A dual-shaft retractable feeding stirring friction processing device and a method of use

Abstract

The application provides a feeding stirring friction processing device based on double-shaft retractable, which comprises a shell, a compression ring with a feeding hole, a shearing sleeve and a stirring needle are installed at the bottom end of the shell, the stirring needle and the shearing sleeve are axially, rotationally and complexly movable, a material guiding mechanism or a material cutting mechanism is arranged between the compression ring and the shearing sleeve, and the bottom surface of the shearing sleeve and the stirring needle is provided with a groove-shaped stirring structure; the application provides a multi-position processing method using the processing device, a flexible filler high-performance repairing method and a method for solving the shaft movement and vibration in the solid phase stirring process. The application avoids the phenomenon of tool blockage, realizes multi-position additive manufacturing, realizes accurate control of the filler and efficient repair of complex defects, and solves the problems of joint thinning, inability to immediately fill the filler after stopping the furnace and inability to once-form flexible filler repair in the prior art.

Description

Technical Field

[0001] This invention relates to the field of materials processing technology, and in particular to a biaxial retractable feeding stirring friction processing device and its usage method. Background Technology

[0002] Additive manufacturing, an advanced technology that creates complex structures by adding materials layer by layer, has been widely used in aerospace, medical and automotive manufacturing fields due to its advantages such as high material utilization, short manufacturing cycle and strong geometric adaptability.

[0003] Traditional additive manufacturing technologies are mostly based on molten or liquid materials (such as laser cladding and electron beam melting), but these processes suffer from high heat input, coarse microstructure, and element loss, limiting their application in special materials (such as aluminum-lithium alloys) and special environments (such as underwater). In recent years, solid-state additive manufacturing technology has become a research hotspot due to its characteristic of achieving material bonding through solid-state plastic deformation without the need for material melting.

[0004] During launch and atmospheric reentry, satellites are prone to structural defects such as cracks and holes on their surfaces due to high temperatures and high speeds, severely affecting their structural strength and service life. Traditional fusion welding repair techniques (such as arc welding and laser welding) rely on the melting and solidification process of materials, which has significant drawbacks: excessive heat input leads to lithium element burn-off and grain coarsening in aluminum-lithium alloys, resulting in decreased mechanical properties; stable arc initiation is impossible in underwater repair scenarios; and fusion welding causes large thermal deformations, especially for thin-walled structures, which can easily cause irreversible dimensional deviations.

[0005] Friction welding, as a solid-state joining technology, achieves material bonding through frictional heat generation and mechanical extrusion, avoiding the thermal damage problems of fusion welding and enabling stable welding in underwater environments. Backfill-type friction spot welding, in particular, uses a clamping ring to constrain material flow, combined with the axial movement of the stirring pin and sleeve, to achieve keyhole-free welding, making it suitable for crack repair. However, this process has inherent drawbacks: to avoid void defects, the stirring tool needs to be driven downwards by approximately 0.2 mm, leading to thinning of the thin-walled structure and a significant decrease in strength; the solid-state joining mechanism limits the effective introduction of filler material, making it difficult to optimize the composition for specific defect characteristics.

[0006] In traditional friction stir welding (FSW), a shoulder and stirring pin are inserted into the parts to be joined. Under the constraint of extrusion pressure, heat is generated through friction, shearing, and extrusion, ultimately achieving a solid-state bond. The advantage of FSW is that it does not require filler during the joining process. However, to achieve sufficient heat input, the shoulder usually needs to be pressed into the substrate, which leads to thinning of the plate and reduces the effective bonding area of ​​the joint. Furthermore, FSW is difficult to implement in solid-state additive manufacturing. Therefore, how to use filler has become a current technical bottleneck.

[0007] In current additive manufacturing methods, the additive feeder friction stir welding technology described in Chinese patent (CN115647564A) achieves simultaneous wire feeding and additive manufacturing through a wire feeding kit. However, friction and shearing cause the material to soften sufficiently, leading to easy blockage of the feed port. To avoid heat accumulation causing the filler material to fully plasticize and adhere to the feed port, a cooling device is conventionally used. Furthermore, brief "furnace shutdowns" during additive manufacturing cause the material to harden and block subsequent feeding. Chinese patent (CN116988134B) uses electrochemical cleaning technology to solve the problem of aluminum shavings adhering to the tool head, but it still suffers from issues such as chemical reaction residues affecting joint performance, the inability to immediately add material after furnace shutdown, and limitations on the types of materials that can be fed. Currently, Chinese patent (202310600837.9) uses differential feeding to decouple the spindle speed from the feeding speed, avoiding the problem of excessive material plasticization. However, the wire moves upwards during continuous feeding through the sleeve, thus requiring the development of corresponding equipment.

[0008] Whether welding or additive manufacturing, the presence of the stirring pin leads to keyhole problems at the end stage and easily causes volume defects during the manufacturing and service of reusable satellite structures. Chinese patent (CN114406443B) employs a combination of active and passive friction stir repair, using a customized welding column placed in a pre-fabricated repair hole, utilizing the heat generated by the rotating shoulder to repair the defect. However, this method suffers from joint overheating due to shoulder stirring and poor material flowability at the root. Chinese patent (CN110773860A) proposes friction plug welding technology, requiring the design of plug parameters based on the keyhole size, repairing the defect through rotational friction between the plug and the defect. However, this requires pre- and post-treatment and is not suitable for thin-walled structures. Chinese patent (CN115740726A) describes a floating friction stir welding device that achieves continuous additive welding, but keyhole defects still exist in the stirring head at the end of the additive process, and the interfacial bonding strength between the filler and the substrate is insufficient. In summary, current repair technologies struggle to achieve high-quality repair with one-time forming and flexible filler.

