Multi-material wire supply system for space additive manufacturing and working method

Abstract

The invention provides a multi-material wire supply system for space additive manufacturing and a working method. The system comprises an elastic traction mechanism, a multi-wire pipe chain mechanism, an automatic opening and closing wire feeding mechanism, an upper base plate, a lower base plate and a nozzle. One end of a main body structure of the elastic traction mechanism is fixed on the upper substrate, and the other end is connected with the lower substrate to provide power for the multi-wire pipe chain mechanism to step, rotate and align to the nozzle; the multi-wire pipe chain mechanism is arranged outside the main body structure of the elastic traction mechanism and provides passive compact guiding and positioning for aligning the wire with the nozzle; the automatic opening and closing wire feeding mechanism is arranged at the other end of the elastic traction mechanism body structure and fixedly connected with the lower base plate, the multi-wire pipe chain mechanism drives different wires to be aligned with the nozzles when opened, the wires are automatically fed into the nozzles when closed, and the wires are melted or extruded after being melted. The space additive manufacturing multi-wire supply system can adapt to the extreme environment of space additive manufacturing and meet the constraint of limited space resources, and full automation and unmanned operation of space additive manufacturing multi-wire supply are achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of space additive manufacturing, and in particular to a multi-material wire feeding system and a working method for space additive manufacturing. Background Art

[0002] Space additive manufacturing refers to additive manufacturing carried out in a space environment. This integrated forming technology has brought new ideas to on-orbit in-situ manufacturing, and is expected to break through the limitations of rocket carrying volume, carrying mass, harsh mechanical conditions of the launch process and high transportation costs, and meet the actual needs of low-cost on-orbit construction of large-size and complex structural parts.

[0003] Multi-material additive manufacturing uses the performance advantages of different material combinations to solve the problem of insufficient mechanical properties of single-material manufacturing, providing a new way to improve the mechanical properties of space additive manufacturing parts. However, the existing multi-material additive manufacturing feeding system cannot meet the application requirements of space additive manufacturing. This is because space additive manufacturing is different from ground additive manufacturing. It not only needs to consider the serious impact of the extreme environment in space, but also faces the harsh restrictions of limited space resources, such as the limit constraints on the volume, weight, power and other aspects of the mechanism.

[0004] At present, there are two types of wire feeding methods in ground multi-material additive manufacturing: multi-wire material supply extruded by a single nozzle and multi-wire material supply extruded by multiple nozzles. In addition to the different number of nozzles, both require the use of multiple wire feeding extrusion mechanisms, which not only introduce multiple power sources, but also need to be supplemented by mechanical structures such as guides and transmissions. For example, if 10 materials are used, 10 sets of wire feeding extrusion mechanisms need to be configured, which brings additional volume, weight and power loss, and obviously cannot meet the actual needs of multi-material additive manufacturing under space resource constraints. Other researchers have proposed a solution for a single wire feeding mechanism to correspond to a multi-wire storage device, but it needs to rely on gravity-assisted feeding, and the alignment of the wire feeding mechanism and the wire storage device requires movement in three directions. In addition to using three motors to drive, several auxiliary structural parts are introduced. Its motion mechanism is complex, and there are problems such as bulky mechanism, large volume, high system power, and low reliability. In addition, space additive manufacturing faces unmanned application scenarios. The method of manually assisting in placing different wires into the wire feeding extrusion mechanism in ground additive manufacturing will no longer be applicable, and the method of relying on ground gravity to make the wire automatically fall into the guide mechanism will also fail directly. Under the dual constraints of extreme space environment and limited space resources, how to achieve automatic rotation of multi-filament raw materials in space additive manufacturing is an urgent problem to be solved. Summary of the invention

[0005] Based on this, it is necessary to provide a multi-material wire feeding system and working method for space additive manufacturing to address the above-mentioned technical problems.

[0006] A multi-material wire feeding system for space additive manufacturing, comprising: an elastic traction mechanism, a multi-wire tube chain mechanism, an automatic opening and closing wire feeding mechanism, an upper base plate, a lower base plate and a nozzle;

[0007] The elastic traction mechanism is a single power source with an elastic tensioning structure, one end of the main structure of the elastic traction mechanism is fixed to the upper base plate, and the other end of the main structure of the elastic traction mechanism is connected to one side of the lower base plate, and is used to provide power for the multi-wire tube chain mechanism to step and rotate to align with the nozzle;

[0008] The multi-wire tube chain mechanism is a linear array arrangement of multiple guide tubes and a double-end winding structure of a flexible base belt, which is arranged outside the main structure of the elastic traction mechanism and is used to provide passive compact guidance and positioning for the wire to align with the nozzle;

[0009] The automatic opening and closing wire feeding mechanism is arranged at the other end of the main structure of the elastic traction mechanism and is fixedly connected to the lower base plate, and is used for automatic opening and closing and automatic wire feeding. When the multi-wire tube chain mechanism is opened, the different wires are driven to align with the nozzles respectively, and when closed, the wires are automatically fed into the nozzles, so that the wires are melted or extruded after melting;

[0010] The nozzle is arranged on the other side of the lower substrate, and the filament is extruded through the nozzle.

