wherein the first fan and the second fan are stacked and located on the side away from the output shaft of the extrusion motor.

[0012] The switching mechanism also includes a switching motor reduction mechanism; the switching motor and the switching motor reduction mechanism are stacked, and the stacked axial height of the switching motor and the switching motor reduction mechanism is flush with or similar to the axial height of the extrusion motor, and the power and size of the extrusion motor are greater than the power and size of the switching motor.

[0013] The linear guide is installed inside the guide rail mounting section and is located in the middle area between the extrusion motor, switching motor, lifting motor, first fan and second fan.

[0014] The tool head is mounted on the linear rail via a guide rail mounting part and can move in the X direction, while the linear rail can move in the Y direction. The switching mechanism also includes a switching motor reduction mechanism, and the lifting mechanism also includes a lifting motor reduction mechanism. The centroid of the tool head's projection in the XY plane or the projection of the tool head's center of gravity in the XY plane coincides with the projection of the linear rail, and / or, at least one of the extrusion motor and the switching motor or the switching motor reduction mechanism, and at least one of the lifting motor or the lifting motor reduction mechanism, all have projections in the XY plane that at least partially overlap with the projection of the linear rail.

[0015] The tool head further includes a control board. The tool head is connected to the additive manufacturing equipment via a cable chain. One end of the cable chain is mounted on the tool head via a cable chain connector. At least a portion of the projections of the first nozzle, the second nozzle, and the wire channel in the XY plane are located on the first side of the projection of the wire rail in the XY plane. At least a portion of the cooling mechanism, the control board, and at least one of the cable chain or cable chain connector are located on the second side of the projection of the wire rail in the XY plane, opposite to the first side.

[0016] The extrusion mechanism also includes an extrusion motor reduction mechanism and an extrusion wheel; the extrusion motor reduction mechanism includes a first reduction gear, which is centrally located on the second side of the mounting body, the second side being the side opposite to the first side; the extrusion wheel and the output shaft of the extrusion motor adopt a single-stage reduction transmission, and the extrusion wheel and the first reduction gear are coaxially arranged.

[0017] The switching motor reduction mechanism is a planetary reduction transmission mechanism.

[0018] The extrusion motor is a permanent magnet synchronous motor.

[0019] The switching mechanism includes a first transmission gear, a second transmission gear, a switching cam, a first swing mechanism, a second swing mechanism, and an elastic element; the switching motor reduction mechanism is connected to the first transmission gear, and the first swing mechanism, the second swing mechanism, and the elastic element are all located on the second side of the mounting body; the first transmission gear and the second transmission gear are meshed together, and the second transmission gear drives the switching cam to swing; the switching cam is centrally located on the mounting body and above the first reduction gear; the first swing mechanism and the second swing mechanism are symmetrically arranged on both sides of the switching cam.

[0020] The first swing mechanism includes a first switching part, a first hinge part, a first pressure roller, and a first swing pivot part arranged sequentially from top to bottom; the second swing mechanism includes a second switching part, a second hinge part, a second pressure roller, and a second swing pivot part arranged sequentially from top to bottom; when the switching cam applies a biasing force to the second switching part, the second switching part moves away from the cam axis, and the first switching part moves towards the cam axis under the action of the elastic element, the second pressure roller moves away from the extrusion roller, and the first pressure roller moves towards the extrusion roller, cooperating to convey the first wire; when the switching cam applies a biasing force to the first switching part, the first switching part moves away from the cam axis, and the second switching part moves towards the cam axis under the action of the elastic element, the first pressure roller moves away from the extrusion roller, and the second pressure roller moves towards the extrusion roller, cooperating to convey the second wire.

[0021] The elastic element has two ends connected to the first hinge and the second hinge, respectively; or, the elastic element includes two elastic elements, the first ends of which are both fixed ends, and the second ends of which are connected to one of the first hinge and the second hinge, respectively.

[0022] The system also includes a first cover, which provides pivot support for at least one of the first swing pivot and the second swing pivot or the extrusion wheel. The first cover is disposed on the second side of the mounting body. A cam positioning block is provided on the switching cam, and a magnetic element is provided on the cam positioning block. A first Hall sensor and a second Hall sensor are provided on the first cover or the mounting body to detect the swing angle of the switching cam or to detect the swing position of the first swing mechanism and the second swing mechanism. A first positioning boss and a second positioning boss are also provided on the first cover or the mounting body to limit the swing range of the cam positioning block.

[0023] The cam positioning block has a trapezoidal structure.

[0024] The magnetic element is a ring magnet. The first Hall sensor and the second Hall sensor are arranged on the first cover or mounting body at a 90° angle to the line connecting them to the cam shaft, and are in the same plane as the ring magnet.

[0025] The ring magnet also has a D-shaped hole.

[0026] The elastic element is a tension spring connected to the first hinge and the second hinge at both ends respectively. When the switching action of the switching cam is in the middle state, the spring tension is large. When the switching cam drives the first switching part or the second switching part to the working position, the spring is in a non-horizontal state and the tension is small.

[0027] The first swing pivot and the second swing pivot are respectively located near the lower ends of the first swing mechanism and the second swing mechanism.

[0028] The second nozzle is fixedly mounted on the second side of the second mounting part and is arranged adjacent to the first nozzle.

[0029] The lifting mechanism includes a drive rocker arm, a drive roller, a drive block, a drive slider, and a drive rail. The drive rocker arm and drive roller are located on the first side of the mounting body. One end of the drive rocker arm is connected to the output shaft of the lifting motor via a drive transmission or direct connection, and the other end is equipped with a drive roller. The drive rail is located on the second side of the mounting body, and the drive slider is slidably mounted on the drive rail. The drive block is located on the first, second, and third sides of the mounting body. The second side is the side opposite to the first side, and the third side is the side connecting the first and second sides. The second sidewall of the drive block on the second side of the mounting body is fixedly connected to the drive slider. A first nozzle is provided on one side of the drive slider, and the first sidewall of the drive block on the first side of the mounting body is provided with a groove that cooperates with the drive roller.

[0030] The slide is a U-shaped slide with a closed side and an open side along the horizontal direction of the drive block. The drive roller can be inserted into the U-shaped slide from the open side. When the lifting motor drives the drive rocker to rotate, the drive roller moves toward the open side of the U-shaped slide, causing the drive block to drive the drive slider to move up and down along the drive slide rail.

[0031] The width of the U-shaped chute in the vertical direction is larger than that of the drive roller, so that the drive roller fits into the upper wall of the U-shaped chute.

[0032] It also includes a limiting part for limiting the range of motion of the drive roller. The limiting part is the groove wall on the closed side of the U-shaped chute; or the limiting part is a protruding structure set on the mounting body or on a structural member fixed relative to the mounting body; or the limiting part is a limiting block set on the gearbox side of the lifting and deceleration mechanism.

[0033] The system also includes a cutting mechanism, which comprises a first cutting mechanism and a second cutting mechanism. The first cutting mechanism includes a first cutting blade, a first cutting blade rod, and a first cutting blade shaft. The second cutting mechanism includes a second cutting blade, a second cutting blade rod, and a second cutting blade shaft. The first and second cutting blade rods are located on the second side of the mounting body and are arranged opposite to each other. The first cutting blade rod is provided with a first cutting blade trigger point, a first cutting blade shaft mounting part, and a first cutting blade mounting part from top to bottom. The second cutting blade rod is provided with a second cutting blade trigger point, a second cutting blade shaft mounting part, and a second cutting blade mounting part from top to bottom. The distance between the first cutting blade trigger point and the first cutting blade shaft mounting part is greater than the distance between the first cutting blade mounting part and the first cutting blade shaft mounting part, and the distance between the second cutting blade trigger point and the second cutting blade shaft mounting part is greater than the distance between the second cutting blade mounting part and the second cutting blade shaft mounting part.

[0034] The first cutter includes a first blade, a first blade holder, and a first pulling rod; the second cutter includes a second blade, a second blade holder, and a second pulling rod. The first blade is disposed inside the first blade holder with its cutting edge facing the first cutter rod, and the second blade is disposed inside the second blade holder with its cutting edge facing the second cutter rod.

[0035] The device includes a guide cover, a follower slider, and a guide rail. The follower slider has a sliding groove on one side and slides in cooperation with the guide rail. The guide rail is mounted on the guide cover, which is at least partially located below the extrusion wheel. The follower slider has a sliding cavity in the horizontal direction, and the first cutter is slidably mounted in the sliding cavity. The first cutter mounting part includes a receiving part that is movably connected to the first pulling protrusion. When the first pulling protrusion is in the first working position, it is located inside the receiving part, and the first cutter can be pulled by the first cutter rod to cut the wire. When the first pulling protrusion is at least in the second working position, it is located outside the receiving part, and the first cutter rod cannot pull the first cutter. The receiving part has an upper opening structure, through which the first pulling protrusion enters or leaves the receiving part.

[0036] It also includes a first guide component and a second guide component, which are fixedly mounted on the guide cover and are used to guide the first wire and the second wire, respectively; the guide cover is also provided with a sliding positioning part, which is used to guide the sliding of the second cutter.

[0037] The follower slider is provided with a sliding channel, and the first guide component slides in conjunction with the sliding channel of the follower slider.

[0038] The first cutter is located between the first cutter shaft and the first nozzle, and the second cutter is located between the second cutter shaft and the second nozzle.

[0039] It also includes a compression spring. The follower slider is provided with a compression spring mounting part. One end of the compression spring is fixed or abuts against the guide cover, and the other end is set in the compression spring mounting part.

[0040] The mounting body has a positioning block positioned opposite the bottom of the drive slider or drive block; the upper surface of the positioning block is flat.

[0041] The center line of the upper surface of the positioning block in the left-right direction is aligned with the center line of the driving slider in the left-right direction.

[0042] A pre-tightening magnetic element is provided on the mounting body at a position opposite to the bottom of the drive block. When the drive block moves downward, the pre-tightening magnetic element generates an attractive force on the drive block. When the drive slider contacts the positioning block, there is a gap between the drive block and the pre-tightening magnetic element.

[0043] The mounting body and the drive slider or the first nozzle are provided with pre-tightening magnetic elements at their relative positions. At least one of the pre-tightening magnetic elements is a magnetic element, and the other is a magnetic element or ferromagnetic material that attracts each other. It is used to apply a downward magnetic attraction force to the drive slider or the first nozzle. When the drive slider or the first nozzle moves downward to the lowest position, there is a gap between the upper surface of the pre-tightening magnetic element and the surface above it that is attracted.