[0009] Furthermore, when employing robotic welding / additive manufacturing processes, especially with harder or thicker metals, the robot's flexible nature, particularly in complex poses, alters its own stress characteristics, affecting its applied force. During welding / additive manufacturing, the force applied by the robot increases with the degree of pose deformation, leading to a tendency for the spindle to "jump" during operation. This makes it difficult for the joint material to reach a steady state, significantly reducing joint quality. Currently, the mainstream approach is to use larger, heavier-duty robots. However, this significantly increases costs, and the robot's own weight has a greater impact on its stiffness in complex poses. Therefore, a new solution is urgently needed. Summary of the Invention

[0010] The purpose of this invention is to provide a biaxial retractable feeding stirring friction processing device and its usage method, so as to achieve precise control of the filler, interface strengthening and efficient repair of complex defects.

[0011] This invention provides a biaxial retractable feeding and stirring friction processing device, comprising a cylindrical shell, a hollow through-hole clamping ring with a feeding hole installed at the bottom end of the shell, a hollow through-hole shearing sleeve for axial movement, rotational movement, and a combination of both inside the clamping ring, a stirring needle for axial movement, rotational movement, and a combination of both inside the shearing sleeve, a cutting and feeding channel formed between the clamping ring and the shearing sleeve, a guiding mechanism or a cutting mechanism provided in the cutting and feeding channel, and grooved stirring structures respectively provided on the bottom surfaces of the shearing sleeve and the stirring needle.

[0012] Furthermore, the housing is composed of multiple hollow connecting columns, which are stacked along the axial direction and connected by fixing studs. A top end cap is provided at the top of the housing, and a six-dimensional force sensor is installed on the top end cap. A stationary outer shell is provided at the bottom of the housing, and a clamping ring is installed at the port of the stationary outer shell. A feeder is installed on the stationary outer shell, and multiple vibrators are installed on the stationary outer shell.

[0013] Furthermore, the housing is equipped with a first ball spline screw and a second ball spline screw that drive the stirring needle and the shearing sleeve respectively. The first ball spline screw consists of a first lead screw and a first ball nut and a first ball spline mounted on the first lead screw, and the first ball nut and the first ball spline are rotatably connected to the housing. The second ball spline screw consists of a hollow second lead screw and a second ball nut and a second ball spline mounted on the second lead screw, and the second ball nut and the second ball spline are rotatably connected to the housing. The first ball nut, the first ball spline, the second ball nut, and the second ball spline are each connected to a motor through a gear transmission mechanism, and the motor is mounted on the housing.

[0014] Furthermore, the bottom end of the second lead screw is connected to the shearing sleeve through a sleeve connector, and the bottom end of the first lead screw extends through the second lead screw into the sleeve connector and is connected to the stirring needle through a connecting cap.

[0015] Furthermore, the material guiding mechanism includes a spiral groove formed on the inner wall of the clamping ring and a feeding thread provided on the outer wall of the shearing sleeve. The spiral groove is located above the feeding thread and is connected to the feeding hole and the feeding thread. A coiled spring roller is provided on the spiral groove near the feeding hole. The bottom end face of the shearing sleeve is provided with an annularly distributed arc-shaped needle-shaped groove, and the bottom end face of the stirring needle is provided with a lateral groove.

[0016] Furthermore, the cutting mechanism includes a feeding thread disposed on the outer wall of the shearing sleeve and a guillotine portion disposed on the bottom edge of the shearing sleeve, and the clamping ring is clearance-fitted with the cutting structure; the bottom end face of the shearing sleeve is provided with a toothed groove, and the bottom end face of the stirring needle is provided with an evenly distributed arc-shaped long groove.

[0017] This invention provides a multi-position welding and additive manufacturing method based on a dual-axis retractable feeding stirring friction processing device. The differential rotation of the motor causes the first ball spline screw and the second ball spline screw to drive the stirring needle and the shearing sleeve to perform axial movement, rotational movement, and a combination of both. The material is fed into the spiral groove through the feeding hole and pre-formed into a spring shape. The rotating spring-shaped wire is then screwed into the shearing sleeve and continuously fed to the arc-shaped needle groove on the bottom end face of the shearing sleeve. Through the extrusion and shearing of the arc-shaped needle groove on the bottom end face of the shearing sleeve, and the high-speed rotation of the stirring needle stirring and friction, multi-position continuous additive manufacturing or non-thinning welding is achieved.

[0018] This invention provides a flexible, high-performance repair method for fillers based on a biaxially retractable feeding and stirring friction processing device, comprising the following steps:

[0019] S1, Pre-welding preparations;

[0020] S2, Use a defect scanner to determine the location of defects and distinguish the types of defects;

[0021] S3: Obtain the defect location, determine the feeding volume, and sequentially perform the cutting stage, material control stage, bottoming stage, dwell stage, pullback stage, and withdrawal stage to end the repair.

[0022] S4. Determine whether the repair is complete based on non-destructive testing. If not, perform multi-point welding to repair again until no defects are detected, then the repair is complete.

[0023] Furthermore, S3 includes:

[0024] Cutting stage: One or more materials are fed into the feeding hole, while the guillotine part reciprocates up and down in the feeding hole to flexibly feed the material. The volume of the fed material is greater than the volume of the defect.

[0025] Material control stage: Press the rotating guillotine blade and the bottom end of the stirring needle flush into the material at the defect;

[0026] The insertion stage: Select the insertion method according to the size of the defect. When the defect size is large, use the sleeve insertion method, insert the shear sleeve and pull back the stirring needle at the same time. When the defect size is small, use the needle insertion method, insert the stirring needle and pull back the shear sleeve at the same time.

[0027] Dwelling phase: The shear sleeve and stirring needle maintain their rotational axis and remain stationary;

[0028] Retraction phase: The shear sleeve and stirring needle retract synchronously;

[0029] Withdrawal phase: The shear sleeve and stirring needle reduce their rotation speed and move upwards slowly, until the main shaft is finally withdrawn.