[0011] In one embodiment, the elastic traction mechanism includes: an elastic tensioner, a traction main transmission, a traction slave transmission, a traction drive, a tube chain driving shaft, a tube chain driven shaft, a positioning shaft and a connecting shaft;

[0012] The elastic tensioner is installed on the upper side of the upper base plate and is used to provide tensioning force for positioning the multi-wire tube chain mechanism;

[0013] The traction main transmission is arranged on the upper side of the upper base plate and connected to the output shaft of the traction drive to provide the main traction force;

[0014] The traction slave transmission is arranged on the upper side of the upper base plate and is fixedly connected to the upper end of the tube chain driving shaft to provide slave traction force;

[0015] The traction drive is fixed to the lower side of the upper base plate, and the power of the traction drive is transmitted to the traction slave drive through the traction main drive, driving the tube chain driving shaft to rotate;

[0016] Bearings are installed at both ends of the tube chain driving shaft and the tube chain driven shaft, the upper end bearing is fixed inside the upper base plate, and the lower end bearing is fixed inside the lower base plate; the outer walls of the tube chain driving shaft and the tube chain driven shaft are respectively connected to the multi-wire tube chain mechanism;

[0017] The upper end of the positioning shaft is fixedly connected to the upper base plate, and is used to provide a positioning fulcrum for the multi-wire tube chain mechanism to align the nozzle;

[0018] The connecting shaft is disposed between the upper base plate and the lower base plate, and is used to fix the upper base plate and the lower base plate.

[0019] In one embodiment, the elastic tensioner includes: a coil spring holder, a coil spring and a top cover;

[0020] The coil spring holder is fixedly connected to the upper base plate, the coil spring is arranged in the coil spring holder, the central end is connected to the tube chain driven shaft, the outer end extends out and is fixed to the coil spring holder, the coil spring is connected and contracted with the tube chain driven shaft, and provides tensioning force for positioning the multi-wire tube chain mechanism;

[0021] During operation, the top cover is fixed to the coil spring holder to prevent the coil spring from popping out.

[0022] In one embodiment, a multi-wire tube chain mechanism includes: a plurality of guide tubes and a flexible base belt;

[0023] The plurality of guide tubes are equipped with the wires, arranged in a linear array and fixed in the flexible base belt; the guide tubes pass through the positioning shaft along with the flexible base belt, and the highest point is supported by the positioning shaft to help the wires in the guide tubes align with the nozzle;

[0024] One end of the flexible base belt is wound and fixed on the middle part of the driving shaft of the pipe chain, and the other end is wound and fixed on the middle part of the driven shaft of the pipe chain, so as to fix the guide pipe and provide rotational power.

[0025] In one embodiment, the automatic opening and closing wire feeding mechanism comprises: an active wire feeding unit, a follow-up wire feeding unit and an opening and closing unit;

[0026] The bottom of the active wire feeding unit is fixed on the lower base plate and is used to feed the wire into the nozzle;

[0027] The follower wire feeding unit is arranged between the active wire feeding unit and the opening and closing unit, is intermittently connected to the opening and closing unit, and has a bottom arranged on the lower base plate, and is used to cooperate with the active wire feeding unit to feed the wire into the nozzle;

[0028] The bottom of the opening and closing unit is fixed on the lower base plate and is used to control the distance between the follow-up wire feeding unit and the active wire feeding unit.

[0029] In one embodiment, the active wire feeding unit includes: a wire feeding drive, a wire feeding drive seat and a driving wheel;

[0030] The wire feeding drive is mounted on the wire feeding drive seat, the wire feeding drive seat is fixedly connected to the lower base plate, the driving wheel is fixedly connected to the output shaft of the wire feeding drive, and the driving wheel rotates continuously driven by the wire feeding drive.

