A laser additive repair machine and repair method

Abstract

The application discloses a kind of laser additive repair machines and repair methods, the laser additive repair machine includes sealed cabin, first vacuum device, heating fixture table, mechanical arm and repair device;Sealed cabin is provided with first air outlet;First vacuum device is communicated sealed cabin by first air outlet;Heating fixture table is arranged in sealed cabin, and heating fixture table is used to fix and heat workpiece;Mechanical arm is arranged in sealed cabin;Repair device includes mounting table, laser mechanism and wire feeding mechanism, mounting table is connected at one end of mechanical arm, and laser mechanism and wire feeding mechanism are all arranged on mounting table, and mechanical arm is used to drive wire feeding mechanism and laser mechanism to be close to workpiece on heating fixture table, and wire feeding mechanism is used to deliver repair wire to workpiece, and laser mechanism is used to emit laser to repair wire.The laser additive repair machine of the application can improve the repair environment, reduce the thermal stress of workpiece and repair wire, and improve the repair quality.

Description

Technical Field

[0001] This invention relates to the field of metal repair, and in particular to a laser additive repair machine and repair method. Background Technology

[0002] Laser repair technology is an advanced manufacturing technique that uses a high-energy laser beam to clad repair materials to repair localized defects such as cracks, pits, and wear on the surface of workpieces. This technology is widely used in the remanufacturing and repair of high-value components in aerospace, mold manufacturing, and precision machinery industries.

[0003] In existing laser repair equipment and methods, repair operations are typically performed in an atmospheric environment. However, reactive gases such as oxygen and water vapor in the atmosphere react with the molten metal in the high-temperature molten pool, generating oxide inclusions. This leads to defects such as porosity and slag inclusions within the repair layer, reducing its density and mechanical properties. Furthermore, during the repair process, laser heating only acts on a localized area, while the workpiece itself remains at a relatively low temperature. This results in a significant temperature gradient between the molten pool and the substrate. This uneven temperature field generates substantial thermal stress, easily inducing microcracks in the repair layer or heat-affected zone, and even causing the workpiece itself to crack, leading to unstable repair quality. Moreover, the commonly used repair wire is fed into the molten pool at room temperature, while the workpiece substrate is relatively cold. The significant temperature difference between the two at the moment of fusion further exacerbates the non-equilibrium solidification process of the molten pool, hindering the formation of a uniform and firmly bonded repair layer. Summary of the Invention

[0004] This invention aims to at least solve one of the technical problems existing in the prior art. To this end, this invention proposes a laser additive repair machine that can improve the repair environment, reduce thermal stress on the workpiece and repair wire, and improve repair quality.

[0005] The present invention also proposes a repair method applicable to the aforementioned laser additive repair machine.

[0006] According to a first aspect of the present invention, a laser additive repair machine is used to repair a workpiece using a repair filament. The laser additive repair machine includes: a sealed chamber with a first air extraction port; a first vacuum device connected to the sealed chamber through the first air extraction port; a heating fixture platform disposed within the sealed chamber for fixing and heating the workpiece; a robotic arm disposed within the sealed chamber; and a repair device including a mounting platform, a laser mechanism, and a filament feeding mechanism. The mounting platform is connected to one end of the robotic arm, and both the laser mechanism and the filament feeding mechanism are disposed on the mounting platform. The robotic arm is used to move the filament feeding mechanism and the laser mechanism closer to the workpiece on the heating fixture platform. The filament feeding mechanism is used to deliver the repair filament to the workpiece, and the laser mechanism is used to emit a laser beam onto the repair filament.

[0007] According to the first aspect of the present invention, the laser additive repair machine has at least the following technical effects: the sealed chamber provides a closed and controlled process environment; by evacuating the sealed chamber through the first vacuum device, a low-oxygen, low-humidity vacuum or near-vacuum environment is created, which inhibits the oxidation reaction of the molten pool from the source, avoids the formation of oxide inclusions and pores, and makes the repair layer more dense and pure. Furthermore, the vacuum environment effectively reduces the scattering and absorption loss of laser energy, improves the utilization efficiency and heating stability of laser energy, thereby improving the repair effect; the heating fixture stage can preheat the workpiece before laser repair, significantly reducing the temperature difference between the workpiece substrate and the laser-heated molten pool. The gradient effect, especially for repair work where the repair material and the workpiece material are the same, can significantly reduce the thermal shrinkage stress during the cooling process, effectively preventing cold or hot cracks in the repair layer and heat-affected zone. Preheating can also promote the escape of harmful gases such as hydrogen from the molten pool, further reducing the sensitivity to delayed cracks and improving the repair effect. Using a multi-joint robotic arm as the motion actuator, it can flexibly drive the laser mechanism and wire feeding mechanism to perform multi-degree-of-freedom motion in the sealed chamber, accurately tracking and repairing complex defects at any position on the workpiece. Compared with traditional gantry cranes or three-axis platforms, the robotic arm can easily achieve the repair of complex geometric features such as spatial curves, inclined surfaces, inner walls, and corners.