[0030] The present invention also provides a vibration control method for a biaxial retractable feeding stirring friction processing device, comprising the following steps:

[0031] a. Install and connect a six-dimensional force sensor to detect the axial force F of the spindle in real time. Z Forward resistance F XY ;

[0032] b. Install exciters 0-4, and use them in conjunction with exciters 1-4 to excite vibration in any direction on the horizontal plane of the main shaft. Exciter 0 excites vibration in the direction perpendicular to the horizontal plane of the main shaft.

[0033] c. In actual solid-state stirring processes, an auxiliary vibrator is used to obtain the optimal vibrator power P1 and the optimal stress range F of the structural region through the microstructure and mechanical properties. XY1 -F XY2 and F Z1 -F Z2 This enables solid-phase mixing of high-quality structures;

[0034] d. For harder materials where smooth control is difficult, the force F during solid-state stirring can be monitored in real time. XY and F Z The magnitude and direction of the resultant force are determined. When the force exceeds the optimal force range, the power of the optimal exciter is increased, and when the force is below the optimal force range, the power of the optimal exciter is decreased. The goal is to achieve compliant control of the solid-phase stirring process.

[0035] This invention enhances the longitudinal mixing of materials through the relative movement of the shearing sleeve and the stirring needle, decoupling the wire feeding speed from the spindle speed. The spiral groove pre-forms the material into a spring shape, facilitating continuous material feeding and enabling multi-position additive manufacturing. The material is directly extruded through the feeding sleeve, forming a plasticized and compressed state only in the root needle area, avoiding blockage between the clamping ring and the shearing sleeve and solving the problem of material sticking to the blade. The addition of a cutting stage using a guillotine enhances the longitudinal flow and compression of the material, ensuring thorough mixing between the added material and the base material. This reinforces the repair joint with the strengthening particles, achieving high-performance and high-efficiency defect repair. It solves problems such as structural thinning, filling difficulties, and unstable repair quality in existing technologies, enabling flexible filling repair with one-time forming immediately after furnace shutdown. The combination of a six-dimensional force sensor and a vibrator solves the problem of the spindle's "jerking" vibration during solid-phase stirring, improving repair accuracy. Attached Figure Description

[0036] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0037] Figure 1 This is a schematic diagram of the biaxial retractable feeding, stirring, and friction processing device of the present invention.

[0038] Figure 2 For the present invention Figure 1 Enlarged view of point A in the middle;

[0039] Figure 3 This is a schematic diagram of the sleeve connector of the present invention;

[0040] Figure 4 This is a schematic diagram of the synchronous coil spring feeding mechanism of the present invention;

[0041] Figure 5 This is a cross-sectional view of the clamping ring in this invention;

[0042] Figure 6 For the present invention Figure 5 Middle BB section view;

[0043] Figure 7 This is a schematic diagram of the shearing sleeve in this invention;

[0044] Figure 8 This is a schematic diagram of the bottom structure of the synchronous coil spring feeding mechanism of the present invention;

[0045] Figure 9 This is a schematic diagram of the asynchronous wire feeding mechanism in Embodiment 2 of the present invention;

[0046] Figure 10 This is a cross-sectional view of the clamping ring in Embodiment 2 of the present invention;

[0047] Figure 11 This is a cross-sectional view of the shearing sleeve in Embodiment 2 of the present invention;

[0048] Figure 12 This is a schematic diagram of the bottom structure of the asynchronous wire feeding mechanism in Embodiment 2 of the present invention;

[0049] Figure 13 This is a flowchart of the method in Embodiment 2 of the present invention;

[0050] Figure 14 This is a displacement coordinate diagram of the tool used in the ligation-type repair scheme of Embodiment 2 of the present invention;

[0051] Figure 15 This is a displacement coordinate diagram of the tool used in the needle-piercing repair scheme of Embodiment 2 of the present invention;

[0052] Figure 16 This is a schematic diagram of the vibration suppression process of the present invention;

[0053] Explanation of reference numerals in the attached figures:

[0054] In the diagram: 1-Stationary outer shell; 2-Pressure ring; 201-Synchronous coil spring feeding mechanism, 2011-Feeding hole, 2012-Coil spring roller, 2013-Spiral groove, 2014-Fixing countersunk hole; 203-Asynchronous wire cutting feeding mechanism, 2031-Fixing hole, 2032-Feeding hole, 2033-Spinning part; 3-Sleeve connector; 301-Connecting sleeve, 302-ER chuck, 303-ER chuck cap, 304-Sleeve cap; 4-Connecting cap; 5-Shearing sleeve; 501-Connecting part, 502-Disassembly part, 503-Transition part, 504-Feeding thread, 505-Hollow part, 508-Guillotine part, 509-Constant thread; 6-Stirring needle; 701-Additive stirring mechanism, 7011-Arc-shaped needle groove, 7012 - Lateral groove; 7013-Dry extension; 702-Repair stirring mechanism; 7014-Toothed groove; 7015-Arc-shaped long groove; 8-Top end cap; 9-First ball nut; 10-First nut motor; 11-First transmission belt; 12-First transmission gear; 13-First connecting post; 14-First ball spline; 15-First spline motor; 16-Second connecting post; 17-First lead screw; 18-Second ball nut; 19-Second nut motor; 20-Fourth connecting post; 21-Second ball spline; 22-Second spline motor; 23-Second lead screw; 24-Second transmission belt; 25-Second transmission gear; 26-Fixing stud; 27-Feeder; 28-Six-dimensional force sensor; 29-Vibrator; 30-Third connecting post; 31-Material; Detailed Implementation

[0055] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0056] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0057] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the stated features. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified. Furthermore, the terms "installed," "connected," and "linked" should be interpreted broadly; for example, they may refer to a fixed connection, a detachable connection, or an integral connection; they may refer to a mechanical connection or an electrical connection; they may refer to a direct connection or an indirect connection through an intermediate medium; and they may refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0058] Example 1

[0059] like Figures 1-8 As shown:

[0060] A biaxial retractable feeding stirring friction processing device includes a cylindrical shell, which is composed of a hollow first connecting column 13, a second connecting column 16, a third connecting column 30 and a fourth connecting column 20. The four connecting columns are stacked along the axial direction, and the four connecting columns have connecting screw holes that are through and coaxially arranged along the height direction. Fixing screws 26 are inserted into the connecting screw holes.