[0044] The second sidewall of the drive block located on the second side of the mounting body is also provided with a metal foil, or the drive block is an aluminum or copper component; on the mounting body, and on the opposite side of the final position of the drive block when it descends, a coil is provided to cooperate with the metal foil or the drive block to detect the degree of sway of the first nozzle; or, the positions of the metal foil and the coil are interchanged.

[0045] The system also includes a nozzle-blocking mechanism, which comprises a swing rod, a nozzle, a positioning magnetic element, a first guiding magnetic element, and a second guiding magnetic element. One end of the swing rod is connected to the output shaft of the lifting motor, and the other end is rotatably connected to the nozzle. The nozzle is provided with a positioning mounting part, on which a positioning magnetic element is installed. The nozzle switches between the first and second nozzles, and the orientation of the nozzle is maintained by the cooperation of the first and second guiding magnetic elements and the positioning magnetic element. The nozzle only blocks the first or second nozzle when it is not in operation.

[0046] The nozzle plugging mechanism further includes an intermediate guiding magnetic element, which is arranged between the first guiding magnetic element and the second guiding magnetic element. It is used to change the orientation of the nozzle when the positioning magnetic element passes the intermediate guiding magnetic element during the switching between the first nozzle and the second nozzle.

[0047] The plug includes a plug mounting base and a plug baffle, with the plug baffle fixedly installed to the plug mounting base.

[0048] Among them, the nozzle baffle is an elastic metal sheet, and the nozzle baffle is provided with an elastic or flexible nozzle layer at the corresponding position of the first and second nozzles. The elastic or flexible nozzle layer is ring-shaped and sleeved on the nozzle baffle.

[0049] The nozzle baffle has a first working position and a second working position, and the first nozzle has an upward limit position and a downward limit position; the first working position of the nozzle baffle corresponds to the upward limit position of the first nozzle, and the second working position of the nozzle baffle corresponds to the second nozzle.

[0050] The lifting motor is provided with a bending plate below it. The bending plate has a first horizontal part, a bending part and a second horizontal part. A first guiding magnetic element is provided on the first horizontal part, a middle guiding magnetic element is inclinedly provided on the bending part, and a second guiding magnetic element is provided on the second horizontal part. The distance between the first guiding magnetic element and the middle guiding magnetic element is greater than the distance between the middle guiding magnetic element and the second guiding magnetic element.

[0051] In the first working position, the positioning magnetic element and the first guiding magnetic element attract each other, and the nozzle baffle is in a horizontal position and blocks the first nozzle. In the second working position, the positioning magnetic element and the second guiding magnetic element attract each other, and the nozzle baffle is in a horizontal position and blocks the second nozzle. When the positioning magnetic element is in a position relative to the middle guiding magnetic element, the nozzle baffle is tilted so that when the nozzle baffle moves to the second working position, it moves at an angle tilted towards the second nozzle.

[0052] The swing rod is a bent rod or an arc rod, and the swing rod bends away from the driving slider.

[0053] The lifting motor drives the first nozzle and the plugging mechanism to move. When the first nozzle begins to descend from the upper limit position, the plugging baffle moves before the first nozzle. When the first nozzle moves from the lower limit position toward the upper limit position, the first nozzle reaches the upper limit position first, and then the plugging baffle reaches the first working position.

[0054] The output shaft of the lifting motor is connected to the first and second transmission shafts via a lifting motor reduction mechanism. The first transmission shaft is used to drive the first nozzle to lift and lower. The second transmission shaft is connected to one end of the swing arm.

[0055] The lifting motor reduction mechanism includes a D-shaped hole or a flat hole, which is connected to a second drive shaft. The second drive shaft is a D-shaped shaft or a flat shaft, and the straight portion of the D-shaped shaft or flat shaft has a gap with the straight portion of the D-shaped hole or flat hole.

[0056] The system includes a fixed frame connected to the mounting body. The first nozzle includes at least one of a first heat dissipation component, a movable hot end, and a first nozzle. The second nozzle includes at least one of a second heat dissipation component, a fixed hot end, and a second nozzle. A first cooling mechanism and a second cooling mechanism are mounted on the fixed frame. The first cooling mechanism includes a first fan housing and a first cooling channel. The second cooling mechanism includes a second fan housing and a second cooling channel. A first fan is installed in the first fan housing and has a first air outlet. A second fan is installed in the second fan housing and has a second air outlet. The first air outlet is connected to the air inlet of the first cooling channel. The air outlet of the first cooling channel is aligned with the first heat dissipation component and the second heat dissipation component. The second air outlet is connected to the air inlet of the second cooling channel and is aligned with the first nozzle and the second nozzle.

[0057] The first nozzle or lifting mechanism is also equipped with a follow-up baffle, which is used to prevent the cooling air blown out of the first cooling channel from blowing towards the heating area of ​​the first nozzle at the upper limit position of the first nozzle.

[0058] The follow-up baffle has a body portion, which is installed on the side of the heating area of ​​the first nozzle. When the first nozzle is at its maximum rising position, the body portion blocks a portion of the opening of the first cooling channel to prevent cooling air from blowing toward the heating area of ​​the first nozzle.

[0059] The follow-up baffle also has a bending portion, which is located at the upper edge of the main body and bends toward the first heat dissipation component; when the first nozzle is at the upper limit position, the cooling air is guided by the bending portion and blown toward the first heat dissipation component.

[0060] The follow-up baffle is installed on the side of the heating area of ​​the first nozzle and has a guide plate facing the first heat dissipation component. When the first nozzle is at its upper limit position, the opening of the first cooling channel faces the guide plate, so that the cooling air is blown towards the first heat dissipation component through the guide plate, thereby preventing the cooling air from blowing towards the heating area of ​​the first nozzle.

[0061] The cooling mechanism includes a cooling fan, a first cooling channel and a second cooling channel. The air outlet of the first cooling channel is aligned with the first heat dissipation component and the second heat dissipation component, and the air outlet of the second cooling channel is aligned with the first nozzle and the second nozzle.

[0062] Both the first and second cooling channels are equipped with flow guiding structures.

[0063] The first fan housing cavity has a first air inlet, which corresponds to the extrusion motor; the second fan housing cavity has a second air inlet on both the inner and outer sides, with the inner second air inlet corresponding to the circuit board of the printing tool head, and the outer second air inlet connecting to the external environment.

[0064] It also includes a nozzle camera and a workbench camera. The nozzle camera is located in the middle area of ​​the first cooling channel or the second cooling channel, and the workbench camera is located on the outside of the first cooling channel or the second cooling channel.

[0065] It also includes a cable fixing structure, which is fixed relative to the first nozzle or the lifting mechanism. The cable extending from the first nozzle is fixed by the cable fixing structure. The cable has a connector, which is located between the first nozzle and the position where the cable fixing structure fixes the cable.

[0066] The tool head housing has a function expansion slot for installing function expansion accessories, which are located at the front of the housing.

[0067] This application also provides an additive printer that uses the additive printing toolhead described above.

[0068] Other beneficial effects of this application will be explained in detail through the introduction of specific technical features and technical solutions in the specific embodiments. Those skilled in the art should be able to understand the beneficial technical effects brought about by the technical features and technical solutions through the introduction of these technical features and technical solutions. Attached Figure Description

[0069] The preferred embodiments of this application will now be described with reference to the accompanying drawings.

[0070] Figure 1 is a schematic diagram of the motor layout of an additive printing tool head according to this application;

[0071] Figure 2 is a front view of an additive printing tool head according to this application;

[0072] Figure 3 is a schematic diagram of the first fan of an additive printing tool head according to this application;

[0073] Figure 4 is a schematic diagram of the second cooling mechanism of an additive printing tool head according to this application;

[0074] Figure 5 is a side view of an additive printing tool head according to this application;

[0075] Figure 6 is a schematic diagram of the overall layout of an additive printing tool head according to this application;

[0076] Figure 7 is an exploded view of the overall structure of an additive printing tool head according to this application;

[0077] Figure 8 is a schematic diagram of an extrusion and switching mechanism for an additive printing tool head according to this application;

[0078] Figure 9 is a front view of the extrusion and switching mechanism of an additive printing tool head according to this application;

[0079] Figures 10a, 10b, and 10c are schematic diagrams of the operation of a switching mechanism for an additive printing tool head according to this application;

[0080] Figure 11 is an exploded view of the extrusion mechanism, switching mechanism, and cutting mechanism of an additive printing tool head according to this application;

[0081] Figure 12 is a schematic diagram of the first side wall of the drive block of the lifting mechanism of an additive printing tool head according to this application;

[0082] Figure 13 is a schematic diagram of the third side of the drive block of the lifting mechanism of an additive printing tool head according to this application;

[0083] Figure 14 is a schematic diagram of the second sidewall of the drive block of an additive printing tool head according to this application and its lifting transmission with the first nozzle;

[0084] Figure 15 is a front view of an extrusion, switching and cutting mechanism of an additive printing tool head according to this application;

[0085] Figure 16 is a schematic diagram of the first cutter mechanism of an additive printing tool head in the working position according to this application;

[0086] Figure 17 is a schematic diagram of the first cutting mechanism of an additive printing tool head according to this application;

[0087] Figure 18 is a schematic diagram of the first cutter mechanism of an additive printing tool head in the non-working position according to this application;

[0088] Figure 19 is a schematic diagram of the inner structure of the first cover and the material guide cover of an additive printing tool head according to this application;

[0089] Figure 20 is a partial schematic diagram of a lifting mechanism for an additive printing tool head according to this application;

[0090] Figure 21 is a schematic diagram of the drive block of the lifting mechanism of an additive printing tool head according to this application;

[0091] Figure 22 is a schematic diagram of the metal foil coil of the lifting mechanism of an additive printing tool head according to this application;

[0092] Figure 23 is a schematic diagram of the lifting motor reduction mechanism and the nozzle plugging mechanism of an additive printing tool head according to this application;

[0093] Figure 24 is a schematic diagram of a nozzle-blocking mechanism for an additive printing tool head according to this application, which blocks the second nozzle.

[0094] Figure 25 is a schematic diagram of the sealing movement process of the plugging mechanism of an additive printing tool head according to this application;

[0095] Figure 26 is a schematic diagram of a nozzle-blocking mechanism for an additive printing tool head according to this application, which blocks the first nozzle.