[0008] According to some embodiments of the present invention, the wire feeding mechanism includes a wire feeding motor, a rotating wheel, a pressure wheel, and a clamping assembly. The wire feeding motor and the clamping assembly are both disposed on the mounting platform. The wire feeding motor is drivenly connected to the rotating wheel, and the clamping assembly is movably connected to the pressure wheel. The circumferential surfaces of the rotating wheel and the pressure wheel are arranged opposite to each other. The circumferential surface of the rotating wheel is used to abut one side of the repair wire, and the circumferential surface of the pressure wheel is used to abut the other side of the repair wire. The clamping assembly is used to move the pressure wheel closer to the rotating wheel, and the wire feeding motor is used to drive the rotating wheel to rotate, thereby delivering the repair wire.

[0009] According to some embodiments of the present invention, the clamping assembly includes a clamping connecting seat, a clamping slider, and a clamping elastic element. The clamping connecting seat is disposed on the mounting platform and is provided with a clamping groove. The clamping slider is slidably connected in the clamping groove. One end of the clamping elastic element is connected to the clamping connecting seat, and the other end of the clamping elastic element is connected to the clamping slider. The pressure roller is rotatably connected to the clamping slider, and the clamping elastic element is used to drive the pressure roller toward the rotating wheel through the clamping slider.

[0010] According to some embodiments of the present invention, the wire feeding mechanism further includes a vibration assembly, a wire feeding belt, a first wire feeding pulley, a second wire feeding pulley, and a wire feeding bearing. The outer ring of the wire feeding bearing is disposed on the mounting platform, the inner ring of the wire feeding bearing is fixedly connected to the first wire feeding pulley, the inner sidewall of the first wire feeding pulley is fixedly connected to the vibration assembly, the wire feeding motor is drivenly connected to the second wire feeding pulley, the wire feeding belt is sleeved on the first wire feeding pulley and the second wire feeding pulley, and the rotating wheel is fixedly connected to the end of the vibration assembly.

[0011] According to some embodiments of the present invention, the wire feeding mechanism further includes a front guide tube and a rear guide tube, both of which are disposed on the mounting platform. The inlet of the front guide tube is used for the repair wire to enter. The opposing surfaces of the rotating wheel and the pressure wheel are used to jointly clamp and deliver the repair wire exiting from the front guide tube. The inlet of the rear guide tube is used to receive the repair wire that is clamped and delivered by the opposing surfaces of the rotating wheel and the pressure wheel. The laser mechanism is used to emit a laser to the repair wire exiting from the rear guide tube.

[0012] According to some embodiments of the present invention, the laser additive repair machine further includes a second vacuum device, and the sealed chamber is also provided with a second air extraction port, the second vacuum device being connected to the sealed chamber through the second air extraction port.

[0013] According to some embodiments of the present invention, three heating fixtures are provided: the first heating fixture is provided on the inner bottom surface of the sealed chamber, the second heating fixture is provided on the inner side surface of the sealed chamber, and the third heating fixture is provided on the inner top surface of the sealed chamber.

[0014] According to some embodiments of the present invention, the laser additive repair machine further includes a door and a sealing assembly. A workpiece inlet and outlet are provided on one side of the sealed chamber. The door is hinged to the outer side wall of one side of the sealed chamber. The sealing assembly is disposed on the outer side wall of one side of the sealed chamber. The door is used to close the workpiece inlet and outlet, and the sealing assembly is used to abut against and press against the door.

[0015] According to a second aspect of the present invention, the repair method is applied to the aforementioned laser additive repair machine. The repair method includes the following steps: opening the sealed chamber and fixing the workpiece on the heating fixture table; closing the sealed chamber, evacuating the sealed chamber with a first vacuum device, and heating the workpiece on the heating fixture table; a robotic arm driving a wire feeding mechanism and a laser mechanism to approach the workpiece, the wire feeding mechanism delivering the repair wire to the workpiece, and the laser mechanism emitting a laser beam onto the repair wire, thereby causing the repair wire to be fused onto the workpiece.

[0016] The repair method according to the second aspect of the present invention has at least the following technical effects: it can easily and conveniently repair workpieces, and the repair environment is a vacuum environment, the workpiece is preheated on the heating fixture table, and the final repair effect is better.

[0017] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0018] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which: Figure 1 This is a schematic diagram of the overall assembly of the laser additive repair machine according to an embodiment of the present invention; Figure 2 for Figure 1 The diagram shows the overall assembly of the laser additive repair machine from another perspective. Figure 3 for Figure 1 The diagram shows the structure of the laser additive repair machine after removing part of the sealed chamber sidewall and components on the sidewall. Figure 4 for Figure 3 The enlarged view of point A on the laser additive repair machine shown; Figure 5 for Figure 3 The diagram shows a structural schematic of the laser additive repair machine from another perspective. Figure 6 for Figure 3 A schematic diagram of the overall assembly of the repair device for the laser additive repair machine shown. Figure 7 for Figure 6 An enlarged view of repair device B shown; Figure 8 for Figure 6 A schematic diagram of the overall assembly of the repair device from another perspective.