[0061] A top end cover 8 is provided at the top of the housing, and a six-dimensional force sensor 28 is installed on the top of the top end cover 8. The top end cover 8 can be connected only to the top of the first connecting post 13, or it can be connected to the housing through fixing bolts passing through the four connecting posts. In use, the top end cover 8 can be connected to a robot or CNC machine tool through the six-dimensional force sensor 28.

[0062] like Figure 1 and Figure 2 As shown, a stationary outer shell 1 is detachably mounted on the bottom surface of the fourth connecting post 20 at the bottom of the housing. The bottom surface of the fourth connecting post 20 is provided with a mounting hole, and the stationary outer shell 1 and the mounting hole can be connected by bolts.

[0063] The bottom of the stationary housing 1 has a port through which the stirring friction component passes. A hollow through-hole clamping ring 2 is installed at the bottom of the stationary housing 1. A vibrator 29 and a feeder 27 are also installed on the stationary housing 1.

[0064] The through space of the feeding structure is coaxially arranged with the port of the stationary shell 1, and the through space of the feeding structure is also used for the stirring friction component to pass through.

[0065] The outer wall of the clamping ring 2 is provided with a feeding hole 2011 for feeding material 31 to enter. The feeding hole 2011 is a circular or rectangular hole and is connected to the feeder 27.

[0066] Material 31 is divided into wire, strip, and powder. Its material can be: metallic materials such as iron, aluminum, magnesium, copper, and titanium, as well as non-metallic matrix materials such as thermoplastic resins, thermosetting resins, ceramics, and graphite. Material 31 can also be one or more types. The reinforcing alloy powder is a metallic material such as scandium, zirconium, niobium, and titanium powder, or a non-metallic material such as carbon nanotubes, graphene nanosheets, and ceramic particles. The reinforcing base powder accounts for less than 8% of the total feed volume, and the powder diameter is at or below the micrometer level.

[0067] If the material 31 is filamentous or strip-shaped, it is directly inserted into the feeding hole 2011; if the material 31 is powdery or blocky, it is conveyed to the feeding hole 2011 through the conveying pipe. In this embodiment, the material 31 is a filament with a diameter of D, and the diameter of the feeding hole 2011 is > D + 0.05 mm.

[0068] The clamping ring 2 is provided with a hollow through shearing sleeve 5, and a stirring needle 6 is provided inside the shearing sleeve 5. A cutting and feeding channel is formed between the clamping ring 2 and the shearing sleeve 5, and a material guiding mechanism is provided inside the cutting and feeding channel.

[0069] like Figure 1As shown, the stirring needle 6 is connected to a first ball spline 14 screw that drives the stirring needle 6 to perform axial movement, rotational movement and a combination of both, and the shearing sleeve 5 is connected to a second ball spline 21 screw that drives the shearing sleeve 5 to perform axial movement, rotational movement and a combination of both.

[0070] The first ball spline screw 14 and the second ball spline screw 21 are housed inside the housing. The first ball spline screw 14 and the second ball spline screw 21 are configured by intersecting ball screw grooves and ball spline grooves on a single shaft, or by machining the ball screw and ball spline separately on the same shaft. This allows the component to achieve both rotational and linear motion conversion, as well as torque transmission. The ball spline screw is an existing device, and its specific structure will not be described in detail.

[0071] The first ball spline 14 lead screw consists of a first lead screw 17, a first ball nut 9 mounted on the first lead screw 17, and a first ball spline 14. The first ball nut 9 is rotatably mounted in the first connecting post 13, and the first ball spline 14 is rotatably mounted in the second connecting post 16.

[0072] The first ball nut 9 and the first ball spline 14 are respectively connected to the first nut motor 10 and the first spline motor 15 via gear transmission mechanisms. The gear transmission mechanism includes a first transmission gear 12, which is mounted on the output shafts of the first nut motor 10 and the first spline motor 15, as well as on the first ball nut 9 and the first ball spline 14. The first transmission gear 12 of the first nut motor 10 and the first transmission gear 12 of the first ball nut 9 are connected and driven by a first transmission belt 11; the first transmission gear 12 of the first spline motor 15 and the first transmission gear 12 of the first ball spline 14 are also connected and driven by the first transmission belt 11.

[0073] The second ball spline 21 lead screw consists of a hollow, through-hole second lead screw 23 and a second ball nut 18 and a second ball spline 21 mounted on the second lead screw 23. The second ball nut 18 is rotatably mounted in the third connecting post 30, and the second ball spline 21 is rotatably mounted in the fourth connecting post 20.

[0074] The second ball nut 18 and the second ball spline 21 are respectively connected to the second nut motor 19 and the second spline motor 22 via gear transmission mechanisms. The gear transmission mechanism includes a second transmission gear 25, which is mounted on the output shafts of the second nut motor 19 and the second spline motor 22, as well as on the second ball nut 18 and the second ball spline 21. The second transmission gear 25 of the second nut motor 19 and the second transmission gear 25 of the second ball nut 18 are connected and driven by a second transmission belt 24; the second transmission gear 25 of the second spline motor 22 and the second transmission gear 25 of the second ball spline 21 are also connected and driven by the second transmission belt 24.