[0031] In one embodiment, the follower wire feeding unit includes: a driven wheel, a driven wheel shaft, a spring base, an opening and closing slider, a slider guide seat, a spring shaft, an opening and closing trigger block and a spring;

[0032] The driven wheel is a rotating structure, with the driven wheel shaft installed in the center, and the driven wheel is fixed to the front end of the opening and closing slider along with the driven wheel shaft; the spring base is fixedly connected to the lower base plate, and the opening and closing slider is placed on the spring base, and the two sides are fixedly connected to the slider guide seat, and the spring is placed in the internal spring groove; the opening and closing slider can move forward and backward in a straight line, and the slider guide seat limits the opening and closing slider to limit the other degrees of freedom of movement of the opening and closing slider except the forward and backward straight line direction; the spring shaft is installed on the opening and closing slider and can be rotatably adjusted to the insertion depth to provide positioning and guidance for the spring; the opening and closing trigger block is fixedly connected to the end of the opening and closing slider, and the opening and closing trigger block is pushed and pulled to drive the opening and closing slider to move forward and backward in a straight line.

[0033] In one embodiment, the opening and closing unit includes: an opening and closing drive, an opening and closing drive seat and a drive finger;

[0034] The opening and closing drive is fixed on the opening and closing drive seat, the opening and closing drive seat is fixedly connected to the lower base plate, the driving finger is connected to the output shaft of the opening and closing drive, and the opening and closing drive can drive the driving finger to rotate to a fixed angle.

[0035] A working method of a multi-material wire feeding system for space additive manufacturing, applied to the multi-material wire feeding system for space additive manufacturing as described above, comprising:

[0036] The automatic opening and closing wire feeding mechanism is turned on, the elastic traction mechanism rotates, and the multi-wire tube chain mechanism rotates in coordination to align the designated wire with the nozzle;

[0037] The automatic opening and closing wire feeding mechanism is closed to press the wire in; the automatic opening and closing wire feeding mechanism automatically feeds the wire downward, and the wire is fed into the nozzle through the lower base plate; the automatic opening and closing wire feeding mechanism automatically rewinds the wire upward, and the wire is fed out of the nozzle through the lower base plate.

[0038] Compared with the prior art, the advantages and beneficial effects of the present invention are:

[0039] 1. The present invention discloses a multi-material wire feeding system for space additive manufacturing. Its multi-wire tube chain mechanism provides passive compact guidance and positioning for multiple wires to align with nozzles through a linear array arrangement of multiple guide tubes and a double-end winding design of a flexible base tape, thereby achieving integrated installation in a very small volume and solving the problem of miniaturization and lightweighting of the positioning and guiding of feeding of dozens of wires under space resource constraints.

[0040] 2. The elastic traction mechanism of the present invention is driven by a single power source and has an elastic tensioning structural design. In combination with a multi-wire tube chain mechanism, it can realize automatic alignment of dozens of wires with a single wire feeding mechanism by relying only on a single degree of freedom movement, thereby solving the problems of the existing mechanism with multiple degrees of freedom of movement, bulky mechanical structure, high energy consumption, and complex motion control, and meeting the requirements of unmanned, automated, miniaturized, low power consumption, and high reliability for multi-wire feeding under space resource constraints.

[0041] 3. The automatic opening and closing wire feeding mechanism of the present invention has both automatic opening and closing functions and automatic wire feeding functions. In conjunction with the elastic traction mechanism and the multi-wire tube chain mechanism, only a single set of wire feeding actuators is used. It can automatically select multiple wires in a space microgravity environment and automatically feed them into the nozzle. Under the constraints of limited resources, it can meet the use requirements in unmanned scenarios of space additive manufacturing.

[0042] 4. The present invention provides a multi-material wire supply working method for space additive manufacturing, which can adapt to the extreme environment of space additive manufacturing and meet the constraints of limited space resources, thereby realizing full automation and unmanned supply of multi-wire materials for space additive manufacturing.

[0043] 5. The multi-material wire feeding system of the present invention is applicable to a wide range of wire materials, including polymers and their composite materials, metals and their composite materials, polymer and metal composite materials, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 A schematic structural diagram of a multi-material wire feeding system for space additive manufacturing in one embodiment;

[0045] Figure 2 A schematic diagram of the structure of an elastic traction mechanism in a multi-material wire feeding system for space additive manufacturing in one embodiment;

[0046] Figure 3 It is a structural schematic diagram of an elastic tensioner in an elastic traction mechanism in an embodiment when the top cover is in an open state;

[0047] Figure 4 It is a schematic diagram of the unfolded structure of a multi-wire tube chain mechanism in a multi-material wire supply system for space additive manufacturing in one embodiment;

[0048] Figure 5It is a structural schematic diagram of an opening and closing wire feeding mechanism in a multi-material wire feeding system for space additive manufacturing in one embodiment;

[0049] Figure 6 A schematic cross-sectional view of an automatic opening and closing wire feeding mechanism in an open state in one embodiment;

[0050] Figure 7 It is a schematic cross-sectional structure diagram of an automatic opening and closing wire feeding mechanism in a closed state in one embodiment.