[0019] Figure label: Sealed chamber 100, first vent 110, second vent 120, door 130, sealing assembly 140; First vacuum pumping device 210, second vacuum pumping device 220; Heating fixture table 300; Robotic arm 400; Repair device 500, mounting platform 510, laser mechanism 520; Wire feeding mechanism 600, wire feeding motor 610, rotating wheel 620, pressure wheel 630; Clamping assembly 640, clamping connecting seat 641, clamping slide 641a, clamping slider 642, clamping elastic element 643, clamping rotating shaft 644, clamping bearing 645; Vibration assembly 650, first wire feeding pulley 660, wire feeding bearing 670; Front guide tube 681, rear guide tube 682; 700 wire storage and feeding machine. Detailed Implementation

[0020] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0021] In the description of this invention, it should be understood that the directional descriptions, such as "up," "down," "front," "back," "left," "right," "vertical," "horizontal," "top," "bottom," "point," "inner," "outer," "axial," "radial," "circumferential," and "around," are based on the directional or positional relationships shown in the accompanying drawings and are only for the convenience of describing the invention and simplifying the description. They 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, and therefore should not be construed as a limitation of the invention. In the description of this invention, sidewalls refer to the left side wall and / or the right side wall.

[0022] In the description of this invention, "a plurality of" means two or more; "greater than," "less than," "exceeding," etc., are understood to exclude the number itself; and "above," "below," "within," etc., are understood to include the number itself. Where "first" or "second" is used, it is only for the purpose of distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the number of indicated technical features, or implicitly indicating the sequential relationship of the indicated technical features.

[0023] In the description of this invention, it should be understood that "A is set on B" or "A is set on B" describes the connection or positional relationship between A and B, and does not mean that A is necessarily above B.

[0024] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, movable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium; and they can refer to the internal communication of two components. In some embodiments, "bolted connection" and "screw connection" can be used interchangeably. Those skilled in the art can understand the specific meaning of the above terms in this invention in conjunction with the specific circumstances. It should be understood that multiple similar features in this invention are only distinguished by different prefixes. Therefore, in this invention, the feature names without distinguishing prefixes (or feature names with partial prefixes) are used to represent the combination of similar features of this type, such as using "wheel" to represent pressure wheel 630 and rotating wheel 620.

[0025] Reference Figure 1 , Figure 2 and Figure 5 According to an embodiment of the present invention, a laser additive repair machine is used to repair workpieces using repair wire. The laser additive repair machine includes a sealed chamber 100, a first vacuum device 210, a heating fixture 300, a robotic arm 400, and a repair device 500. The laser additive repair machine is used to repair defects (such as cracks, dents, etc.) on workpieces using repair wire. The repair work differs from general welding work. The material of the repair wire is not necessarily welding wire, but may be other objects. Specifically, the material of the repair wire is generally the same as the workpiece material, or has better performance than the workpiece material, so that the performance of the repaired workpiece is as similar as possible to or even better than that of the workpiece without defects.

[0026] The sealed chamber 100 is equipped with a first vent 110. The sealed chamber 100 is roughly rectangular in shape, and its interior also has a roughly rectangular cavity, or in other words, the sealed chamber 100 is enclosed by six plates (front, back, left, right, top, and bottom). In addition to the vent, the sealed chamber 100 can also have other openings, such as cable inlet / outlet openings, cooling water inlet / outlet openings, protective gas inlet / outlet openings, etc., or each equipment component can have a dedicated opening for connecting external components, and other spare openings can also be provided. Some openings can be closed when not in use.

[0027] The first vacuum device 210 is connected to the sealed chamber 100 through the first air extraction port 110. Specifically, the vacuum device can be various types of vacuum pumps and their auxiliary components (such as pressure gauges, air filter components, etc.); the vacuum device can extract the air from the sealed chamber 100, thereby creating a vacuum environment within the sealed chamber 100 as much as possible, which is beneficial for the workpiece cladding repair work, avoids oxygen affecting and oxidizing the workpiece, significantly reduces or even completely eliminates pores and voids in the weld, improves the density of the weld, and makes the workpiece heating more uniform and stable.

[0028] A heating fixture table 300 is disposed within a sealed chamber 100 and is used to fix and heat a workpiece. The heating fixture table 300 may be equipped with a heating assembly to heat the workpiece; specifically, for example, a heating wire may be used. The heating fixture table 300 itself is a metal component; the heating wire heats the heating fixture table 300, which then conducts the heat to the workpiece, thus heating it. The heating fixture table 300 is equipped with at least two clamping blocks, all of which are connected to the heating fixture table 300. At least one clamping block is movably connected to the heating fixture table 300, allowing the workpiece to be clamped and fixed using the two clamping blocks. The clamping blocks may be part of the heating fixture table 300 or independent components, and may be manually moved, fixed, or clamped by other mechanical equipment.