[0075] The outer wall of the first connecting column 13 is provided with a fixing bracket for mounting the first nut motor 10 and the first spline motor 15 respectively; the outer wall of the third connecting column 30 is provided with a fixing bracket for mounting the second nut motor 19 and the second spline motor 22 respectively.

[0076] like Figures 1-3 As shown, the bottom end of the second lead screw 23 is connected to the shearing sleeve 5 through the sleeve connector 3, and the bottom end of the first lead screw 17 extends through the second lead screw 23 into the sleeve connector 3 and is connected to the stirring needle 6 through the connecting cap 4.

[0077] The sleeve connector 3 consists of a connecting sleeve 301, an ER collet 302, an ER nut 303, and a sleeve cap 304. The connecting sleeve 301 is threadedly fastened to the ER nut 303. The ER collet 302 is clamped between the connecting sleeve 301 and the ER nut 303. The sleeve cap 304 is installed inside the ER nut 303. The connecting sleeve 301 is threadedly fastened to the bottom end of the second lead screw 23. The sleeve cap 304 is threadedly fastened to the top end of the shearing sleeve 5.

[0078] The tightening directions of the shear sleeve 5, connecting sleeve 301, and ER clamp 303 are consistent and opposite to the rotation direction of the second lead screw 23 during operation.

[0079] The connecting cap 4 is threadedly fastened to the bottom end of the first lead screw 17, and the stirring needle 6 is engaged between the first lead screw 17 and the connecting cap 4.

[0080] The clamping ring 2, shearing sleeve 5, stirring needle 6, first lead screw 17 and second lead screw 23 are coaxially arranged.

[0081] By adjusting the rotational speeds of the first ball nut 9 and the first ball spline 14 to match the speeds of the first nut motor 10 and the first spline motor 15, the stirring needle 6 can achieve axial movement, rotational movement, and a combination of both. By adjusting the speed difference between the second nut motor 19 and the second spline motor 22 to the second ball nut 18 and the second ball spline 21, the shearing sleeve 5 can achieve axial movement, rotational movement, and a combination of both. This results in differential rotation and retraction of the stirring needle 6 and the shearing sleeve 5.

[0082] Taking the first ball spline 14 lead screw as an example, when the first ball nut 9 and the first ball spline 14 rotate at the same speed, the middle first lead screw 17 only rotates; when the first ball nut 9 rotates while the first ball spline 14 does not rotate, the middle first lead screw 17 moves axially; when the first ball nut 9 and the first ball spline 14 rotate at different speeds, if the difference between the first ball nut 9 and the first ball spline 14 is clockwise, they rotate in combination and move downwards along the axial direction; similarly, if the difference is counterclockwise, they rotate in combination and move upwards along the axial direction.

[0083] The materials of the shearing sleeve 5, the stirring needle 6 and the pressing ring 2 are made of materials with hardness and wear resistance better than or at least the same as those of heat-treated H13 and HM1 steels.

[0084] As Figure 1 , Figures 4-8 shown, in this embodiment, the pressing ring 2, the shearing sleeve 5 and the stirring needle 6 form a synchronous scroll spring feeding mechanism 201 for the multi-position continuous additive manufacturing process of the processing device.

[0085] In this embodiment, the feeding mechanism includes a spiral groove 2013 formed on the inner wall of the pressing ring 2 and a feeding thread 504 provided on the outer wall of the shearing sleeve 5. The spiral groove 2013 is located above the feeding thread 504, and the spiral groove 2013 and the feeding thread 504 are in communication and cooperation. The pitch of the spiral groove 2013 is D L , its minor diameter is D0, its major diameter is D1. The initial end of the spiral groove 2013 is connected and internally tangent to the feeding hole 2011, and the feeding angle of the feeding hole is less than arctan((D L / 2) / D0)°. A scroll spring roller 2012 is provided at a position of the spiral groove 2013 close to the feeding hole 2011, and the outer diameter of the scroll spring roller 2012 is externally tangent to the major diameter of the spiral groove 2013.

[0086] A fixed counterbore 2014 for connecting the stationary housing 1 is formed at the top of the pressing ring 2.

[0087] The shearing sleeve 5 is composed of a connecting part 501, a disassembling part 502, a transition part 503 and a feeding thread 504. The connecting part 501 is arranged at the top of the sleeve body for connecting with the cap 304 of the sleeve connecting piece 3; the disassembling part 502 is located below the connecting part 501, a shoulder is provided between the disassembling part 502 and the connecting part 501, and parallel planes are cut on both sides of the cylinder of the disassembling part 502; the shaft body of the sleeve body is the transition part 503; the feeding thread 504 is arranged at the bottom of the outer wall of the sleeve body, and the rotation direction of the feeding thread 504 is opposite to the rotation direction of the spiral groove 2013 through the material 31, and the shearing direction when the feeding thread 504 rotates is the same as the direction of piercing into the additive component; a through hollow part 505 is formed in the sleeve body.

[0088] The outer diameter of the transition part 503 is D2, D2 < D0, the pitch of the feeding thread 504 is D L , the bottom width of the thread of the feeding thread 504 is greater than the bottom width of the thread of the spiral groove 2013, the inner diameter of the feeding thread 504 is D2, the outer diameter of the feeding thread 504 is D3, D3 < D1, and (D3 - D2) / 2 > D. The outer diameter of the dry elongation 7013 of the stirring needle 6 is D6, and the inner diameter of the hollow part 505 is D4 > D6.