[0051] 1-elastic traction mechanism, 11-elastic tensioner, 111-coil spring holder, 112-coil spring, 113-top cover, 12-traction main drive, 13-traction slave drive, 14-traction drive, 15-tube chain driving shaft, 16-tube chain driven shaft, 17-positioning shaft, 18-connecting shaft, 2-multi-wire tube chain mechanism, 21-guide tube, 22-flexible base belt, 3-automatic opening and closing wire feeding mechanism, 31-active wire feeding unit, 311-wire feeding drive, 3 12-wire feeding drive seat, 313-driving wheel, 32-follow-up wire feeding unit, 321-driven wheel, 322-driven wheel shaft, 323-spring base, 324-opening and closing slider, 325-slider guide seat, 326-spring shaft, 327-opening and closing trigger block, 328-spring, 33-opening and closing unit, 331-opening and closing drive, 332-opening and closing drive seat, 333-driving finger, 4-upper substrate, 5-lower substrate, 6-nozzle, 7-wire. DETAILED DESCRIPTION

[0052] Before describing the specific embodiments of the present invention, the overall concept of the present invention is described as follows:

[0053] The present invention is mainly developed for space additive manufacturing. At present, there are two types of wire feeding methods in ground multi-material additive manufacturing: multi-wire material supply extruded by a single nozzle and multi-wire material supply extruded by multiple nozzles. In addition to the different number of nozzles, both require the use of multiple wire feeding extrusion mechanisms, which not only introduce multiple power sources, but also require mechanical structures such as guides and transmissions, which bring additional volume, weight and power loss, and cannot meet the actual needs of multi-material additive manufacturing under space resource constraints.

[0054] Therefore, the present invention proposes a multi-material wire supply system for space additive manufacturing, including: an elastic traction mechanism, a multi-wire tube chain mechanism, an automatic opening and closing wire feeding mechanism, an upper base plate, a lower base plate and a nozzle and other structures. It can adapt to the extreme environment of space additive manufacturing and meet the constraints of limited space resources, thereby realizing full automation and unmanned supply of multi-wire materials for space additive manufacturing.

[0055] After introducing the overall concept of the present invention, in order to make the purpose, technical solution and advantages of the present invention more clear, the embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements with the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0056] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined.

[0057] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or mutual communication; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0058] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0059] Figure 1 The schematic diagram of the structure of a multi-material wire feeding system for space additive manufacturing of the present invention is shown, which is mainly composed of an elastic traction mechanism 1, a multi-wire tube chain mechanism 2, an automatic opening and closing wire feeding mechanism 3, an upper base plate 4, a lower base plate 5 and a nozzle 6. One end of the main structure of the elastic traction mechanism 1 is fixed to the upper base plate 4, and the other end is connected to one side of the lower base plate 5. The multi-wire tube chain mechanism 2 is located between the upper base plate 4 and the lower base plate 5, and the two ends are respectively wound and fixed in the elastic traction mechanism 1; the automatic opening and closing wire feeding mechanism 3 is aligned with the nozzle 6 and fixed on the upper side of the lower base plate 5, and the nozzle 6 is located on the lower side of the lower base plate 5. A plurality of wires 7 are arranged in the multi-wire tube chain mechanism 2, and are melted or melted by the automatic opening and closing wire feeding mechanism 3 and then extruded through the nozzle 6.

[0060] The elastic traction mechanism 1 uses a single power source in conjunction with an elastic tensioning structure to provide power for the multi-wire tube chain mechanism 2 to step and rotate to align with the nozzle 6; the multi-wire tube chain mechanism 2 provides passive compact guidance and positioning for multiple wires 7 to align with the nozzle 6 respectively; the automatic opening and closing wire feeding mechanism 3 has both automatic opening and closing functions and automatic wire feeding functions. When opened, the multi-wire tube chain mechanism 2 drives different wires 7 to align with the nozzle 6 respectively. When closed, the wires 7 are automatically fed into the nozzle 6, so that the wires 7 are melted / melted and then extruded.