[0029] A robotic arm 400 is housed within the sealed chamber 100. The robotic arm 400 is a multi-joint robotic arm capable of moving a repair device 500 connected to one end in three-dimensional space and adjusting the attitude angle of the repair device 500, thereby enabling the repair device 500 to perform wire cladding repair on defects in any part of the workpiece. Specifically, the robotic arm 400 can be, for example, a six-axis robotic arm with six degrees of freedom (movement along the X-axis, movement along the Y-axis, movement along the Z-axis, rotation around the X-axis, rotation around the Y-axis, and rotation around the Z-axis), thus facilitating the movement of the repair device 500 to repair defects in most or even any location on the workpiece.

[0030] The repair device 500 includes a mounting platform 510, a laser mechanism 520, and a wire feeding mechanism 600. The mounting platform 510 (rotatably) is connected to one end of a robotic arm 400. Both the laser mechanism 520 and the wire feeding mechanism 600 are mounted on the mounting platform 510. The robotic arm 400 is used to move the wire feeding mechanism 600 and the laser mechanism 520 closer to the workpiece on the heating fixture 300. The wire feeding mechanism 600 is used to deliver the repair wire to the workpiece, and the laser mechanism 520 is used to emit a laser beam towards the repair wire (the end closest to the workpiece). The laser mechanism 520 can be a Jiaqiang BF06K oscillating laser welding head, which generally includes a laser generator, a recognition camera, an oscillation assembly, and other components, and also has various interfaces for connecting auxiliary substances such as cooling water and protective gas. The laser mechanism 520 emits a laser to the repair wire, causing the repair wire to melt (at least partially melt) and enter the defect area of ​​the workpiece, thereby repairing the workpiece defect; in some embodiments, a portion of the laser emitted by the laser mechanism 520 will also irradiate the workpiece (defect), thereby further heating or even completely melting a portion of the workpiece, thereby enhancing the repair effect.

[0031] The laser additive repair machine of this invention provides a closed and controlled process environment through a sealed chamber 100. A first vacuum device 210 evacuates the sealed chamber 100, creating a low-oxygen, low-humidity vacuum or near-vacuum environment. This inhibits oxidation of the molten pool from the source, preventing the formation of oxide inclusions and pores, resulting in a denser and purer repair layer. Furthermore, the vacuum environment effectively reduces laser energy scattering and absorption losses, improving laser energy utilization efficiency and heating stability, thereby enhancing the repair effect. The heating fixture 300 preheats the workpiece before laser repair, significantly reducing the temperature gradient between the workpiece substrate and the laser-heated molten pool, especially beneficial for repair applications. Repair work using materials identical to those of the workpiece can significantly reduce thermal shrinkage stress during the cooling process, effectively preventing cold or hot cracks in the repair layer and heat-affected zone. Preheating also promotes the escape of harmful gases such as hydrogen from the molten pool, further reducing the sensitivity to delayed cracks and improving the repair effect. Using a multi-joint robotic arm 400 as the motion actuator, it can flexibly drive the laser mechanism 520 and the wire feeding mechanism 600 to perform multi-degree-of-freedom movements within the sealed chamber 100, accurately tracking and repairing complex defects at any position on the workpiece. Compared with traditional gantry cranes or three-axis platforms, the robotic arm 400 can easily achieve the repair of complex geometric features such as spatial curves, inclined surfaces, inner walls, and corners.

[0032] It should be understood that the vacuum pumping device, robotic arm 400, laser mechanism 520, etc. are all commonly used components in existing technologies. Their specific composition, structure, connection, working process, working principle, etc. can all be referred to the existing technology content, and will not be repeated here.

[0033] Reference Figure 4 , Figure 6 and Figure 7 In some embodiments of the present invention, the wire feeding mechanism 600 includes a wire feeding motor 610, a rotating wheel 620, a pressure wheel 630, and a pressing assembly 640. The wire feeding motor 610 and the pressing assembly 640 are both mounted on the mounting platform 510. The wire feeding motor 610 is driven to the rotating wheel 620 (through an intermediate transmission assembly). The pressing assembly 640 is movably connected to the pressure wheel 630. The circumferential surfaces of the rotating wheel 620 and the pressure wheel 630 are arranged opposite to each other. The circumferential surface of the rotating wheel 620 is used to abut one side of the repair wire, and the circumferential surface of the pressure wheel 630 is used to abut the other side of the repair wire. The pressing assembly 640 is used to move the pressure wheel 630 closer to the rotating wheel 620. The wire feeding motor 610 is used to drive the rotating wheel 620 to rotate, thereby (driving the repair wire to move) delivering the repair wire.