[0096] Figure 27 is a schematic diagram of the lowering position of the drive block of the lifting mechanism of an additive printing tool head according to this application;

[0097] Figure 28 is a schematic diagram of the intermediate state of the drive block rising and falling in the lifting mechanism of an additive printing tool head according to this application;

[0098] Figure 29 is a schematic diagram of the rising position of the drive block of the lifting mechanism of an additive printing tool head according to this application;

[0099] Figure 30 is a top view of a limiting component and a wire limiting mechanism for an additive printing tool head according to this application;

[0100] Figure 31 is a schematic diagram of a limiting component and a wire limiting mechanism for an additive printing tool head according to this application;

[0101] Figure 32 is a partial schematic diagram of the first limiting member and the first wire limiting mechanism of an additive printing tool head according to this application;

[0102] Figure 33 is a partial schematic diagram of the second limiting member of an additive printing tool head according to this application;

[0103] Figure 34 is a partial schematic diagram of the first limiting member of an additive printing tool head according to this application;

[0104] Figure 35 is a partial schematic diagram of a wire limiting mechanism for an additive printing tool head according to this application;

[0105] Figure 36 is a schematic diagram of the positioning block and Hall element of an additive printing tool head according to this application;

[0106] Figure 37 is a schematic diagram of a cable fixing structure and a follower baffle of an additive printing tool head according to this application;

[0107] Figure 38 is a partially enlarged schematic diagram of the cable fixing structure and the follower baffle in Figure 37;

[0108] Figure 39 is a partially enlarged schematic diagram of the driving block in Figure 29;

[0109] Figure 40 is a schematic diagram of one working state of the follower baffle in Figure 37;

[0110] Figure 41 is a schematic diagram of another working state of the follower baffle in Figure 37. Detailed Implementation

[0111] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0112] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0113] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0114] It should be noted that when an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. When an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0115] Regarding the prior art mentioned in the background section, after extensive experimentation and analysis, this application has also identified the following further technical problems:

[0116] The current operating method often results in the filament in the print head that has finished printing being squeezed out and moved when one print head finishes its job and switches to another print head. This can cause unwanted nozzle material to overflow from the print head that has finished printing.

[0117] Furthermore, the undesirable overflow of filaments and the accidental overflow of filaments from a printhead in a non-working state can affect the ongoing printing process. How to avoid the impact of the overflowing filaments on printing is a technical problem that urgently needs to be solved.

[0118] Furthermore, the arrangement of the extrusion mechanism, switching mechanism, cutting mechanism, lifting mechanism, and cooling mechanism of the tool head in the existing technology is not compact enough, and the force applied by each mechanism component is not optimized, resulting in a large tool head size and the fact that the cutter can be removed, which may cause safety issues.

[0119] In addition, when one of the wires in the tool head of the prior art is not in working condition, the wire may be pulled as the tool head moves, which may lead to inaccurate control of the next flush volume of the nozzle, or may pull some melted but not completely solidified wire into the throat of the hot end and block the nozzle.

[0120] The existing tool head lifting nozzle's movable hot end still has the problem of low heat dissipation efficiency. If the air outlet is aimed at the position where the movable hot end is below, there will be a misalignment between the air outlet and the heat sink of the movable hot end when the movable hot end is above, meaning that some air will not reach the heat sink.

[0121] Based on the discovery of the above-mentioned technical problems, this application proposes a series of technical solutions to solve the problems of the prior art discovered in this application one by one.

[0122] Layout of the tool head components and extrusion mechanism

[0123] As shown in Figures 1-7, the additive printing tool head of this application includes a mounting body, a first printhead 51, a second printhead 52, and a filament channel. The mounting body is equipped with an extrusion mechanism 3, a guide rail mounting part 101, a lifting mechanism 5, the first printhead 51, and the second printhead 52. The extrusion mechanism 3 includes an extrusion motor 301, and the lifting mechanism 5 includes a lifting motor 501. The extrusion motor 301 is mounted on the first side of the mounting body and located above the guide rail mounting part 101, while the lifting motor 501 is mounted on the first side of the mounting body and located below the guide rail mounting part 101. The application also includes a switching mechanism 4, which includes a switching motor 401, arranged side-by-side on one side of the extrusion motor 301. The separately configured extrusion motor, lifting motor, and switching motor execute actions according to control commands, effectively preventing interference between printhead lifting, filament extrusion, and switching operations. This prevents unwanted filament overflow from printheads that have finished printing, and decouples the lifting, filament extrusion, and switching operations, allowing for independent control and monitoring of different processes. This improves the automation level of the equipment and enables more functions. The extrusion motor is located above the guide rail mounting section, while the lifting motor is below. This ensures the lifting motor is closer to the printhead, shortening the transmission chain, improving transmission accuracy, reducing the size of transmission components, and balancing the tool head's center of gravity, minimizing "nodding" deformation when moving along the guide rail.

[0124] The mounting body includes a first mounting part 1 and a second mounting part 2. The first mounting part 1 is at least partially fixed to the upper part of the second mounting part 2. The extrusion mechanism 3 and the switching mechanism 4 are disposed on the first mounting part 1, and the lifting mechanism 5, the first nozzle 51, and the second nozzle 52 are disposed on the second mounting part 2. The guide rail mounting part 101 is disposed on either the first mounting part 1 or the second mounting part 2. The mounting body can be manufactured as a single piece or constructed by connecting multiple parts. It is used to support the various components of the tool head. For example, a high-strength metal mounting body can be formed by integral die casting, and the installation positions of each component can be precisely machined through subtractive manufacturing. This can achieve a shorter relative positional dimension chain of each component, thereby improving the installation accuracy.

[0125] The switching mechanism 4 also includes a switching motor reduction mechanism 402. The switching motor 401 and the switching motor reduction mechanism 402 are stacked, with their stacked axial height being flush with or similar to the axial height of the extrusion motor 301. The power and size of the extrusion motor 301 are greater than those of the switching motor 401. The switching motor reduction mechanism 402 is a planetary reduction transmission mechanism, such as a double planetary reducer. The extrusion motor 301 is a permanent magnet synchronous motor. In this layout, the extrusion motor can use a relatively large size and operating power, enabling high-speed filament extrusion, thereby improving printing speed and efficiency. The switching motor is smaller, and the use of a planetary reducer ensures that the stacked axial height of the switching motor 401 and the switching motor reduction mechanism 402 is flush with or similar to the height of the extrusion motor, thus preventing the print head size from undesirably increasing due to the increased number of motors.

[0126] One or more linear guides are installed in the guide rail mounting part 101 and are located in the middle area of ​​the extrusion motor 301, the switching motor 401, the lifting motor 501, the first fan 601 and the second fan 701. The tool head is mounted on the linear rail via a guide rail mounting part and can move in the X direction, while the linear rail can move in the Y direction. The switching mechanism 4 also includes a switching motor reduction mechanism 402, and the lifting mechanism 5 also includes a lifting motor reduction mechanism 507. The centroid of the tool head's projection in the XY plane or the projection of the tool head's center of gravity in the XY plane coincides with the projection of the linear rail, and / or, at least one of the extrusion motor 301 and the switching motor 401 or the switching motor reduction mechanism 402, and at least one of the lifting motor 501 or the lifting motor reduction mechanism, all have projections in the XY plane that at least partially overlap with the projection of the linear rail. It is understood that the extrusion motor 301 and the switching motor 401 or the switching motor reduction mechanism 402 have high mass, which has a significant impact on the centroid distribution of the tool head. By distributing the motors up and down around the linear rail, the centroid of the tool head is closer to the linear rail in the height direction, thereby reducing the acceleration and deceleration torque of the tool head in the Y-axis direction, reducing the nozzle deformation introduced during the processing motion, and thus improving the printing quality.

[0127] When there are two or more linear guides, the centroid of the tool head's projection in the XY plane, or the center of gravity of the tool head, is located in the area between at least the two outermost linear guides. The tool head also includes a control board. The tool head is connected to the additive manufacturing equipment via a cable chain. One end of the cable chain is mounted to the tool head via a cable chain connector. The cable chain carries the connecting wires such as feed pipes and cables between the tool head and the additive manufacturing equipment. At least a portion of the projections of the first nozzle 51, the second nozzle 52, and the wire channel in the XY plane are located on the first side of the linear guide's projection in the XY plane. At least a portion of the cooling mechanism, the control board, and at least one of the cable chain or cable chain connector have projections in the XY plane located on the second side of the linear guide's projection in the XY plane, opposite to the first side. This arrangement ensures that the components surround the linear guides, guaranteeing a stable center of gravity, stable operation, and high overall strength for the tool head. In this application, the linear guide can be fixedly installed on the support profile, which can move together with the linear guide along the Y direction. When referring to the projection of the linear guide, it can refer to the projection of the whole formed by the support profile and the linear guide, or more precisely, the projection of the linear guide on the support profile.

[0128] The extrusion mechanism includes an extrusion motor reduction mechanism 302 and an extrusion wheel 303. The extrusion motor reduction mechanism 302 includes a first reduction gear 304, which is centrally located on the second side of the mounting body, opposite to the first side. The extrusion wheel 303 and the output shaft of the extrusion motor are connected by a single-stage reduction transmission, and the extrusion wheel 303 and the first reduction gear 304 are coaxially arranged. The diameter of the extrusion wheel can be set to match the position of the wire channel, ensuring that the wire is transported as straight as possible. The extrusion motor is distributed on both sides of the centerline of the mounting body through transmission gears, which can fully utilize the installation space of the tool head, allowing for a larger size of the extrusion motor's reduction gears, thereby achieving greater driving force and single-stage reduction. The single-stage reduction transmission between the extrusion motor's reduction gears and the extrusion motor effectively reduces the number of gear transmission stages, improves transmission accuracy, facilitates closed-loop control, and thus has greater power and extrusion speed, enabling high-speed printing.

[0129] The second nozzle 52 is fixedly disposed on the second side of the second mounting part 2 and is disposed adjacent to the first nozzle 51.