[0089] The bottom end face of the shear sleeve 5 is provided with annularly distributed arc-shaped needle-like grooves 7011. The radial edge of the arc-shaped needle-like grooves 7011 is inclined in the direction of rotation and the angle between the radial edge and the root extension is greater than 30°. The bottom end face of the stirring needle 6 is provided with toothed lateral grooves 7012. The extended part is the dry extension length 7013, the length of which is greater than the thickness of the additive layer + the distance from the bottom of the inclined needle-like grooves 7011 to the bottom end face of the synchronous coil spring feeding mechanism 201. The arc-shaped needle-like grooves 7011 and the lateral grooves 7012 constitute the additive stirring mechanism 701.

[0090] During additive manufacturing, the material 31 enters the synchronous coil spring feeding mechanism 201 through the feeding hole 2011 and is formed into a spring shape. The material 31 enters the spiral groove 2013 and is screwed into the groove of the feeding thread 504. Then, it is screwed into the shearing sleeve 5 and transported to the additive mixing mechanism 701 for rotation, extrusion and friction to achieve multi-position continuous additive manufacturing.

[0091] This embodiment provides a multi-position welding and additive manufacturing method based on a dual-axis retractable feeding stirring friction processing device. The first nut motor 10 and the first spline motor 15, and the second nut motor 19 and the second spline motor 22 drive differential rotation, which causes the first ball spline 14 lead screw and the second ball spline 21 lead screw to drive the stirring needle 6 and the shearing sleeve 5 to perform axial movement, rotational movement, and a combination of both, respectively. The first lead screw 17 and the second lead screw 23 achieve differential rotation. The material 31 is fed into the synchronous coil spring feeding mechanism 201 prefabricated into a spring shape. Subsequently, the rotating spring-shaped wire is screwed into the shearing sleeve 5 and continuously fed to the arc-shaped needle groove 7011 on the bottom end face of the shearing sleeve 5. Through the extrusion and shearing of the arc-shaped needle groove 7011 on the bottom end face of the shearing sleeve 5, the stirring needle 6 rotates at high speed to stir and rub. The lateral groove 7012 of the stirring needle 6 enhances radial stirring, forming a cavity metal in the space of the dry extension 7013, realizing multi-position continuous additive manufacturing or non-thinning welding.

[0092] To avoid thinning of the sheet metal and reduction of the effective joint area during friction stir welding, the feed rate is greater when using non-thinning welding than when using additive manufacturing.

[0093] Example 2

[0094] Figures 9-16 As shown, in this embodiment, the clamping ring 2, the shearing sleeve 5, and the stirring needle 6 form an asynchronous wire feeding mechanism 203, used for the high-performance repair process of the flexible filler in the processing device. The difference between this embodiment and Embodiment 1 is that a cutting mechanism is provided in the feeding channel, replacing the guiding mechanism.

[0095] In this embodiment, the cutting mechanism includes a feeding thread 504 disposed on the outer wall of the shearing sleeve 5 and a guillotine portion 508 disposed on the bottom edge of the shearing sleeve 5. In this embodiment, the feeding thread 504 is a constant thread 509.

[0096] The top of the clamping ring 2 is provided with a fixing hole 2031 for connecting the stationary housing 1. In this embodiment, the feeding hole 2032 of the clamping ring 2 is provided with multiple radially and obliquely opened holes. The bottom end of the clamping ring 2 is a spun part 2033.

[0097] The shearing sleeve 5 consists of a connecting part 501, a disassembly part 502, a constant thread 509, and a guillotine part 508. The connecting part 501 is located at the top of the sleeve body and is used to connect with the cap 304 of the sleeve connector 3. The disassembly part 502 is located below the connecting part 501, and a shoulder is provided between the disassembly part 502 and the connecting part 501. The cylindrical sides of the disassembly part 502 are cut with parallel planes. The shaft of the sleeve body is the transition part 503. The constant thread 509 is located at the bottom of the sleeve body. When the constant thread 509 rotates, the axial component of the shearing force is consistent with the insertion direction. The guillotine part 508 is the right angle where the bottom end face and the side face of the sleeve body meet, and no chamfering is required. The sleeve body has a through hollow part 505.

[0098] Another difference between this embodiment and embodiment 1 is that the thread and pitch of the feeding thread 504 on the shearing sleeve 5 are larger in embodiment 1, while the thread and pitch of the constant thread 509 on the shearing sleeve 5 are smaller in this embodiment.

[0099] The 508 guillotine cutter can be flexibly made of the following alloys or composite materials: tool steel, cemented carbide, high-temperature alloys, ceramic tools, diamond-coated tools, and titanium-plated end mills. The coating can be: titanium nitride coating, titanium carbide coating, alumina coating, tungsten carbide, or multilayer coatings (titanium nitride and titanium carbide coatings, alumina and titanium nitride coatings), or vapor-deposited solid materials such as metals, ceramics, or the cutting edge can be directly selected from cemented carbide or metal powder sintered with diamond particles.

[0100] The bottom end face of the shear sleeve 5 is provided with a radially opened toothed groove 7014, the depth of which is 0.1-3mm; the bottom end face of the stirring needle 6 is provided with an annularly distributed arc-shaped long groove 7015, and the toothed groove 7014 and the arc-shaped long groove 7015 constitute the repair stirring mechanism 702.

[0101] The feed hole 2032 is located within the axial movement cutting range of the shearing sleeve 5, ensuring that the guillotine section 508 can cut the material 31 passing through the feed hole 2032 within its axial range, and that the vertical distance from the bottom end face is greater than 3mm. The inner diameter D5 of the spinning section 2033 is D3+0.05≤D5≤D3+1mm, and the pitch of the constant thread 509 is D...LS <3*D, the constant thread 509 is distributed from the bottom of the shear sleeve 5 upwards. The total thread length of the constant thread 509 does not exceed 20*D. LS .