[0034] The circumferential surface of the wheel, similar to a circular surface, is the curved or outer circumferential surface of the wheel, roughly equivalent to the circumferential or curved surface of a cylinder. One side of the repair wire abuts against the circumferential surface of the rotating wheel 620, and the other side abuts against the circumferential surface of the pressure wheel 630. The clamping assembly 640 moves the pressure wheel 630 closer to the rotating wheel 620, thereby applying pressure to the repair wire. The wire feeding motor 610 drives the rotating wheel 620 to rotate, and the repair wire is driven and delivered to the workpiece due to the frictional force of the rotating wheel 620. The pressure wheel 630 rotates passively, thereby reducing the frictional force between the pressure wheel 630 and the repair wire, and not hindering the movement and delivery of the repair wire. The connection between the wire feeding motor 610 and the rotating wheel 620 can be a direct connection, that is, the rotating wheel 620 is directly connected to the output shaft of the wire feeding motor 610; or it can be an indirect connection through an intermediate transmission assembly, such as through a belt or pulley; the connection of other similar components is similar.

[0035] Reference Figure 6 and Figure 7 In some embodiments of the present invention, the clamping assembly 640 includes a clamping connecting seat 641, a clamping slider 642, and a clamping elastic member 643. The clamping connecting seat 641 is disposed on the mounting platform 510 and is provided with a clamping groove 641a. The clamping slider 642 is slidably connected in the clamping groove 641a. One end of the clamping elastic member 643 is connected to the clamping connecting seat 641, and the other end of the clamping elastic member 643 is connected to the clamping slider 642. The pressure roller 630 is rotatably connected to the clamping slider 642. The clamping elastic member 643 is used to move the pressure roller 630 closer to the rotating wheel 620 (or to make it tend to move closer to the rotating wheel 620; the same applies to other similar structures).

[0036] The above settings ensure that the pressure roller 630 and rotating roller 620 apply appropriate pressure to the repair wire, preventing excessive pressure that would cause the repair wire to be completely compressed, making delivery difficult or even impossible; and preventing insufficient pressure that would cause the repair wire to slip, be delivered late, or even fail to be compressed and delivered. The clamping groove 641a extends approximately along the direction close to the rotating roller 620. Specifically, with the central axes of the pressure roller 630 and rotating roller 620 as two reference axes (the two reference axes are approximately parallel), the reference plane includes the two reference axes, and the extension direction of the clamping groove 641a is located within the reference plane and perpendicular to either reference axis. The clamping elastic element 643 can be a spring, disc spring, elastic plastic part, etc.; the specific pressure can be adjusted by replacing the clamping elastic element 643. The pressure roller 630 and the pressure slider 642 are rotatably connected. Specifically, the pressure slider 642 is provided with a pressure shaft 644 (one end of the pressure shaft 644 is fixedly connected to the pressure slider 642), and the other end of the pressure shaft 644 is provided with a pressure bearing 645 (inner ring, or inner ring). The pressure roller 630 is connected to the pressure bearing 645 (outer ring, or outer ring).

[0037] Reference Figure 7 and Figure 8 In some embodiments of the present invention, the wire feeding mechanism 600 further includes a vibration component 650, a wire feeding belt, a first wire feeding pulley 660, a second wire feeding pulley, and a wire feeding bearing 670. The outer ring (outer side wall) of the wire feeding bearing 670 is mounted on the mounting platform 510. The inner ring (inner side wall) of the wire feeding bearing 670 is fixedly connected to the first wire feeding pulley 660 (outer side wall). The inner side wall of the first wire feeding pulley 660 is fixedly connected to the vibration component 650 (outer side wall). The wire feeding motor 610 is driven by the second wire feeding pulley (the wire feeding motor 610 is used to drive the second wire feeding pulley to rotate). The wire feeding belt is sleeved on the first wire feeding pulley 660 and the second wire feeding pulley. The rotating wheel 620 is fixedly connected to the end of the vibration component 650.

[0038] The first wire feeding pulley 660 (vibration assembly 650) is rotatably connected to the mounting platform 510 via the wire feeding bearing 670. The output shaft of the wire feeding motor 610 is connected to the second wire feeding pulley. The wire feeding motor 610 drives the second wire feeding pulley to rotate. The second wire feeding pulley drives the first wire feeding pulley 660 (relative to the mounting platform 510) to rotate together via the wire feeding belt. The first wire feeding pulley 660 drives the vibration assembly 650 to rotate together. The rotating wheel 620 is fixedly connected to the end of the vibration assembly 650. On the one hand, the rotation of the vibration assembly 650 drives the rotating wheel 620 to rotate together. On the other hand, the vibration assembly 650 itself can cause the rotating wheel 620 to undergo high-frequency micro-vibration.