[0130] Switching mechanism

[0131] As shown in Figures 8-11 and 36, the switching mechanism 4 includes a switching motor 401, a switching motor reduction mechanism 402, a first transmission gear 403, a second transmission gear 404, a switching cam 405, a first swing mechanism 406, a second swing mechanism 407, and an elastic element 408. The switching motor reduction mechanism 402 is connected to the first transmission gear 403. The first swing mechanism 406, the second swing mechanism 407, and the elastic element 408 are all located on the second side of the mounting body. The first transmission gear 403 is meshed with the second transmission gear 404, and the second transmission gear 404 drives the switching cam 405 to swing. The switching cam 405 is centrally located on the mounting body and above the first reduction gear 304. The first swing mechanism 406 and the second swing mechanism 407 are symmetrically arranged on both sides of the switching cam 405. The first swing mechanism 406 includes a first switching part 411, a first pressure roller 413, and a first swing pivot part 414 arranged sequentially from top to bottom; the second swing mechanism 407 includes a second switching part 421, a second pressure roller 423, and a second swing pivot part 424 arranged sequentially from top to bottom; when the switching cam 405 applies a biasing force to the second switching part 421, the second switching part 421 moves away from the cam axis, and the first switching part 411 moves towards the cam axis under the action of the elastic element 408, the second pressure roller 423 moves away from the extrusion roller 303, and the first pressure roller 413 moves towards the extrusion roller 303, cooperating to transport the first wire; when the switching cam 405 applies a biasing force to the first switching part 411, the first switching part 411 moves away from the cam axis, and the second switching part 421 moves towards the cam axis under the action of the elastic element 408, the first pressure roller 413 moves away from the extrusion roller 303, and the second pressure roller 423 moves towards the extrusion roller 303, cooperating to transport the second wire.

[0132] The first swing pivot 414 and the second swing pivot 424 are respectively located near the lower ends of the first swing mechanism 406 and the second swing mechanism 407. The switching cam is located at the upper end, while the swing pivot is located at the lower end. The switching cam is positioned away from the swing pivot, which ensures that the bias force between the switching cam and the switching part is small, thereby reducing the wear of the cam and improving its service life.

[0133] Along the top-to-bottom direction of the first swing mechanism 406, a first hinge portion 412 is provided between the first switching portion 411 and the first pressure roller 413; along the top-to-bottom direction of the second swing mechanism 407, a second hinge portion 422 is provided between the second switching portion 421 and the second pressure roller 423; the first swing mechanism 406 and the second swing mechanism 407 are symmetrically arranged on both sides of the switching cam 405. The two ends of the elastic element 408 are respectively connected to the first hinge portion 412 and the second hinge portion 422; or, the elastic element 408 includes two elastic elements, the first ends of which are both fixed ends, and the second ends are respectively connected to one of the first hinge portion 412 and the second hinge portion 422. The elastic element 408 is a tension spring connected at both ends to the first hinge portion 412 and the second hinge portion 422 respectively. In the intermediate state of the switching action of the switching cam 405, the spring tension is relatively large. When the switching cam 405 drives the first switching portion 411 or the second switching portion 421 to the working position, the spring is in a non-horizontal state and the tension is relatively small. Thus, the first switching portion 411 or the second switching portion 421 can have a bistable position in the working positions on both sides, and an unstable position in the intermediate state, which helps improve the reliability of the switching action. It should be noted that the extrusion wheel is centrally located, and the two switching portions are symmetrically arranged on both sides of the extrusion wheel. More specifically, the extrusion wheel 303 is located between the first swing pivot portion 414, the second swing pivot portion 424, and the elastic element 408, and the switching cam is located above the extrusion wheel, allowing for a reasonable arrangement of the tool head space. The two swing mechanisms are identical in shape and symmetrically arranged. When in the working position on either side, the spring is in a non-horizontal state, and the spring force is less than the spring force when the connection point of the two springs is in a horizontal state. This can form a "bistable" switching, which is beneficial to improving the reliability of the switching action.

[0134] Since the distance between the elastic element and the pivot is greater than the distance between the extrusion wheel and the pivot, the force acting on the extrusion wheel will be greater than the tension of the elastic element. This allows the size of the elastic element to be set smaller, which is beneficial for miniaturization and weight reduction of the tool head.

[0135] It also includes a first cover 11, which provides pivot support for at least one of the first swing pivot 414 and the second swing pivot 424 or the extrusion wheel. The first cover 11 is disposed on the second side of the mounting body. A cam positioning block 409 is provided on the switching cam 405, and a magnetic element 4091 is provided on the cam positioning block 409. A first Hall sensor 4092 and a second Hall sensor 4093 (see FIG. 36) are provided on the first cover or the mounting body (e.g., the first mounting part) to detect the swing angle of the switching cam 405 or to detect the swing position of the first swing mechanism 406 and the second swing mechanism 407. A first positioning boss 111 and a second positioning boss 112 are also provided on the first cover 11 or the mounting body (e.g., the first mounting part) to limit the swing range of the cam positioning block 409. The cam positioning block 409 has a trapezoidal structure. The magnetic element 4091 is a ring magnet. The first Hall sensor 4092 and the second Hall sensor 4093 are arranged on the first cover 11 or the mounting body at a 90° angle to the line connecting the cam shaft, and are in the same plane as the ring magnet. The ring magnet also has a D-shaped hole. The switching cam cooperates with the switching parts of the swing mechanism on the left and right sides. The plane of the trapezoidal positioning block, which is coaxial with the switching cam, contacts the positioning boss on the first cover to form a limit and position. The switching cam and the trapezoidal positioning block can be integrally formed. A magnet can be set on the outside of the trapezoidal positioning block. Hall sensors arranged at right angles are provided on the first cover at the corresponding positions of the magnets to detect the position angle of the switching cam.

[0136] As shown in Figures 30-35, the wire channel includes a first wire channel and a second wire channel; the switching mechanism and the extrusion mechanism cooperate to allow the first wire in the first wire channel and the second wire in the second wire channel to work alternately; it also includes a first cover 11, which is disposed on the mounting body; the first cover 11 is provided with a first limiting member 431 and a second limiting member 432; the first swing mechanism 406 is provided with a first wire limiting mechanism 441, and the second swing mechanism 407 is provided with a second wire limiting mechanism 442; when the first wire channel is in at least one non-working position, the first limiting member 431 cooperates with the first wire limiting mechanism 441 to restrict the upward movement of the first wire in the first wire channel; when the second wire channel is in at least one non-working position, the second limiting member 432 cooperates with the second wire limiting mechanism 442 to restrict the upward movement of the second wire in the second wire channel. The first limiting member 431 includes a first steel ball 4311 and a first mounting groove 4313; the second limiting member 432 includes a second steel ball 4321 and a second mounting groove 4323; or, the first limiting member 431 includes a protrusion or abutment on the first cover, and the second limiting member 432 includes a protrusion or abutment on the first cover. The first wire limiting mechanism 441 includes a first movable limiting member 4411 and a first limiting structure 4412; the second wire limiting mechanism 442 includes a second movable limiting member 4421 and a second limiting structure 4422. The first movable limiting member 4411 and the first limiting structure 4412 can be integrally formed or separately formed; the second movable limiting member 4421 and the second limiting structure 4422 can be integrally formed or separately formed. The first mounting groove 4313 and the second mounting groove 4323 are disposed on the first cover 11; the first limiting member 431 is disposed opposite to the first wire channel, and the second limiting member 432 is disposed opposite to the second wire channel; the first wire limiting mechanism 441 is disposed on the first swing mechanism 406, and the second wire limiting mechanism 442 is disposed on the second swing mechanism 407; when the first wire channel is at the end position of the non-working state, the first limiting member 431 abuts against the first wire limiting mechanism 441; when the second wire channel is at the end position of the non-working state, the second limiting member 432 abuts against the second wire limiting mechanism 442. When the first wire channel or the second wire channel is in the working state, the first wire limiting mechanism 441 or the second wire limiting mechanism 442 returns to the position that does not restrict the upward movement of the wire under the action of the wire or elastic element.

[0137] Specifically, the first limiting structure 4412 or the second limiting structure 4422 is a cutting edge, tip, protrusion, or other structure disposed at the end of the first movable limiting member 4411 or the second movable limiting member 4421, capable of engaging the wire, used to restrict the upward movement of the wire at the end position in the non-working state. In one embodiment, the first limiting structure 4412 or the second limiting structure 4422 is a one-way limiting structure. Specifically, the first limiting structure 4412 and the second limiting structure 4422 are downwardly extending tooth-like, hook-like, or claw-like structures. The first limiting structure 4412 or the second limiting structure 4422 has a slope or arc surface and a cutting edge or tip for engaging the wire. When the wire moves from top to bottom, it can act on the slope or arc surface, causing the one-way limiting structure to move away from the wire. When the wire moves from bottom to top, the wire is engaged by the cutting edge or tip for engaging the wire, restricting its movement.

[0138] It also includes a first elastic mechanism 4312 and a second elastic mechanism 4322. One end of the first elastic mechanism 4312 is disposed in the first mounting groove 4313, and the other end is connected to a first steel ball 4311. One end of the second elastic mechanism 4322 is disposed in the second mounting groove 4323, and the other end is connected to a second steel ball 4321. The first steel ball 4311 and the second steel ball 4321 both protrude at least partially from the first mounting groove 4313 and the second steel ball 4321, respectively. When the first wire channel is in at least one non-working position, the first steel ball 4311 abuts against the first movable limiting member 4411, causing the first limiting structure 4412 to at least partially enter the first wire channel and compress the first wire. When the second wire channel is in at least one non-working position, the second steel ball 4321 abuts against the second movable limiting member 4421, causing the second limiting structure 4422 to at least partially enter the second wire channel and compress the second wire. The first elastic mechanism 4312 and the second elastic mechanism 4322 are springs. By setting an elastic mechanism, the force applied during the pushing process can be made gentler, reducing the chance of jamming and increasing the service life of the first wire limiting mechanism 441 or the second wire limiting mechanism 442.

[0139] It also includes a first elastic reset member 4413 disposed on the first swing mechanism 406, and a second elastic reset member 4423 disposed on the second swing mechanism 407; one end of the first elastic reset member 4413 is connected to the first movable limiting member 4411, and the other end is connected to the first swing mechanism 406. When the first wire channel is in the working state or between the working state and the end position of the non-working state, the first movable limiting member 4411 moves away from the wire under the action of the first elastic reset member 4413; one end of the second elastic reset member 4423 is connected to the second movable limiting member 4421, and the other end is connected to the second swing mechanism 407. When the second wire channel is in the working state or between the working state and the end position of the non-working state, the second movable limiting member 4421 moves away from the wire under the action of the second elastic reset member 4423.

[0140] It should be noted that, through the limiting function of the wire limiting mechanism, the wire in the non-working state will be reliably fixed and will not be pulled by external forces (such as tool head movement, wire guide tube shaking, etc.). This avoids inaccurate control of the spray volume in the next spray and also prevents the problem of some melted but not completely solidified wire being pulled into the throat of the hot end and thus clogging the spray head.