[0102] During repair, material 31 is fed into asynchronous guillotine feeding mechanism 203 through feeding hole 2032. Shearing sleeve 5 moves axially under the drive of the second ball spline 21 screw. Guillotine part 508 of shearing sleeve 5 cuts material 31 into strips or pieces and pushes them to the defect. Through the thorough mixing and stirring of repair stirring mechanism 702, shearing sleeve 5 and stirring needle 6 use a purging or needle purging repair scheme to squeeze and stir the fed material 31 with the substrate to achieve repair.

[0103] like Figure 9 and Figure 13 As shown, this embodiment provides a flexible, high-performance repair method for fillers based on a biaxially retractable feeding and stirring friction processing device, including the following steps:

[0104] S1, Pre-welding preparation work: remove oil stains, remove residual metal from tools and match the corresponding tooling fixtures;

[0105] S2, using a defect scanner to determine the location of defects and distinguish the types of defects, including missing defects, cracks or pores;

[0106] S3, obtain the defect location, determine the feeding volume through the defect scanner, and sequentially perform the cutting stage, material control stage, jacking stage, dwell stage, pullback stage and withdrawal stage to end the repair;

[0107] Cutting stage: One or more materials are fed into the feeding hole 2032, while the guillotine part 508 reciprocates up and down in the feeding hole 2032 to flexibly feed the material. The volume of the fed material is greater than the volume of the defect.

[0108] Material control stage: Press the bottom surfaces of the rotating guillotine part 508 and the stirring needle 6 flush into the material at the defect;

[0109] The insertion stage: Select the insertion method according to the different defect sizes. When the defect size is larger than the outer diameter of the stirring needle 6, the sleeve insertion method is used, the shearing sleeve 5 is inserted and the stirring needle 6 is withdrawn at the same time; when the defect size is smaller than the outer diameter of the stirring needle 6, the needle insertion method is used, the stirring needle 6 is inserted and the shearing sleeve 5 is withdrawn at the same time.

[0110] During the dwell phase: the shear sleeve 5 and the stirring needle 6 maintain their rotational axis and remain stationary;

[0111] Pullback stage: The shear sleeve 5 and the stirring needle 6 pull back simultaneously;

[0112] Withdrawal phase: The shear sleeve 5 and stirring needle 6 reduce their rotation speed and slowly move upward by 1mm, and the main shaft withdraws;

[0113] S4. Determine whether the repair is complete based on non-destructive testing. If not, perform multi-point welding to repair again until no defects are detected, then the repair is complete.

[0114] like Figure 14 and Figure 15 As shown, with the bottom end face of the asynchronous wire feeding mechanism 203 as the origin, and the bottom end faces of the shearing sleeve 5 and the stirring needle 6 as the reference objects, downward thrust is the negative direction and upward thrust is the positive direction. Assume that the volume of the defect is V and the maximum depth of the defect is H mm.

[0115] Cutting stage: Material 31 is fed into the feeding hole 2032, while the guillotine part 508 reciprocates up and down in the feeding hole 2032 to flexibly feed the material. The volume of the material 31 fed in is V1, and V1>V. Material control stage: The rotating guillotine part 508 and the stirring needle 6 press their bottom surfaces flush into part of the material 31. During the insertion phase, the insertion method is selected according to different defect sizes, including ligation and needle insertion. In ligation: the shear sleeve 5 is inserted to -Hmm, while the stirring needle 6 retracts. The space below the stirring needle 6 within the shear sleeve 5 is the retraction chamber, and the volume of material compressed by the insertion of the shear sleeve 5 is equal to the volume within the retraction chamber of the stirring needle 6. In needle insertion: the stirring needle 6 is inserted to the absolute position -Hmm, while the shear sleeve 5 retracts axially. The space between the clamping ring 2 and the stirring needle 6 below the shear sleeve 5 is the retraction chamber, and the volume of material compressed by the insertion of the stirring needle 6 is equal to the volume within the retraction chamber of the shear sleeve 5. During the dwell phase, the shear sleeve 5 and the stirring needle 6 maintain their rotational axis and remain stationary. During the retraction phase, for both needle insertion and ligation: the shear sleeve 5 and the stirring needle 6 move simultaneously to (V1-V) / (π*(D) LS / 2) 2 -0.1mm. Withdrawal stage: The shear sleeve 5 and stirring needle 6 reduce their speed and slowly move upward by 1mm, then the main shaft withdraws.

[0116] When the defect is a missing defect, first, the location of the defect is obtained, and the required feeding volume V1 is determined. Then, the cutting stage, material control stage, bottoming stage, dwell stage, and pullback stage are performed sequentially. During the pullback stage, both the stirring needle 6 and the shearing sleeve 5 are pulled back (V1-V) / (π*(D)). LS / 2) 2 -0.1mm, and finally the stirring needle 6 and shear sleeve 5 go through the withdrawal stage, ending the repair.

[0117] When the defect is a crack or porosity, first determine the location of the crack or porosity, and then determine the feeding volume V2. The following stages are performed sequentially: cutting, controlling, lowering, holding, and retraction. During the retraction stage, both the stirring pin 6 and the shearing sleeve 5 retract V2 / (π*(D)). LS / 2) 2 -0.1mm, and finally the stirring needle 6 and shear sleeve 5 go through the withdrawal stage, ending the repair.

[0118] The repaired structures include: wall panel structures, rib structures, and corner rib structures.