[0061] like Figure 2 and Figure 3 As shown, the elastic traction mechanism 1 is composed of an elastic tensioner 11, a traction main transmission 12, a traction slave transmission 13, a traction drive 14, a tube chain driving shaft 15, a tube chain driven shaft 16, a positioning shaft 17 and a connecting shaft 18; wherein, the elastic tensioner 11 is composed of a coil spring holder 111, a coil spring 112 and a top cover 113. The elastic tensioner 11 is installed on the upper side of the upper base plate 4, the coil spring holder 111 is fixed to the upper base plate 4, the coil spring 112 is located in the coil spring holder 111, the center end of which is connected to the tube chain driven shaft 16, and the outer end extends out and is fixed to the coil spring holder 111. When working, the top cover 113 is fixed to the coil spring holder 111 to prevent the coil spring 112 from popping out; the coil spring 112 is connected and contracted with the tube chain driven shaft 16 to provide tensioning force for positioning the multi-wire tube chain mechanism 2. The traction main transmission 12 is located on the upper side of the upper base plate 4 and is connected to the output shaft of the traction drive 14; the traction slave transmission 13 is located on the upper side of the upper base plate 4 and is fixed to the upper end of the tube chain driving shaft 15; the traction drive 14 is fixed on the lower side of the upper base plate 4, and its power is transmitted to the traction slave transmission 13 through the traction main transmission 12, driving the tube chain driving shaft 15 to rotate. Bearings are installed at both ends of the tube chain driving shaft 15 and the tube chain driven shaft 16, the upper end bearing is fixed inside the upper base plate 4, and the lower end bearing is fixed inside the lower base plate 5; the outer walls of the tube chain driving shaft 15 and the tube chain driven shaft 16 are respectively connected to the multi-wire tube chain mechanism 2. The upper end of the positioning shaft 17 is connected and fixed to the upper base plate 4 to provide a positioning fulcrum for the multi-wire tube chain mechanism 2 to align the nozzle 6. The connecting shaft 18 is used to fix the upper base plate 4 and the lower base plate 5.

[0062] like Figure 4 As shown, the multi-wire tube chain mechanism 2 is composed of a guide tube 21 and a flexible base belt 22. The batch guide tubes 21 are embedded with wires 7, which are arranged in a linear array and fixed in the flexible base belt 22. Figure 1 , Figure 2 and Figure 3 One end of the flexible base belt 22 is wound and fixed on the middle of the tube chain driving shaft 15, and the other end is wound and fixed on the middle of the tube chain driven shaft 16; the guide tube 21 passes through the positioning shaft 17 with the flexible base belt 22, and is supported by the positioning shaft 17 to the highest point, helping the wire 7 in the guide tube 21 to align with the nozzle 6.

[0063] like Figure 5 , Figure 6 and Figure 7 As shown, the automatic opening and closing wire feeding mechanism 3 is composed of an active wire feeding unit 31, a follower wire feeding unit 32 and an opening and closing unit 33. Among them, the active wire feeding unit 31 is composed of a wire feeding drive 311, a wire feeding drive seat 312 and a driving wheel 313. The wire feeding drive 311 is installed on the wire feeding drive seat 312, the wire feeding drive seat 312 is fixed to the lower base plate 5, and the driving wheel 313 is connected and fixed to the output shaft of the wire feeding drive 311. The driving wheel 313 can rotate continuously under the drive of the wire feeding drive 311.

[0064] The follower wire feeding unit 32 is composed of a driven wheel 321 , a driven wheel shaft 322 , a spring base 323 , an opening and closing slider 324 , a slider guide seat 325 , a spring shaft 326 , an opening and closing trigger block 327 and a spring 328 . The driven wheel 321 is rotatable, and a driven wheel shaft 322 is installed at the center thereof, and is fixed to the front end of the opening and closing slider 324 with the driven wheel shaft 322; the spring base 323 is fixed to the lower base plate 5, and the opening and closing slider 324 is placed thereon, and the two sides are fixed to the slider guide seats 325, and a spring 328 is placed in the internal spring groove; the opening and closing slider 324 can move forward and backward in a straight line, and the slider guide seat 325 limits the opening and closing slider 324, limiting the other degrees of freedom of movement of the opening and closing slider 324 except the forward and backward straight line direction; the spring shaft 326 is installed on the opening and closing slider 324, and can be rotated to adjust the insertion depth, providing positioning and guidance for the spring 328; the opening and closing trigger block 327 is fixed to the end of the opening and closing slider 324, and the opening and closing trigger block 327 is pushed and pulled to drive the opening and closing slider 324 to move forward and backward in a straight line.

[0065] The opening and closing unit 33 is composed of an opening and closing drive 331, an opening and closing drive seat 332 and a driving finger 333. The opening and closing drive 331 is fixed on the opening and closing drive seat 332, the opening and closing drive seat 332 is fixed to the lower base plate 5, and the driving finger 333 is connected to the output shaft of the opening and closing drive 331. The opening and closing drive 331 can drive the driving finger 333 to rotate to a certain angle.

[0066] When the automatic opening and closing wire feeding mechanism 3 is in the open state, the driving finger 333 rotates to a fixed angle under the drive of the opening and closing drive 331, pushes the opening and closing trigger block 327 and makes it retreat, the spring 328 is compressed, and under the constraint of the slider guide seat 325, the opening and closing trigger block 327 drives the opening and closing slider 324 to move backward in a straight line, and the driven wheel 321 then retreats and separates from the driving wheel 313, and the two are separated by a fixed gap.