[0039] By setting up the vibration component 650, firstly, the wire feeding resistance can be adjusted, improving the stability and smoothness of wire feeding. The high-frequency micro-amplitude vibration generated by the vibration component 650 is transmitted to the rotating wheel 620 and the repair wire. This vibration causes continuous micro-displacement adjustments between the rotating wheel 620 and the repair wire. Among these micro-displacements, there will always be a more suitable position for the attitude and distance between the rotating wheel 620 and the repair wire, allowing the repair wire to be delivered more smoothly. Secondly, it preheats and removes contaminants from the repair wire. The vibration transmitted to the repair wire allows it to be appropriately preheated, and can remove any small oxide films or oil stains that may be present on the surface of the repair wire. Thirdly, the vibration can also be transmitted to the molten pool and workpiece to a certain extent through the repair wire, thereby promoting the flow and diffusion of molten metal, making the cladding layer (repair layer) spread more evenly and the bonding interface tighter, thus reducing defects such as incomplete fusion, porosity, and slag inclusions. Furthermore, the vibrating repair wire can also break up the oxide film in the molten pool and remove micro-bubbles, further improving the repair effect. Fourth, the convection and oscillation induced by vibration in the molten pool can break up growing primary dendrites and increase the nucleation rate, thereby refining the solidification structure of the repair layer. This grain refinement strengthens the repair layer, improving its strength, plasticity, and fatigue performance, making it more compatible with or even superior to the properties of the base material. Fifth, the mechanical and thermal effects of vibration help homogenize the temperature distribution of the molten pool and promote stress relaxation. Especially for easily cracked materials (such as tungsten steel and nickel-based alloys), vibration-assisted wire feeding can reduce tensile stress during the solidification shrinkage process of the repair layer, thus inhibiting the formation of cold and hot cracks. Multiple wire feed bearings 670 can be provided, with their central axes collinear.

[0040] Reference Figure 7 and Figure 8 In some embodiments of the present invention, the vibration component 650 is an electromagnetic vibration component.

[0041] The vibration component 650 can be specifically selected and configured according to actual conditions. For example, it can be an electromagnetic vibration component, consisting of an electromagnet, an armature, a return spring system, and a control unit. The control unit converts and outputs a unidirectional pulsating current to the electromagnet, attracting the armature to approach repeatedly. The return spring system resets the armature and moves it away from the electromagnet when it is not attracted. The end of the armature is connected to a rotating wheel 620 (or, one end of the armature is cylindrical; the armature and the rotating wheel 620 are integrally formed), thereby driving the rotating wheel 620 to vibrate, and transmitting the vibration to the repair wire through the rotating wheel 620. The vibration component 650 can also be a mechanical vibration component, consisting of a vibration motor, a cam, and a vibration rod. The vibration motor drives the cam to rotate, and the cam and the vibration rod are movably connected, thereby driving the vibration rod to vibrate up and down when the cam rotates. The end of the vibration rod is connected to the rotating wheel 620. The vibration component 650 can also be other forms, such as a piezoelectric vibration component, a magnetostrictive vibration component, or a vibration component with a moving coil vibrating under constant Ampere force and changing current. The first wire feeding pulley 660 can be fixedly connected to the non-vibrating part (electromagnet, cam, etc.) inside the vibration assembly 650; at this time, the non-vibrating part of the vibration assembly 650 can drive the vibrating part inside the vibration assembly 650 to rotate synchronously. Specifically, for example, the two parts can be connected and fixed by a limiting sliding sleeve, so that the vibrating part can slide in the sliding sleeve, and when the limiting sliding sleeve rotates, it drives the two parts to rotate together; or the vibrating part (armature, vibrating rod, etc.) inside the vibration assembly 650 can be slidably connected by a linear bearing or other components.

[0042] Reference Figure 4 and Figure 7 In some embodiments of the present invention, the wire feeding mechanism 600 further includes a front wire guide 681 and a rear wire guide 682. Both the front wire guide 681 and the rear wire guide 682 are mounted on the mounting platform 510 (pressing connection seat 641). The inlet of the front wire guide 681 is used for the repair wire to enter. The opposing surfaces of the rotating wheel 620 and the pressure wheel 630 are used to jointly clamp and deliver the repair wire exiting from the front wire guide 681. The inlet of the rear wire guide 682 is used to receive the repair wire that is clamped and delivered by the opposing surfaces of the rotating wheel 620 and the pressure wheel 630. The laser mechanism 520 is used to emit a laser to the repair wire exiting from the rear wire guide 682.

[0043] The front guide tube 681 and the rear guide tube 682 are provided to guide and correct the repair wire, so that the part of the repair wire that contacts the pressure roller 630 and the rotating roller 620 is as straight as possible, and the repair wire is delivered more smoothly and stably by the wire feeding mechanism 600.

[0044] Reference Figure 2 and Figure 5In some embodiments of the present invention, the laser additive repair machine further includes a second vacuum device 220, and the sealed chamber 100 is also provided with a second air extraction port 120. The second vacuum device 220 is connected to the sealed chamber 100 through the second air extraction port 120.

[0045] The first vacuum pumping device 210 can be a common, existing technology device such as a Roots pump, which can initially evacuate the sealed chamber 100, reducing the load on the second vacuum pumping device 220 and the probability of air contamination. The second vacuum pumping device 220 is a device that can further evacuate the sealed chamber 100 to achieve a higher vacuum level, such as a molecular pump. Generally, after the first vacuum pumping device 210 initially evacuates the sealed chamber 100, the second vacuum pumping device 220 is used to further evacuate it. Specifically, after the second vacuum pumping device 220 completes the evacuation, the air pressure inside the sealed chamber 100 can be reduced to 1×10⁻⁶. -4 Below Pa.