[0119] like Figure 16 As shown, this is a vibration suppression control method. The control of each dimension is as follows. This method can be applied to the problem of "jerking" vibration of the spindle during solid-state stirring processes such as friction stir welding or solid-state additive manufacturing in robots or machine tools. The specific implementation method is as follows: a. Install and connect the six-dimensional force sensor 28 to detect the axial force F of the electric spindle in real time. Z Forward resistance F XY b. Install exciter 290-4, and in conjunction with exciters 291-294, excite vibration in any direction on the horizontal plane of the main shaft. Exciter 290 excites vibration in the direction perpendicular to the horizontal plane of the main shaft. c. In the actual solid-state stirring process, assist exciter 29, and obtain the optimal exciter power P1 of exciter 29 through microstructure and mechanical properties, and obtain the stress range F of the optimal structural region. XY1 -F XY2 and F Z1 -F Z2 This achieves high-quality solid-state stirring; d. For harder materials where smooth control is difficult, the force F during the solid-state stirring process can be monitored in real time. XY and F Z The magnitude and direction of the resultant force are determined. When the force exceeds the optimal force range, the power of the optimal exciter 29 is increased, and when the force is below the optimal force range, the power of the optimal exciter 29 is decreased. The rate of increasing or decreasing the power can be achieved by any control method, such as robust control or PID control, with the goal of achieving compliant control of the solid-phase stirring process.

[0120] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A dual-shaft retractable feeding, stirring, and friction processing device, characterized in that, The device includes a cylindrical shell, with a hollow, through-hole clamping ring installed at the bottom end of the shell. The clamping ring contains a hollow, through-hole shearing sleeve that can move axially, rotate, or in combination with both. The shearing sleeve contains a stirring needle that can move axially, rotate, or in combination with both. A cutting and feeding channel is formed between the clamping ring and the shearing sleeve. A guiding mechanism is provided in the cutting and feeding channel. The bottom surfaces of the shearing sleeve and the stirring needle are respectively provided with grooved stirring structures. The material guiding mechanism includes a spiral groove formed on the inner wall of the clamping ring and a feeding thread formed on the outer wall of the shearing sleeve. The spiral groove is located above the feeding thread and is connected to the feeding hole and the feeding thread. A coiled spring roller is provided near the feeding hole in the spiral groove. The bottom end face of the shearing sleeve has an evenly distributed arc-shaped needle-like groove. The bottom end face of the stirring needle has a lateral groove. The differential rotation of the motor causes the first ball spline screw and the second ball spline screw to drive the stirring needle and the shearing sleeve to perform axial movement, rotational movement, and a combination of both, respectively. The material is fed into the spiral groove through the feeding hole and pre-formed into a spring shape. The rotating spring-shaped wire is then screwed into the shearing sleeve and continuously fed to the arc-shaped needle-like groove on the bottom end face of the shearing sleeve.

2. The biaxially retractable feeding, stirring, and friction processing device according to claim 1, characterized in that, The housing is composed of multiple hollow connecting columns, which are stacked along the axial direction and connected by fixing studs. A top end cap is provided at the top of the housing, and a six-dimensional force sensor is installed on the top end cap. A stationary shell is provided at the bottom of the housing, and a clamping ring is installed at the port of the stationary shell. A feeder is installed on the stationary shell, and multiple vibrators are installed on the stationary shell.

3. The biaxially retractable feeding, stirring, and friction processing device according to claim 1, characterized in that, The housing contains a first ball spline screw and a second ball spline screw that drive the stirring needle and the shearing sleeve respectively. The first ball spline screw consists of a first lead screw and a first ball nut and a first ball spline mounted on the first lead screw, and the first ball nut and the first ball spline are rotatably connected to the housing. The second ball spline screw consists of a hollow second lead screw and a second ball nut and a second ball spline mounted on the second lead screw, and the second ball nut and the second ball spline are rotatably connected to the housing. The first ball nut, the first ball spline, the second ball nut, and the second ball spline are each connected to a motor through a gear transmission mechanism, and the motor is mounted on the housing.

4. The biaxially retractable feeding, stirring, and friction processing device according to claim 3, characterized in that, The bottom end of the second lead screw is connected to the shearing sleeve through a sleeve connector, and the bottom end of the first lead screw extends through the second lead screw into the sleeve connector and is connected to the stirring needle through a connecting cap.

5. A multi-position welding or additive manufacturing method using the biaxially retractable feeding and stirring friction processing device as described in claim 4, characterized in that, The differential rotation of the motor causes the first and second ball spline screws to drive the stirring needle and the shearing sleeve to perform axial movement, rotational movement, and combined movement, respectively. The material is fed into the spiral groove through the feeding hole and pre-formed into a spring shape. The rotating spring-shaped wire is then screwed into the shearing sleeve and continuously fed to the arc-shaped needle groove on the bottom end face of the shearing sleeve. Through the extrusion and shearing of the arc-shaped needle groove on the bottom end face of the shearing sleeve, and the high-speed rotation of the stirring needle for stirring and friction, multi-position continuous additive manufacturing or non-thinning welding is achieved.

6. A vibration control method for the biaxial retractable feeding and stirring friction processing device according to claim 2, characterized in that, Includes the following steps: a. Install and connect a six-dimensional force sensor to detect the axial force F of the spindle in real time. Z Forward resistance F XY ; b. Install exciters 0-4, and use them in conjunction with exciters 1-4 to excite vibration in any direction on the horizontal plane of the main shaft. Exciter 0 excites vibration in the direction perpendicular to the horizontal plane of the main shaft. c. In actual solid-state stirring processes, an auxiliary vibrator is used to obtain the optimal vibrator power P1 and the optimal stress range F of the structural region through the microstructure and mechanical properties. XY1 -F XY2 and F Z1 -F Z2 This enables solid-phase mixing of high-quality structures; d. For harder materials where smooth control is difficult, the force F during solid-state stirring can be monitored in real time. XY and F Z The magnitude and direction of the resultant force are determined. When the force exceeds the optimal force range, the power of the optimal exciter is increased, and when the force is below the optimal force range, the power of the optimal exciter is decreased. The goal is to achieve compliant control of the solid-phase stirring process.

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