[0067] When the automatic opening and closing wire feeding mechanism 3 is in a closed state, the driving finger 333 returns to the zero position along with the opening and closing drive 331, the opening and closing trigger block 327 moves forward, the spring 328 becomes longer, and the driven wheel 321 moves forward in a straight line along with the opening and closing slider 324 to contact the wire. After the spring 328 becomes longer, it is still in a compressed state. Under its action, the driven wheel 321 presses the wire into the guide groove of the driving wheel 313.

[0068] The implementation forms of the traction drive 14 and the wire feeding drive 311 include motor drive, hydraulic drive or pneumatic drive. The implementation forms of the traction main drive 12 and the traction slave drive 13 include synchronous belt drive, gear drive, belt drive, chain drive or friction drive. The spring 328 can be used alone or in groups at the same time. The connecting shaft 18 can be used alone or in groups at the same time. The wire material 7 applicable to the multi-material wire feeding system includes polymers and their composite materials, metals and their composite materials or metal and polymer composite materials. In this embodiment, when the wire material 7 is polylactic acid (PLA), the traction drive 14 and the wire feeding drive 311 are micro-stepping motors, the opening and closing drive is a micro-servo, the traction main drive 12 and the traction slave drive 13 are a pair of gears, two springs 328 are used, and a pair of connecting shafts 18 are installed.

[0069] In one embodiment, a working method of a multi-material wire feeding system for space additive manufacturing is provided, as follows:

[0070] Open the automatic opening and closing wire feeding mechanism 3: the driven wheel 321 moves backward and maintains a fixed distance with the driving wheel 313.

[0071] The elastic traction mechanism 1 rotates, and the multi-wire tube chain mechanism 2 cooperates to rotate to align the designated wire 7 with the nozzle 6: the traction drive 14 rotates, and the traction main transmission 12 and the traction slave transmission 13 transmit the transmission, and the tube chain driving shaft 15 rotates, driving the flexible base belt 22 fixed at one end of the tube chain driving shaft 15 to rotate, and the flexible base belt 22 fixed at one end of the tube chain driven shaft 16 rotates accordingly, the coil spring 112 is tensioned, and the designated wire 7 in the guide tube 21 moves with the flexible base belt 22 and is aligned with the nozzle 6 entrance.

[0072] Close the automatic opening and closing wire feeding mechanism 3: the driven wheel 321 moves backward, pressing the wire into the guide groove of the driving wheel 313.

[0073] The automatic opening and closing wire feeding mechanism 3 feeds the wire downward: the wire feeding drive 311 drives the driving wheel 313 to rotate clockwise, rolling the wire 7 to move downward, and the driven wheel 321 rotates frictionally accordingly, cooperating with the driving wheel 313 to feed the wire 7 into the nozzle 6;

[0074] The automatic opening and closing wire feeding mechanism 3 returns the wire upward: the wire feeding drive 311 drives the driving wheel 313 to rotate counterclockwise, rolling the wire 7 to move upward, and the driven wheel 321 rotates frictionally accordingly, cooperating with the driving wheel 313 to send the wire 7 out of the nozzle 6.

[0075] The advantages and beneficial effects of the present invention are:

[0076] 1. The present invention discloses a multi-material wire feeding system for space additive manufacturing. Its multi-wire tube chain mechanism provides passive compact guidance and positioning for multiple wires to align with nozzles through a linear array arrangement of multiple guide tubes and a double-end winding design of a flexible base tape, thereby achieving integrated installation in a very small volume and solving the problem of miniaturization and lightweighting of the positioning and guiding of feeding of dozens of wires under space resource constraints.

[0077] 2. The elastic traction mechanism of the present invention is driven by a single power source and has an elastic tensioning structural design. In combination with a multi-wire tube chain mechanism, it can realize automatic alignment of dozens of wires with a single wire feeding mechanism by relying only on a single degree of freedom movement, thereby solving the problems of the existing mechanism with multiple degrees of freedom of movement, bulky mechanical structure, high energy consumption, and complex motion control, and meeting the requirements of unmanned, automated, miniaturized, low power consumption, and high reliability for multi-wire feeding under space resource constraints.

[0078] 3. The automatic opening and closing wire feeding mechanism of the present invention has both automatic opening and closing functions and automatic wire feeding functions. In conjunction with the elastic traction mechanism and the multi-wire tube chain mechanism, only a single set of wire feeding actuators is used. It can automatically select multiple wires in a space microgravity environment and automatically feed them into the nozzle. Under the constraints of limited resources, it can meet the use requirements in unmanned scenarios of space additive manufacturing.