[0141] Lifting mechanism

[0142] As shown in Figures 12-14, 19-23, and 36, the lifting mechanism 5 includes a lifting motor 501, a drive rocker arm 502, a drive roller 503, a drive block 504, a drive slider 505, a drive slide rail 506, and a lifting motor reduction mechanism 507. The drive rocker arm 502 and the drive roller 503 are located on the first side of the mounting body. One end of the drive rocker arm 502 is connected to the output shaft of the lifting motor 501 via a transmission connection or direct connection, and the other end is provided with the drive roller 503. The drive slide rail 506 is located on the second side of the mounting body, and the drive slider 505 is slidably mounted on the drive slide rail 506. 6. The drive block 504 has a U-shaped, I-shaped, or square-shaped cross-section and is provided on at least the first, second, and third sides of the mounting body. The second side is the side opposite to the first side, and the third side is the side connecting the first and second sides. The second sidewall 5041 of the drive block 504 on the second side of the mounting body is fixedly connected to the drive slider 505. A first nozzle 51 is provided on one side of the drive slider 505. A groove is provided on the first sidewall 5042 of the drive block 504 on the first side of the mounting body. The groove is preferably a U-shaped groove 5043, which cooperates with the drive roller 503. The U-shaped slide 5043 has a closed side and an open side along the horizontal direction of the drive block 504. The drive roller 503 can be inserted into the U-shaped slide 5043 from the open side. When the lifting motor 501 drives the drive rocker arm 502 to rotate, the drive roller 503 moves towards the open side of the U-shaped slide 5043, causing the drive block 504 to drive the drive slider 505 to move up and down along the drive rail 506. The width of the U-shaped slide 5043 in the vertical direction is larger than the size of the drive roller 503, so that the drive roller 503 fits with the upper wall of the U-shaped slide 5043. Preferably, the closed side of the U-shaped slide 5043 has a self-locking angle of 5°-15°. The U-shaped slide is slightly larger than the drive roller, so that the drive roller can be inserted into the U-shaped slide from the open side during assembly, which is convenient for assembly. The rotation angle of the drive roller can be 200°, meaning it will rotate an additional 5° or 10° in both the up and down positions to achieve self-locking. In another embodiment, the U-shaped chute can be replaced with a closed chute without an open side. In this embodiment, except that the open side of the U-shaped chute is set to be closed, the cooperation method between the chute and the drive roller and the working process are the same as in the embodiment of the U-shaped chute.

[0143] It also includes a limiting part for limiting the range of motion of the drive roller. The limiting part is the groove wall on the closed side of the U-shaped chute; or the limiting part is a protruding structure set on the mounting body or on a structural member fixed relative to the mounting body; or the limiting part is a limiting block set on the gearbox side of the lifting and deceleration mechanism.

[0144] Referring to Figure 36, a positioning block 5051 is provided on the mounting body at a position opposite to the bottom of the drive slider 505 or drive block 504. The upper surface of the positioning block 5051 is a plane, preferably a finely ground plane. In one embodiment, the positioning block 5051 is a screw, which coincides with the central axis of the drive slider 505. The center line of the upper surface of the positioning block 5051 in the left-right direction is aligned with the center line of the drive slider 505 in the left-right direction. Matching pairs of pre-tightening magnetic elements 5052 are provided at relative positions on the mounting body and the drive slider 505 or drive block 504 (or the first nozzle 51). At least one of the pre-tightening magnetic elements 5052 is a magnetic element, and the other is a mutually attracting magnetic element or a ferromagnetic material. When the drive block moves downward, the pre-tightening magnetic element 5052 applies a downward magnetic attraction force to the drive slider 505 or the drive block 504 (or the first nozzle 51). When the drive slider 505 contacts the positioning block 5051 or when the drive block 504 moves downward to its lowest position, there is a gap between the drive block 504 and the pre-tightening magnetic element 5052. The magnetic attraction force is to provide a positioning force to prevent the nozzle from shifting due to scratches or other reasons.

[0145] The drive block 504, located on the first sidewall 5042 of the first side of the mounting body, is also provided with a metal foil 5044, such as copper foil, aluminum foil, or iron foil, with copper foil being the most preferred. On the mounting body, on the opposite side of the final descending position of the drive block 504, a coil 5045 is provided to cooperate with the metal foil 5044 to detect the degree of sway of the first nozzle 51; alternatively, the positions of the metal foil 5044 and the coil 5045 can be interchanged. The metal foil and coil cooperate to detect whether the first nozzle is in position.

[0146] Alternatively, the drive block 504 itself can be made of aluminum or copper. In this case, there is no need to set the metal foil 5044. The coil 5045 can cooperate with the drive block 504 to detect the degree of sway of the first nozzle 51.

[0147] As shown in Figure 23, the lifting motor reduction mechanism includes: gear one, gear two, gear three, gear four, gear five, gear shaft, and sector gear. Gear one is mounted on the output shaft of the lifting motor and meshes with gear two. Gear two is mounted on a gear shaft, and gear three is mounted on the gear shaft coaxially with gear two. Gear three meshes with gear four. Gear four is mounted on a first transmission shaft 5071, and gear five is mounted on the first transmission shaft 5071 coaxially with gear four. Gears one to five are for reduction transmission. Gear five meshes with sector gear, and a second transmission shaft 5072 is mounted on sector gear.

[0148] The second drive shaft 5072 is used to drive the movement of the plugging mechanism, which will be described later. The lifting electrode reduction mechanism includes a lifting reduction gearbox, on the outside of which a pair of Hall sensors can be mounted. The pair of Hall sensors are arranged at 90° with the axis of the second drive shaft 5072 as the center. At the same time, magnets are arranged on the sector gear. By cooperating with the Hall sensors, the working state of the plugging mechanism or the lifting mechanism can be detected, such as the rotation angle of the plugging rod, which will be mentioned later.

[0149] As shown in Figures 37-38, the system also includes a cable fixing structure 16, which is fixed relative to the first nozzle 51 or the lifting mechanism. The cable extending from the first nozzle 51 is fixed by the cable fixing structure 16. The cable has a connector located between the first nozzle 51 and the position where the cable fixing structure 16 fixes the cable. Preferably, the cable fixing structure is a plate-like structure with a cable receiving portion 161 at its lower end for fixing the cable. The cable receiving portion 161 has an opening 162 for placing the cable into it. During the lifting and lowering process of the first nozzle 51, the cable fixing structure 16 remains fixed relative to the first nozzle 51, with no relative displacement between them. Therefore, the cable connector is not subjected to external force pulling caused by the lifting and lowering process, thus preventing the connector from loosening and ensuring reliability.

[0150] Cutting mechanism

[0151] As shown in Figures 15-19, the cutting mechanism includes a first cutting mechanism 81 and a second cutting mechanism 82; the first cutting mechanism includes a first cutting blade 811, a first cutting blade rod 812, and a first cutting blade shaft 813; the second cutting mechanism 82 includes a second cutting blade 821, a second cutting blade rod 822, and a second cutting blade shaft 823; a first swing pivot 414 is disposed adjacent to the first cutting blade shaft 813; and a second swing pivot 424 is disposed adjacent to the second cutting blade shaft 823. The first cutting bar 812 and the second cutting bar 822 are located on the second side of the mounting body, and are arranged opposite to each other. The first cutting bar 812 is provided with a first cutting trigger point 8121, a first cutting shaft mounting part 8122, and a first cutting mounting part 8123 in sequence from top to bottom. The second cutting bar 822 is provided with a second cutting trigger point 8221, a second cutting shaft mounting part 8222, and a second cutting mounting part 8223 in sequence from top to bottom. The distance between the first cutting trigger point 8121 and the first cutting shaft mounting part 8122 is greater than the distance between the first cutting shaft mounting part 8123 and the first cutting shaft mounting part 8122, and the distance between the second cutting trigger point 8221 and the second cutting shaft mounting part 8222 is greater than the distance between the second cutting shaft mounting part 8223 and the second cutting shaft mounting part 8222. The first cutter 811 includes a first blade 8111, a first blade holder 8112, and a first pulling rod 8113. The second cutter 821 includes a second blade 8211, a second blade holder 8212, and a second pulling rod 8213. The first blade 8111 is disposed inside the first blade holder 8112, with its cutting edge facing the first cutter rod 812. The second blade 8211 is disposed inside the second blade holder 8212, with its cutting edge facing the second cutter rod 822. The first cutter is located between the first cutter shaft and the first nozzle, and the second cutter is located between the second cutter shaft and the second nozzle. It should be noted that in the layout of the extrusion mechanism, switching mechanism, and cutting mechanism in this application, due to the need to achieve switching and lifting of the dual nozzles, as well as the arrangement of the cutter, and considering the multiple requirements of not wanting wire overflow from the nozzle after operation, the switching cam is positioned close to the switching motor and at the top, while the pivot of the swing mechanism is positioned at the bottom, leaving the middle space for the extrusion wheel and cutter, thus achieving near-end extrusion and near-end cutting. The shorter the distance from the extrusion wheel to the hot end of the nozzle, the better. If the distance is longer, the control of the extrusion volume is more easily affected by wire deformation. The farther the cutter position is, the more material is wasted during material change. The distance between the cutter trigger point and the cutter shaft is greater than the distance between the cutter and the cutter shaft (force amplification effect), making cutting easier. At the same time, positioning the cutter shaft close to the pivot of the swing mechanism avoids the cutter occupying space in the lower hot-end air duct, which is beneficial for heat dissipation. Furthermore, the blade being encased inside the cutter is also safer.

[0152] The system also includes a guide cover 12, a follower slider 53, and a guide rail 54. The follower slider 53 has a sliding groove 531 on one side and slides in cooperation with the guide rail 54. The guide rail 54 is mounted on the guide cover 12, which is at least partially located below the extrusion wheel. The follower slider 53 has a sliding cavity 532 in a horizontal direction, and the first cutter 811 is slidably disposed in the sliding cavity 532. The first cutter mounting portion 8123 includes a receiving portion 8000 movably connected to the first pulling protrusion 8113. When the first pulling protrusion 8113 is in the first working position, it is located within the receiving portion 8000, and the first cutter 811 can be pulled by the first cutter rod 812. When the first pulling protrusion 8113 is at least in the second working position, it is located outside the receiving part 8000, and the first cutting rod 812 cannot pull the first cutting blade 811. The receiving part 8000 has an upper opening structure, and the first pulling protrusion 8113 enters or leaves the receiving part 8000 through the upper opening. The receiving part is a component that drives the first pulling protrusion to move. The receiving part 8000 can be a U-shaped opening groove, or it can be a structure with a wall thickness that decreases from bottom to top. The thicker lower wall can block the first pulling protrusion, so that the receiving part can drive the first pulling protrusion to move. The thinner upper wall can avoid the first pulling protrusion, so as to ensure that the first pulling protrusion can disengage from the receiving part.