[0046] Reference Figure 3 and Figure 5 In some embodiments of the present invention, three heating fixture tables 300 are provided. The first heating fixture table 300 is provided on the inner bottom surface of the sealed chamber 100, the second heating fixture table 300 is provided on the inner side surface of the sealed chamber 100, and the third heating fixture table 300 is provided on the inner top surface of the sealed chamber 100.

[0047] Three heated clamping tables 300 are set up to clamp and fix large workpiece plates together, or to clamp different parts of the workpiece, so as to facilitate the repair and processing of different surfaces of the workpiece. The robotic arm 400 can flexibly change the posture and position of the repair device 500 to repair and process workpieces in different postures and positions.

[0048] In some embodiments of the present invention, the laser additive repair machine further includes a wire storage and feeding machine 700, which is disposed within the sealed chamber 100 and is used to store and deliver repair wires (to the wire feeding mechanism 600).

[0049] Reference Figure 1 In some embodiments of the present invention, the laser additive repair machine further includes a door 130 and a sealing assembly 140. A workpiece inlet and outlet are provided on one side of the sealed chamber 100. The door 130 is hinged to the outer side wall of one side of the sealed chamber 100. The sealing assembly 140 is provided on the outer side wall of one side of the sealed chamber 100. The door 130 is used to close the workpiece inlet and outlet, and the sealing assembly 140 is used to abut against and press against the door 130.

[0050] To facilitate the loading and unloading of large workpieces, the workpiece inlet / outlet and the hatch 130 are both designed to be relatively large. An observation window can be installed on the hatch 130. Specifically, the sealing assembly 140 can be a quick-release clamp.

[0051] In addition to the vacuum pump, other components can be installed outside the sealed chamber 100, such as an electrical cabinet, a laser cooling water circulation unit, a display screen, a host (or control system), a mouse, and a keyboard. The robotic arm 400, heating components, vacuum pump, and repair device 500 can all be connected to the host and display screen for easy viewing of the actual situation inside the components or the sealed chamber 100, real-time control, and modification of the control program. It should be understood that the laser additive repair machine of this invention can be used for repair experiments in laboratories as well as for workpiece repair work in other factories.

[0052] Reference Figure 1 , Figure 2 and Figure 5 According to the repair method of the present invention, applied to the aforementioned laser additive repair machine, the repair method includes the following steps: Open the sealed chamber 100 and fix the workpiece on the heating fixture table 300; The sealed chamber 100 is sealed, and the first vacuum device 210 evacuates the sealed chamber 100 (inner cavity, internal space) and the heating fixture table 300 heats the workpiece. The robotic arm 400 drives the wire feeding mechanism 600 and the laser mechanism 520 to approach the workpiece. The wire feeding mechanism 600 delivers the repair wire to the workpiece, and the laser mechanism 520 emits a laser to the repair wire, thereby causing the repair wire to be fused onto the workpiece.

[0053] Using the above repair method, the workpiece can be repaired simply and conveniently. The repair environment is a vacuum environment, and the workpiece is preheated on the heating fixture 300, resulting in a better final repair effect.

[0054] The more specific repair method in this embodiment is used to repair a cracked tungsten plate (i.e., the workpiece is a cracked tungsten plate) using tungsten wire (i.e., the repair wire is tungsten wire). The specific steps are as follows: Open the sealed chamber 100 and fix the bottom, side and top of the tungsten plate onto the corresponding heating fixture 300 (the first heating fixture 300, the second heating fixture 300 and the third heating fixture 300). The sealed chamber 100 is sealed, and the first vacuum pumping device 210 evacuates the sealed chamber 100 (inner cavity, internal space) by vacuuming. The second vacuum pumping device 220 evacuates the sealed chamber 100 (inner cavity, internal space) to reduce the air pressure inside the sealed chamber 100 to 1×10⁻⁶. -4 Below Pa; (The heating component heats the tungsten plate via) the heating fixture 300, so that the temperature of the tungsten plate reaches above 900°C; The robotic arm 400 drives the wire feeding mechanism 600 and the laser mechanism 520 to approach one end of the crack in the tungsten plate; The wire feeding mechanism 600 delivers the tungsten wire to one end of the crack on the tungsten plate, and the vibration component 650 drives the tungsten wire to vibrate at a high frequency. The laser mechanism 520 emits a laser towards the tungsten wire (at one end of the crack), thereby causing the tungsten wire to be fused to one end of the crack on the tungsten plate. The robotic arm 400 drives the wire feeding mechanism 600 and the laser mechanism 520 to move along the direction of the crack in the tungsten plate, thereby causing the tungsten wire to continuously melt and repair the crack in the tungsten plate.

[0055] The above-described repair method effectively overcomes the characteristics of tungsten, such as its high melting point and difficulty in melting. The vibration component 650 further enhances the repair effect of the tungsten wire. The tungsten plate can also be replaced with other types of metal, all of which can be repaired using the same method with metal wire.

[0056] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present invention.