[0079] 4. The present invention provides a multi-material wire supply working method for space additive manufacturing, which can adapt to the extreme environment of space additive manufacturing and meet the constraints of limited space resources, thereby realizing full automation and unmanned supply of multi-wire materials for space additive manufacturing.

[0080] 5. The multi-material wire feeding system of the present invention is applicable to a wide range of wire materials, including polymers and their composite materials, metals and their composite materials, polymer and metal composite materials, etc.

[0081] Those skilled in the art should understand that the discussion of any of the above embodiments is merely illustrative and is not intended to imply that the scope of the present invention (including the claims) is limited to these examples. Under the concept of the present invention, the technical features in the above embodiments or different embodiments may be combined, the steps may be implemented in any order, and there are many other variations of the different aspects of the embodiments of the present invention as described above, which are not provided in detail for the sake of simplicity.

[0082] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, segment or portion of code that includes one or more executable instructions for implementing the steps of a specific logical function or process, and the scope of the preferred embodiments of the present invention includes alternative implementations in which functions may not be performed in the order shown or discussed, including performing functions in a substantially simultaneous manner or in the reverse order depending on the functions involved, which should be understood by those skilled in the art to which the embodiments of the present invention belong.

[0083] Where specific details have been set forth to describe exemplary embodiments of the present invention, it will be apparent to those skilled in the art that embodiments of the present invention may be implemented without these specific details or with variations thereto. Therefore, these descriptions should be considered illustrative rather than restrictive. Although the present invention has been described in conjunction with specific embodiments of the present invention, many replacements, modifications, and variations of these embodiments will be apparent to those of ordinary skill in the art based on the foregoing description.

[0084] The embodiments of the present invention are intended to cover all such substitutions, modifications and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the embodiments of the present invention should be included in the protection scope of the present invention.

Claims

1. A multi-material wire feeding system for space additive manufacturing, characterized in that: include: Elastic traction mechanism, multi-wire tube chain mechanism, automatic opening and closing wire feeding mechanism, upper base plate, lower base plate and nozzle; The elastic traction mechanism is a single power source with an elastic tensioning structure, one end of the main structure of the elastic traction mechanism is fixed to the upper base plate, and the other end of the main structure of the elastic traction mechanism is connected to one side of the lower base plate, and is used to provide power for the multi-wire tube chain mechanism to step and rotate to align with the nozzle; The multi-wire tube chain mechanism is a linear array arrangement of multiple guide tubes and a double-end winding structure of a flexible base belt, which is arranged outside the main structure of the elastic traction mechanism and is used to provide passive compact guidance and positioning for the wire to align with the nozzle; The automatic opening and closing wire feeding mechanism is arranged at the other end of the main structure of the elastic traction mechanism and is fixedly connected to the lower base plate, and is used for automatic opening and closing and automatic wire feeding. When the multi-wire tube chain mechanism is opened, the different wires are driven to align with the nozzles respectively, and when closed, the wires are automatically fed into the nozzles, so that the wires are melted or extruded after melting; The nozzle is arranged on the other side of the lower substrate, and the filament is extruded through the nozzle.

2. A multi-material wire feeding system for space additive manufacturing according to claim 1, characterized in that: The elastic traction mechanism comprises: an elastic tensioner, a traction main transmission, a traction slave transmission, a traction drive, a tube chain driving shaft, a tube chain driven shaft, a positioning shaft and a connecting shaft; The elastic tensioner is installed on the upper side of the upper base plate and is used to provide tensioning force for positioning the multi-wire tube chain mechanism; The traction main transmission is arranged on the upper side of the upper base plate and connected to the output shaft of the traction drive to provide the main traction force; The traction slave transmission is arranged on the upper side of the upper base plate and is fixedly connected to the upper end of the tube chain driving shaft to provide slave traction force; The traction drive is fixed to the lower side of the upper base plate, and the power of the traction drive is transmitted to the traction slave drive through the traction main drive, driving the tube chain driving shaft to rotate; Bearings are installed at both ends of the tube chain driving shaft and the tube chain driven shaft, the upper end bearing is fixed inside the upper base plate, and the lower end bearing is fixed inside the lower base plate; the outer walls of the tube chain driving shaft and the tube chain driven shaft are respectively connected to the multi-wire tube chain mechanism; The upper end of the positioning shaft is fixedly connected to the upper base plate, and is used to provide a positioning fulcrum for the multi-wire tube chain mechanism to align the nozzle; The connecting shaft is disposed between the upper base plate and the lower base plate, and is used to fix the upper base plate and the lower base plate.