[0153] The sliding groove 531 is a dovetail groove. It also includes a first guide member 55 and a second guide member 56, which are fixedly mounted on the guide cover 12 and used to guide the first wire and the second wire, respectively. The guide cover 12 also has a sliding positioning part 121, which guides the sliding of the second cutter 821. The follower slider 53 has a sliding channel 533, and the first guide member 55 slides in conjunction with the sliding channel 533 of the follower slider 53. It also includes a compression spring 57, which has a compression spring mounting part 534. One end of the compression spring 57 is fixed or abuts against the guide cover 12 or the mounting body, and the other end is located within the compression spring mounting part 534. The compression spring on the follower slider keeps it pressed against the movable hot end. This ensures the cutter can move up and down with the hot end and also keeps it pressed in place, preventing the drive slider from failing to fall smoothly due to unforeseen circumstances. This would prevent the preload magnetic element from suddenly attracting the drive block, reducing the impact noise when the drive slider contacts the positioning block at the bottom working position. Furthermore, by positioning the cutter's pivot above the cutter, the cutter moves up and down with the first nozzle, ensuring the cutting point is as close as possible to the hot end of the nozzle. Positioning the pivot above the cutter also ensures the cutter can move downwards relative to the cutter rod without being obstructed by the pivot.

[0154] gagging mechanism

[0155] As shown in Figures 23-29, the nozzle-closing mechanism includes a swing rod 901, a nozzle, a positioning magnetic element 905, a first guiding magnetic element 908, and a second guiding magnetic element 906. One end of the swing rod 901 is connected to the output shaft of the lifting motor 501, and the other end is rotatably connected to the nozzle. A positioning mounting part 9032 is provided on the nozzle, and the positioning magnetic element 905 is mounted on the positioning mounting part 9032. The nozzle switches between the first nozzle 51 and the second nozzle 52, and the orientation of the nozzle is maintained by the cooperation of the first guiding magnetic element 908, the second guiding magnetic element, and the positioning magnetic element 905. The nozzle only seals the first nozzle 51 or the second nozzle 52 when it is not in operation. Preferably, the nozzle-closing mechanism also includes an intermediate guiding magnetic element 907, which is arranged between the first guiding magnetic element 908 and the second guiding magnetic element 906. This intermediate guiding magnetic element 907 is used to change the orientation of the nozzle when the positioning magnetic element 905 passes through the intermediate guiding magnetic element 907 during the switching process between the first nozzle 51 and the second nozzle 52. Preferably, the nozzle plug includes a nozzle plug mounting base 903 and a nozzle plug baffle 904, with the nozzle plug baffle 904 fixedly installed to the nozzle plug mounting base 903. The nozzle plug baffle 904 is an elastic metal sheet, and elastic or flexible nozzle plug layers are provided at positions corresponding to the first and second nozzles on the nozzle plug baffle 904, with the elastic or flexible nozzle plug layers annularly sleeved on the nozzle plug baffle 904.

[0156] The nozzle baffle 904 has a first working position and a second working position, and the first nozzle 51 has an upward limit position and a downward limit position. The first working position of the nozzle baffle 904 corresponds to the upward limit position of the first nozzle 51, and the second working position of the nozzle baffle 904 corresponds to the second nozzle 52. A bending plate 909 is provided below the lifting motor 501. The bending plate 909 has a first horizontal part, a bending part, and a second horizontal part. A first guiding magnetic element 908 is provided on the first horizontal part, a middle guiding magnetic element 907 is inclinedly provided on the bending part, and a second guiding magnetic element 906 is provided on the second horizontal part. The distance between the first guiding magnetic element 908 and the middle guiding magnetic element 907 is greater than the distance between the middle guiding magnetic element 907 and the second guiding magnetic element 906. By setting the bending angle of the bending part, the orientation of the middle guiding magnetic element 907 can be adjusted, thereby adjusting the orientation of the nozzle during the nozzle switching process. When the nozzle-blocking baffle 904 is in the first working position, the positioning magnetic element 905 and the first guiding magnetic element 908 attract each other, and the nozzle-blocking baffle 904 is in a horizontal position, blocking the first nozzle 51. When the nozzle-blocking baffle 904 is in the second working position, the positioning magnetic element 905 and the second guiding magnetic element 906 attract each other, and the nozzle-blocking baffle 904 is in a horizontal position, blocking the second nozzle 52. When the positioning magnetic element 905 is in a position relative to the intermediate guiding magnetic element 907, the nozzle-blocking baffle 904 is tilted, so that when the nozzle-blocking baffle moves to the second working position, it moves at an angle tilted towards the second nozzle 52. The lifting motor 501 drives the first nozzle 51 and the nozzle-blocking mechanism 9 to move. When the first nozzle begins to descend from its upper limit position, the nozzle-blocking baffle moves before the first nozzle. When the first nozzle moves from its lower limit position towards its upper limit position, the first nozzle reaches the upper limit position first, and then the nozzle-blocking baffle reaches the first working position. The first and second guiding magnetic elements are horizontally positioned magnets, ensuring that the nozzle baffle horizontally blocks the first and second nozzles; the middle guiding magnetic element is an angled magnet, ensuring that the nozzle baffle cuts in at an angle, reducing the chance of the nozzle baffle getting stuck.

[0157] The swing arm 901 is a bent or arc-shaped rod, and it bends away from the drive slider 505. This arrangement ensures that the swing arm avoids the linear guide, and a gap is provided on the rear side of the fixed hot end to accommodate the movement of the swing arm.

[0158] The output shaft of the lifting motor is connected to the first drive shaft 5071 and the second drive shaft 5072 via the lifting motor reduction mechanism 507. The first drive shaft 5071 drives the first nozzle 51 to rise and fall. The second drive shaft 5072 is connected to one end of the swing rod 901. The shaft hole through which the drive rocker arm 502 engages with the first drive shaft 5071 can be a D-shaped hole or a flat hole. The first drive shaft can be a D-shaped shaft or a flat shaft. The sector gear has a D-shaped hole or a flat hole, and the second drive shaft is a D-shaped shaft or a flat shaft. The straight portion of the D-shaped shaft or flat shaft has a gap with the straight portion of the D-shaped hole or flat hole. This configuration of the D-shaped shaft ensures that the swing of the swing rod and the rise and fall of the first nozzle are decoupled within a certain range, thus making it less likely for the nozzle baffle to get stuck.

[0159] As mentioned above, the lifting electrode deceleration mechanism includes a lifting deceleration gearbox. A pair of Hall sensors can be installed on the outside of the gearbox. The pair of Hall sensors are arranged at 90° with the axis of the second transmission shaft 5072 as the center. At the same time, magnets are arranged on the sector gear. By cooperating with the Hall sensors, the rotation angle of the swing rod 901 can be detected.

[0160] Additionally, a pair of Hall sensors may be included for detecting the rotation angle of the drive rocker arm 502. The pair of Hall sensors are arranged at 90° around the axis of rotation of the drive rocker arm 502 and fixed relative to the mounting body, for example, also mounted outside the gearbox.

[0161] Cooling mechanism

[0162] As shown in Figures 2-7, a cooling mechanism is used to cool the upper portions of the first nozzle 51 and the second nozzle 52, and the area below the nozzle, respectively. The cooling mechanism includes a first cooling mechanism 6 and a second cooling mechanism 7, which are used to cool one of the upper portions of the first nozzle 51 and the second nozzle 52, and the area below the nozzle, respectively. The first cooling mechanism 6 includes a first fan 601; the second cooling mechanism 7 includes a second fan 701; wherein the first fan 601 and the second fan 701 are stacked and located on the side away from the output shaft of the extrusion motor. It also includes a fixed frame 13, which is connected to the mounting body. The first nozzle 51 includes at least one of a first heat dissipation assembly 511, a movable hot end 512, and a first nozzle 513, preferably including all three. The second nozzle 52 includes at least one of a second heat dissipation assembly 521, a fixed hot end 522, and a second nozzle 523, preferably including all three. The first cooling mechanism and the second cooling mechanism are disposed on the fixed frame 13. The first cooling mechanism also includes a first fan housing 602 and a first cooling channel 603. The second cooling mechanism 7 also includes a second fan housing 702 and a first fan housing 603. The second cooling channel 703 has a first fan 601 installed in the first fan housing 602, which has a first air outlet. The second fan housing 702 has a second fan 701 installed in the second fan housing 702, which has a second air outlet. The first air outlet is connected to the air inlet of the first cooling channel 603, and the air outlet of the first cooling channel 603 is aligned with the first heat dissipation component 511 and the second heat dissipation component 521. The second air outlet is connected to the air inlet of the second cooling channel 703, and the air outlet of the second cooling channel 703 is aligned with the first nozzle 513 and the second nozzle 523. Stacking the fans behind the linear guide rails provides space for the switching and extrusion mechanisms in front, and extends the airflow path, improving the overall cooling effect. The stacking of the fans reduces the size of the tool head. While cooling the heat dissipation components and nozzles, the fans also dissipate heat from the nearby motors and related circuit boards.

[0163] Both the first cooling channel 603 and the second cooling channel 703 are equipped with airflow guiding structures. These airflow guiding structures, such as deflectors, along the extended airflow path enable more uniform airflow.

[0164] Preferably, the first nozzle 51 or the lifting mechanism is also provided with a follow-up baffle 17, as shown in Figures 37-38. It is used to prevent the cooling air blown out of the first cooling channel 603 from blowing towards the heating area of ​​the first nozzle 51 at the upper limit position of the first nozzle 51, but to blow towards the first heat dissipation component 511, for example.

[0165] The follower baffle 17 preferably has a body portion 171, which is installed on the side of the heating area of ​​the first nozzle 51. When the first nozzle 51 is at its maximum rising position, the body portion 171 can block a portion of the opening of the first cooling channel 603 to prevent cooling air from blowing towards the heating area of ​​the first nozzle 51, thereby effectively reducing the probability of nozzle clogging. More preferably, the follower baffle 17 also has a bending portion 172, which is located at the upper edge of the body portion 171 and bends towards the first heat dissipation assembly 511. When the first nozzle 51 is at its maximum rising position, the cooling air is guided by the bending portion 172 and blown towards the first heat dissipation assembly 511.