Claims

1. A laser additive repair machine for repairing workpieces using repair wire, characterized in that, The laser additive repair machine includes: The sealed chamber is equipped with a first air extraction port; The first vacuuming device is connected to the sealed chamber through the first air extraction port; A heating fixture is disposed within the sealed chamber, and the heating fixture is used to fix and heat the workpiece; A robotic arm is installed inside the sealed chamber; The repair device includes a mounting platform, a laser mechanism, and a wire feeding mechanism. The mounting platform is connected to one end of the robotic arm. The laser mechanism and the wire feeding mechanism are both mounted on the mounting platform. The robotic arm is used to move the wire feeding mechanism and the laser mechanism closer to the workpiece on the heating fixture platform. The wire feeding mechanism is used to deliver the repair wire to the workpiece, and the laser mechanism is used to emit a laser to the repair wire.

2. The laser additive repair machine according to claim 1, characterized in that, The wire feeding mechanism includes a wire feeding motor, a rotating wheel, a pressure wheel, and a clamping assembly. The wire feeding motor and the clamping assembly are both mounted on the mounting platform. The wire feeding motor is driven to the rotating wheel, and the clamping assembly is movably connected to the pressure wheel. The circumferential surfaces of the rotating wheel and the pressure wheel are arranged opposite to each other. The circumferential surface of the rotating wheel is used to abut one side of the repair wire, and the circumferential surface of the pressure wheel is used to abut the other side of the repair wire. The clamping assembly is used to move the pressure wheel closer to the rotating wheel, and the wire feeding motor is used to drive the rotating wheel to rotate, thereby delivering the repair wire.

3. The laser additive repair machine according to claim 2, characterized in that, The clamping assembly includes a clamping connecting seat, a clamping slider, and a clamping elastic element. The clamping connecting seat is disposed on the mounting platform and has a clamping groove. The clamping slider is slidably connected in the clamping groove. One end of the clamping elastic element is connected to the clamping connecting seat, and the other end of the clamping elastic element is connected to the clamping slider. The pressure roller is rotatably connected to the clamping slider, and the clamping elastic element is used to drive the pressure roller toward the rotating wheel through the clamping slider.

4. A laser additive repair machine according to claim 2, characterized in that, The wire feeding mechanism further includes a vibration component, a wire feeding belt, a first wire feeding pulley, a second wire feeding pulley, and a wire feeding bearing. The outer ring of the wire feeding bearing is mounted on the mounting platform, and the inner ring of the wire feeding bearing is fixedly connected to the first wire feeding pulley. The inner sidewall of the first wire feeding pulley is fixedly connected to the vibration component. The wire feeding motor is driven by the second wire feeding pulley. The wire feeding belt is sleeved on the first wire feeding pulley and the second wire feeding pulley. The rotating wheel is fixedly connected to the end of the vibration component.

5. A laser additive repair machine according to claim 4, characterized in that, The vibration component is an electromagnetic vibration component.

6. A laser additive repair machine according to claim 2, characterized in that, The wire feeding mechanism further includes a front wire guide tube and a rear wire guide tube, both of which are mounted on the mounting platform. The inlet of the front wire guide tube is used for the repair wire to enter. The opposing surfaces of the rotating wheel and the pressure wheel are used to jointly clamp and deliver the repair wire exiting from the front wire guide tube. The inlet of the rear wire guide tube is used to receive the repair wire that is clamped and delivered by the opposing surfaces of the rotating wheel and the pressure wheel. The laser mechanism is used to emit a laser to the repair wire exiting from the rear wire guide tube.

7. A laser additive repair machine according to claim 1, characterized in that, The laser additive repair machine also includes a second vacuum device, and the sealed chamber is also provided with a second air extraction port. The second vacuum device is connected to the sealed chamber through the second air extraction port.

8. A laser additive repair machine according to claim 1, characterized in that, The heating fixture platform is provided in three parts: the first heating fixture platform is provided on the inner bottom surface of the sealed chamber, the second heating fixture platform is provided on the inner side surface of the sealed chamber, and the third heating fixture platform is provided on the inner top surface of the sealed chamber.

9. A laser additive repair machine according to claim 1, characterized in that, The laser additive repair machine also includes a door and a sealing assembly. A workpiece inlet and outlet are provided on one side of the sealed chamber. The door is hinged to the outer wall of one side of the sealed chamber. The sealing assembly is provided on the outer wall of one side of the sealed chamber. The door is used to close the workpiece inlet and outlet, and the sealing assembly is used to abut and press against the door.

10. A repair method, applied to the laser additive repair machine according to any one of claims 1 to 9, characterized in that, The repair method includes the following steps: Open the sealed chamber and fix the workpiece on the heating fixture table; The sealed chamber is sealed, the first vacuum device evacuates the sealed chamber, and the heating fixture table heats the workpiece. The robotic arm drives the wire feeding mechanism and the laser mechanism to approach the workpiece. The wire feeding mechanism delivers the repair wire to the workpiece, and the laser mechanism emits a laser to the repair wire, thereby causing the repair wire to be fused onto the workpiece.

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