3. A multi-material wire feeding system for space additive manufacturing according to claim 2, characterized in that: The elastic tensioner comprises: a coil spring holder, a coil spring and a top cover; The coil spring holder is fixedly connected to the upper base plate, the coil spring is arranged in the coil spring holder, the central end is connected to the tube chain driven shaft, the outer end extends out and is fixed to the coil spring holder, the coil spring is connected and contracted with the tube chain driven shaft, and provides tensioning force for positioning the multi-wire tube chain mechanism; During operation, the top cover is fixed to the coil spring holder to prevent the coil spring from popping out.

4. A multi-material wire feeding system for space additive manufacturing according to claim 2, characterized in that: The multi-wire tube chain mechanism comprises: a plurality of guide tubes and a flexible base belt; The plurality of guide tubes are equipped with the wires, arranged in a linear array and fixed in the flexible base belt; the guide tubes pass through the positioning shaft along with the flexible base belt, and the highest point is supported by the positioning shaft to help the wires in the guide tubes align with the nozzle; One end of the flexible base belt is wound and fixed on the middle of the driving shaft of the pipe chain, and the other end is wound and fixed on the middle of the driven shaft of the pipe chain, so as to fix the guide pipe and provide rotational power.

5. The multi-material wire feeding system for space additive manufacturing according to claim 1, characterized in that: The automatic opening and closing wire feeding mechanism comprises: an active wire feeding unit, a follow-up wire feeding unit and an opening and closing unit; The bottom of the active wire feeding unit is fixed on the lower base plate and is used to feed the wire into the nozzle; The follower wire feeding unit is arranged between the active wire feeding unit and the opening and closing unit, is intermittently connected to the opening and closing unit, and has a bottom arranged on the lower base plate, and is used to cooperate with the active wire feeding unit to feed the wire into the nozzle; The bottom of the opening and closing unit is fixed on the lower base plate and is used to control the distance between the follower wire feeding unit and the active wire feeding unit.

6. A multi-material wire feeding system for space additive manufacturing according to claim 5, characterized in that: The active wire feeding unit comprises: a wire feeding drive, a wire feeding drive seat and a driving wheel; The wire feeding drive is mounted on the wire feeding drive seat, the wire feeding drive seat is fixedly connected to the lower base plate, the driving wheel is fixedly connected to the output shaft of the wire feeding drive, and the driving wheel rotates continuously driven by the wire feeding drive.

7. A multi-material wire feeding system for space additive manufacturing according to claim 5, characterized in that: The follower wire feeding unit comprises: a driven wheel, a driven wheel shaft, a spring base, an opening and closing slider, a slider guide seat, a spring shaft, an opening and closing trigger block and a spring; The driven wheel is a rotating structure, with the driven wheel shaft installed in the center, and the driven wheel is fixed to the front end of the opening and closing slider along with the driven wheel shaft; the spring base is fixedly connected to the lower base plate, and the opening and closing slider is placed on the spring base, and the two sides are fixedly connected to the slider guide seat, and the spring is placed in the internal spring groove; the opening and closing slider can move forward and backward in a straight line, and the slider guide seat limits the opening and closing slider to limit the other degrees of freedom of movement of the opening and closing slider except the forward and backward straight line direction; the spring shaft is installed on the opening and closing slider and can be rotatably adjusted to the insertion depth to provide positioning and guidance for the spring; the opening and closing trigger block is fixedly connected to the end of the opening and closing slider, and the opening and closing trigger block is pushed and pulled to drive the opening and closing slider to move forward and backward in a straight line.

8. The multi-material wire feeding system for space additive manufacturing according to claim 5, characterized in that: The opening and closing unit comprises: an opening and closing drive, an opening and closing drive seat and a drive finger; The opening and closing drive is fixed on the opening and closing drive seat, the opening and closing drive seat is fixedly connected to the lower base plate, the driving finger is connected to the output shaft of the opening and closing drive, and the opening and closing drive can drive the driving finger to rotate to a fixed angle.

9. A working method of a multi-material wire feeding system for space additive manufacturing, characterized in that: A multi-material wire feeding system for space additive manufacturing as described in any one of claims 1 to 8, comprising: The automatic opening and closing wire feeding mechanism is turned on, the elastic traction mechanism rotates, and the multi-wire tube chain mechanism rotates in coordination to align the designated wire with the nozzle; The automatic opening and closing wire feeding mechanism is closed to press the wire in; the automatic opening and closing wire feeding mechanism automatically feeds the wire downward, and the wire is fed into the nozzle through the lower base plate; the automatic opening and closing wire feeding mechanism automatically rewinds the wire upward, and the wire is fed out of the nozzle through the lower base plate.

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