[0166] Alternatively, the follower baffle 17 may not block the opening of the first cooling channel 603, but instead directly guides the cooling air to prevent it from blowing towards the heating area of ​​the first nozzle 51, while simultaneously directing the cooling air directly to the first heat dissipation assembly 511. In this embodiment, the follower baffle 17 is installed on the side of the heating area of ​​the first nozzle 51 and has a guide plate facing the first heat dissipation assembly 511. When the first nozzle 51 is at its maximum rising position, the opening of the first cooling channel 603 faces the guide plate, allowing the cooling air to be blown towards the first heat dissipation assembly 511 via the guide plate, thereby preventing the cooling air from blowing towards the heating area of ​​the first nozzle 51.

[0167] In this invention, when the first nozzle 51 is at its descent limit position, as shown in FIG40, the opening of the first cooling channel 603 on one side of the first nozzle 51 is aligned with the first heat dissipation assembly 511. Cooling air can be blown directly onto the first heat dissipation assembly 511 without being blocked and / or guided by the follower baffle 17, and will not blow onto the heating area of ​​the first nozzle 51. When the first nozzle 51 is at its ascending limit position, as shown in FIG41, the opening of the first cooling channel 603 on one side of the first nozzle 51 is no longer aligned with the first heat dissipation assembly 511, but is partially aligned with the heating area of ​​the first nozzle 51 and partially aligned with the first heat dissipation assembly 511. At this time, the blocking and / or guiding effect of the follower baffle 17 can prevent the cooling air from blowing onto the heating area of ​​the first nozzle 51, and even guide the cooling air to the first heat dissipation assembly 511, thereby effectively preventing the heating area of ​​the first nozzle 51 from being cooled and better promoting the heat dissipation of the first heat dissipation assembly 511, thus greatly reducing the probability of the nozzle being blocked.

[0168] As shown in Figures 40-41, in order to better utilize the function of the follow-up baffle, the opening of the first cooling channel 603 on one side of the first nozzle 51 can be designed to be larger than the opening of the first cooling channel 603 on the other side of the second nozzle 52 (Figure 40 shows the number of arrows, which indicates that the number of arrows at the opening of the first cooling channel 603 on the left side is greater than the number of arrows at the opening of the first cooling channel 603 on the right side, indicating that the opening on the left side is larger than the opening on the right side), thereby ensuring that the first nozzle 51 can provide sufficient heat dissipation for the first heat dissipation component 511 at both the rising limit position and the falling limit position.

[0169] The first fan housing cavity has a first air inlet, which corresponds to the extrusion motor; the second fan housing cavity has a second air inlet on both the inner and outer sides, with the inner second air inlet corresponding to the circuit board of the printing tool head, and the outer second air inlet connecting to the external environment.

[0170] Alternatively, another cooling mechanism layout (not shown) can be adopted. For example, the cooling mechanism includes a cooling fan, a first cooling channel 603', and a second cooling channel 703'. The air outlet of the first cooling channel 603' is aligned with the first heat dissipation component 511' and the second heat dissipation component 521', and the air outlet of the second cooling channel 703' is aligned with the first nozzle 513' and the second nozzle 523'. Each of the first and second cooling channels 603' and the air outlet of the cooling fan is equipped with a damper, allowing independent control of the airflow through the first and second cooling channels 603' and 703'. The airflow magnitude can also be adjusted by controlling the opening of the dampers. The air inlet of the cooling fan corresponds to the circuit board of the extrusion motor or printing head, providing cooling for the heat dissipation components and nozzles, as well as the nearby motor and related circuit boards.

[0171] Furthermore, a nozzle camera 14 and a worktable camera 15 can also be provided. The nozzle camera 14 is located below the lifting motor 501, in the middle area of ​​the first cooling channel 603 or the second cooling channel 703, and the worktable camera 15 is located outside the first cooling channel 603 or the second cooling channel 703. Supplementary lights are also included to cooperate with the nozzle camera 14 and the worktable camera 15 respectively.

[0172] The tool head housing can also be provided with a function expansion slot for installing function expansion accessories, such as laser heads, cutting blades, etc. The function expansion accessories are located at the front of the tool head housing, which ensures that the center of gravity of the tool head is further forward to balance the weight of the motor located at the rear.

[0173] The printing tool head of this application moves along a horizontally set linear guide, and the linear guide moves in a horizontal direction perpendicular to it. The first printhead and the second printhead are used to perform additive printing on the first filament and the second filament, respectively. The first printhead is a movable printhead that can be raised and lowered, and the second printhead is fixed. When the first printhead rises to its upper limit position, it is higher than the second printhead, and the second printhead starts to work. When the first printhead falls to its lower limit position, it is lower than the second printhead, and the first printhead starts to work. The process of switching the first nozzle 51 from the working state to the standby state is as follows: the switching motor 401 first drives the first pressure roller 413 to disengage from the extrusion roller 303, and then the lifting motor 501 drives the first nozzle 51 to rise, while controlling the extrusion mechanism to pull the wire to rise synchronously, keeping the wire relatively stationary inside the first nozzle; and / or, the process of switching the second nozzle 52 from the working state to the standby state is as follows: the switching motor 401 first drives the second pressure roller 423 to disengage from the extrusion roller 303, and then the lifting motor 501 drives the first nozzle 51 to descend; controlling the extrusion mechanism to pull the wire to descend synchronously, keeping the wire relatively stationary inside the first nozzle.

[0174] Meanwhile, the lifting mechanism and the nozzle-closing mechanism operate in a linked control manner, and both are driven by the lifting motor. The lifting motor 501 drives the first nozzle 51 and the nozzle-closing mechanism 9 to move. When the first nozzle begins to descend from its upper limit position, the nozzle-closing mechanism moves before the first nozzle. When the first nozzle moves from its lower limit position toward its upper limit position, the first nozzle reaches the upper limit position first, and then the nozzle-closing mechanism reaches its first working position. Specifically, the above-mentioned linkage can be achieved by setting the curved shape of the upper groove wall of the drive block 504's groove (such as a U-shaped groove 5043 or a closed groove).

[0175] For example, as shown in Figure 39, the curve of the upper wall of the U-shaped chute 5043 may include the following multiple curve segments: a first curve segment 5043a and a second curve segment 5043b. In this application, the first curve segment 5043a is the main curve segment that cooperates with the drive roller 503 when the drive block 504 rises and falls. In some embodiments, the first curve segment 5043a is a straight line segment or a rounded corner. The second curve segment 5043b is the curve segment that cooperates with the drive roller 503 before the drive block 504 begins to fall or after it finishes to rise. This curve segment is designed so that the drive block 504 remains in the original position without rising or falling as the drive roller 503 moves. In some embodiments, the second curve segment 5043b is an arc segment concentric with the rotation axis of the drive rocker arm 502. At least when the second curve segment 5043b cooperates with the drive roller 503, the plugging mechanism moves, but the drive block 504 does not rise or fall, thereby achieving the above-mentioned linkage.

[0176] Furthermore, the curve of the upper groove wall may also include a third curve segment 5043c, and a connecting curve segment located between the second curve segment 5043b and the third curve segment 5043c. The third curve segment 5043c is a self-locking curve segment or a limiting curve segment when the drive roller 503 rotates further after passing the highest or lowest point. It can be understood that after the drive roller 503 moves past the connecting curve segment, the drive roller 503 can continue to move at a certain angle, such as 5° or 10°, thereby enabling the drive rocker arm to achieve locking and positioning. Alternatively, after the drive roller 503 moves past the connecting curve segment, the drive roller 503 can continue to move at a certain angle to reach the third curve segment 5043c, thereby achieving self-locking or triggering mechanical limiting. For example, starting from the position shown in Figure 39 (when the drive block 504 and the first nozzle are at their upper limit positions), the drive roller 503 moves counterclockwise, first engaging with the second curved segment 5043b. At this time, the drive block 504 remains stationary, while the nozzle-closing mechanism moves, achieving decoupling of the lifting and lowering motion with the nozzle-closing mechanism's motion. Subsequently, the drive roller 503 continues to move counterclockwise, reaching the first curved segment 5043a. By this time, the nozzle-closing mechanism has moved a certain distance, and the drive block 504 begins to descend, with the first nozzle descending synchronously without interfering with the nozzle-closing mechanism. Afterward, as the drive roller 503 moves further counterclockwise, it will engage with the second curved segment 5043b again, while the drive block 504 continues to descend until the first nozzle reaches its lower limit position. Optionally, the drive roller 503 may continue to move thereafter, reaching a self-locking position or abutting the third curved segment 5043c to achieve self-locking or trigger a mechanical limit. When the drive block 504 and the first nozzle are at their lower limit position and begin to move upward, it is the reverse process described above. The drive roller 503 first contacts the first curved segment 5043a, driving the drive block 504 to rise. The first nozzle rises synchronously. When the drive roller 503 engages with the second curved segment 5043b, the first nozzle reaches its upper limit position. At this time, the drive block 504 remains stationary, while the nozzle blocking mechanism moves, achieving linkage decoupling between the lifting and lowering motion and the nozzle blocking mechanism motion. Optionally, the drive roller 503 may continue to move thereafter, reaching the self-locking position or abutting the third curved segment 5043c to achieve self-locking or triggering the mechanical limit.

[0177] The movable hot end is detachable and replaceable. Preferably, the follower baffle 17 and the cable fixing structure 16 are installed on the drive block 504, so that the movable hot end can be used on both the lifting side and the fixed side.

[0178] When the switching mechanism is running, when the switching cam 405 applies a biasing force to the second switching part 421, the second pressure roller 423 moves away from the extrusion roller 303, and the first pressure roller 413 moves closer to the extrusion roller 303, thus cooperating to convey the first wire; when the switching cam 405 applies a biasing force to the first switching part 411, the first pressure roller 413 moves away from the extrusion roller 303, and the second pressure roller 423 moves closer to the extrusion roller 303, thus cooperating to convey the second wire.

[0179] Regarding the prior art US2024 / 0009927A1 in the background art, in order to reduce its undesirable wire overflow, the ramp 291 of the mechanical switch 290 can be set as an arc surface, or the size of the base surface 293 connected to the ramp 291 can be larger than the ramp 291, so that the wire switching is faster relative to the rise and fall of the nozzle.

[0180] Regarding the prior art CN115091750B in the background art, in order to reduce its undesirable wire overflow, its inclined groove 242 can be improved from an inclined straight groove to an inclined arc groove, S-shaped groove or Z-shaped groove, so that the horizontal movement of the transmission block 420 is fast and the vertical movement is slow, that is, the wire switching is faster than the lifting and lowering of the nozzle.

[0181] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0182] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. An additive printing tool head, comprising a mounting body, a first printhead (51), a second printhead (52), and a filament channel; characterized in that: The mounting body is provided with an extrusion mechanism (3), a guide rail mounting part (101), a lifting mechanism (5), a first nozzle (51) and a second nozzle (52); the extrusion mechanism (3) includes an extrusion motor (301), and the lifting mechanism (5) includes a lifting motor (501); the extrusion motor (301) is installed on the first side of the mounting body and is located above the guide rail mounting part (101), and the lifting motor (501) is installed on the first side of the mounting body and is located below the guide rail mounting part (101).

2. The additive printing tool head as described in claim 1, characterized in that: It also includes a switching mechanism (4), which includes a switching motor (401) arranged side by side on one side of the extrusion motor (301).

3. The additive printing tool head as described in claim 2, characterized in that: The mounting body includes a first mounting part (1) and a second mounting part (2). The first mounting part (1) is at least partially fixed to the upper part of the second mounting part (2). The extrusion mechanism (3) and the switching mechanism (4) are disposed on the first mounting part (1). The lifting mechanism (5), the first nozzle (51) and the second nozzle (52) are disposed on the second mounting part (2). The guide rail mounting part (101) is disposed on the first mounting part (1) or the second mounting part (2).

4. The additive printing tool head as described in claim 2, characterized in that: It also includes a cooling mechanism for cooling the upper portions of the first nozzle (51) and the second nozzle (52) and the area below the nozzle, respectively.

5. The additive printing tool head as described in claim 4, characterized in that: The cooling mechanism includes a first cooling mechanism (6) and a second cooling mechanism (7), which are used to cool one of the upper part of the first nozzle (51) and the second nozzle (52) and the area below the nozzle, respectively. The first cooling mechanism (6) includes a first fan (601); the second cooling mechanism (7) includes a second fan (701); wherein the first fan (601) and the second fan (701) are stacked and located on the side away from the output shaft of the extrusion motor.

6. The additive printing tool head as described in claim 2, characterized in that: The tool head is mounted on the linear rail via the guide rail mounting part and can move in the X direction, while the linear rail can move in the Y direction; the switching mechanism (4) also includes a switching motor reduction mechanism (402), and the lifting mechanism (5) also includes a lifting motor reduction mechanism (507); the centroid of the tool head projected in the XY plane or the projection of the tool head's center of gravity in the XY plane coincides with the projection of the linear rail, and / or, at least one of the extrusion motor (301) and the switching motor (401) or the switching motor reduction mechanism (402), and at least one of the lifting motor (501) or the lifting motor reduction mechanism, have their projections in the XY plane at least partially overlap with the projection of the linear rail.

7. The additive printing tool head as described in claim 2, characterized in that: The switching mechanism (4) also includes a first transmission gear (403), a second transmission gear (404), a switching cam (405), a first swing mechanism (406), a second swing mechanism (407), and an elastic element (408); the switching motor reduction mechanism (402) is connected to the first transmission gear (403), and the first swing mechanism (406), the second swing mechanism (407), and the elastic element (408) are all located on the second side of the mounting body; the first transmission gear (403) and the second transmission gear (404) are meshed and connected, and the second transmission gear (404) drives the switching cam (405) to swing; the switching cam (405) is centrally located on the mounting body and above the first reduction gear (304); the first swing mechanism (406) and the second swing mechanism (407) are symmetrically arranged on both sides of the switching cam (405).

8. The additive printing tool head as described in claim 7, characterized in that: The first swing mechanism (406) includes a first switching part (411), a first hinge part (412), a first pressure roller (413), and a first swing pivot part (414) arranged sequentially from top to bottom; the second swing mechanism (407) includes a second switching part (421), a second hinge part (422), a second pressure roller (423), and a second swing pivot part (424) arranged sequentially from top to bottom; when the switching cam (405) applies a biasing force to the second switching part (421), the second switching part (421) moves away from the cam axis, and the first switching part (411) is in the elastic element (408). Under the action of the elastic element (408), the first pressure roller (423) moves away from the extrusion roller (303) and the second pressure roller (413) moves closer to the extrusion roller (303), thus cooperating to convey the first wire. When the switching cam (405) applies a biasing force to the first switching part (411), the first switching part (411) moves away from the cam axis, and the second switching part (421) moves towards the cam axis under the action of the elastic element (408). The first pressure roller (413) moves away from the extrusion roller (303) and the second pressure roller (423) moves closer to the extrusion roller (303), thus cooperating to convey the second wire.

9. The additive printing tool head as described in claim 8, characterized in that: The two ends of the elastic element (408) are respectively connected to the first hinge part (412) and the second hinge part (422); Alternatively, the elastic element (408) includes two elastic elements, the first ends of which are fixed ends, and the second ends are respectively connected to one of the first hinge portion (412) and the second hinge portion (422).

10. The additive printing tool head as described in claim 8, characterized in that: The elastic element (408) is a tension spring with its two ends connected to the first hinge (412) and the second hinge (422) respectively. When the switching cam (405) is in the middle state of the switching action, the spring tension is large. When the switching cam (405) drives the first switching part (411) or the second switching part (421) to the working position, the spring is in a non-horizontal state and the tension is small.

11. The additive printing tool head as described in claim 8, characterized in that: The first swing pivot (414) and the second swing pivot (424) are respectively disposed near the lower ends of the first swing mechanism (406) and the second swing mechanism (407).

12. The additive printing tool head as described in claim 1 or 7, characterized in that: The lifting mechanism (5) also includes a drive rocker (502), a drive roller (503), a drive block (504), a drive slider (505), and a drive slide rail (506); the drive rocker (502) and the drive roller (503) are located on the first side of the mounting body; one end of the drive rocker (502) is connected to the output shaft of the lifting motor (501) via transmission or direct connection, and the other end is provided with a drive roller (503); the drive slide rail (506) is located on the first side of the mounting body, and the drive slider (505) is slidably mounted on the drive slide rail. On the track (506); the drive block (504) is set on the first, second and third sides of the mounting body, the second side is the side opposite to the first side, the third side is the side connecting the first side and the second side, the drive block (504) is fixedly connected to the second side wall (5041) of the second side of the mounting body and the drive slider (505); a first nozzle (51) is provided on one side of the drive slider (505), and a groove that cooperates with the drive roller (503) is provided on the first side wall (5042) of the drive block (504) of the first side of the mounting body.

13. The additive printing tool head as described in claim 12, characterized in that: The slide is a U-shaped slide (5043), which has a closed side and an open side along the horizontal direction of the drive block (504). The drive roller (503) can be inserted into the U-shaped slide (5043) from the open side. When the lifting motor (501) drives the drive rocker (502) to rotate, the drive roller (503) moves toward the open side of the U-shaped slide (5043), so that the drive block (504) drives the drive slider (505) to move up and down along the drive slide rail (506).

14. The additive printing tool head as described in claim 12, characterized in that: The width of the U-shaped chute (5043) in the vertical direction is larger than that of the drive roller (503), so that the drive roller fits into the upper wall of the U-shaped chute (5043).

15. The additive printing tool head as described in claim 12, characterized in that: It also includes a plugging mechanism, which includes a swing rod (901), a plug, a positioning magnetic element (905), a first guiding magnetic element (908), and a second guiding magnetic element (906). One end of the swing rod (901) is connected to the output shaft of the lifting motor (501) for transmission, and the other end is rotatably connected to the plug. A positioning mounting part (9032) is provided on the plug, and a positioning magnetic element (905) is installed on the positioning mounting part (9032). The plug switches between the first nozzle (51) and the second nozzle (52), and the orientation of the plug is maintained by the cooperation of the first guiding magnetic element (908), the second guiding magnetic element (906), and the positioning magnetic element (905). The plug only seals the first nozzle (51) or the second nozzle (52) when it is not in operation.

16. The additive printing tool head as described in claim 15, characterized in that: The nozzle plugging mechanism also includes an intermediate guiding magnetic element (907), which is arranged between the first guiding magnetic element (908) and the second guiding magnetic element (906) to change the orientation of the nozzle when the positioning magnetic element (905) passes the intermediate guiding magnetic element (907) during the switching of the nozzle plugging between the first nozzle (51) and the second nozzle (52).

17. The additive printing tool head as described in claim 16, characterized in that: The lifting motor (501) drives the first nozzle (51) and the plugging mechanism (9) to move. When the first nozzle starts to descend from the upper limit position, the plugging baffle moves before the first nozzle. When the first nozzle moves from the lower limit position toward the upper limit position, the first nozzle reaches the upper limit position first, and the plugging baffle reaches the first working position.

18. The additive printing tool head as described in claim 5, characterized in that: It also includes a fixed frame (13) connected to the mounting body. The first nozzle (51) includes at least one of a first heat dissipation assembly (511), a movable hot end (512), and a first nozzle (513). The second nozzle (52) includes at least one of a second heat dissipation assembly (521), a fixed hot end (522), and a second nozzle (523). The first cooling mechanism and the second cooling mechanism are disposed on the fixed frame (13). The first cooling mechanism also includes a first fan housing cavity (602) and a first cooling channel (603). The second cooling mechanism (7) also includes a second fan housing cavity (702) and a second cooling channel (703). The first fan (601) is installed in the first fan housing cavity (602) and has a first air outlet. The second fan (701) is installed in the second fan housing cavity (702) and has a second air outlet. The first air outlet is connected to the air inlet of the first cooling channel (603) and the air outlet of the first cooling channel (603) is aligned with the first heat dissipation component (511) and the second heat dissipation component (521). The second air outlet is connected to the air inlet of the second cooling channel (703) and the air outlet of the second cooling channel (703) is aligned with the first nozzle (513) and the second nozzle (523).

19. The additive printing tool head as described in claim 18, characterized in that: The first nozzle (51) or the lifting mechanism is also provided with a follow-up baffle (17), which is used to prevent the cooling air blown out of the first cooling channel (603) from blowing towards the heating area of ​​the first nozzle (51) at the upper limit position of the first nozzle (51).

20. The additive printing tool head as described in claim 19, characterized in that: The follow-up baffle (17) is installed on the side of the heating area of ​​the first nozzle (51) and has a guide plate facing the first heat dissipation assembly (511). When the first nozzle (51) is at the upper limit position, the opening of the first cooling channel (603) faces the guide plate, so that the cooling air is blown towards the first heat dissipation assembly (511) through the guide plate, thereby preventing the cooling air from blowing towards the heating area of ​​the first nozzle (51).

21. An additive printer, characterized in that: It uses the additive printing tool head as described in any one of claims 1-20.

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