A laser broadband cladding powder feeder

Abstract

The present invention discloses a broadband laser cladding powder feeding head, comprising a light guide tube, a powder feeding chamber, a powder beam splitter, a cooling water device, a protective gas device, and other components arranged longitudinally in a vertical direction. The broadband laser cladding powder feeding head features a side-blowing protective air curtain, effectively preventing contamination of the laser assembly by cladding smoke and dust. Both the light spot focus position and the powder spot convergence position are adjustable to ensure their overlap, maximizing powder utilization and cladding efficiency. The head also features a self-cooling function, enabling long-term stable operation. It also provides effective gas protection for the laser molten pool, preventing reactions between elements in the molten pool and oxygen in the air, thereby ensuring the performance of the cladding layer.

Description

Technical Field

[0001] The invention relates to a powder feeding head for laser cladding, in particular to a powder feeding head used for laser broadband cladding. Background Art

[0002] At present, with the increase of laser power and the advancement of spot shape modulation devices, the power density and spot shape stability required for broadband laser cladding have been guaranteed. There are many types of existing laser heads, each with its own advantages and disadvantages, but there is still a lack of mature and reliable products for dedicated powder feeding heads for laser broadband cladding. Summary of the Invention

[0003] The object of the present invention is to provide a laser broadband cladding powder feeding head which can effectively ensure the overlap of light spots and powder spots, has a self-cooling function, and can effectively protect the molten pool.

[0004] The technical solution to realize the present invention is:

[0005] The present invention provides a laser broadband cladding powder feeding head, comprising a light guide tube, wherein the upper end inlet of the light guide tube is connected to the light outlet of the laser assembly; a side blowing protective gas interface is provided in the middle of the side wall of the light guide tube;

[0006] An internal thread is provided on the inner wall at the bottom outlet of the light guide cylinder to form an internal threaded hole end, and an external thread is provided on the upper outer wall of a powder feeding chamber to form an external threaded end. The external thread end of the powder feeding chamber is threadedly connected to the internal threaded hole end of the light guide cylinder, and the length of the internal thread at the lower end of the light guide cylinder is greater than the length of the external thread at the upper end of the powder feeding chamber.

[0007] With the vertical center axis of the powder feeding chamber as the axis of symmetry, two positioning support conduits are symmetrically distributed on the upper part of the side wall of the powder feeding chamber and are arranged in a V shape with each other, and threaded holes for positioning are reserved on the side walls of the two positioning support conduits; two fine-adjustment bracket conduits are symmetrically distributed on the side wall of the powder feeding chamber located below the two positioning support conduits and are arranged in a V shape with each other, and a bracket lock nut is fixed on the upper part of each fine-adjustment bracket conduit, and the bottoms of the two positioning support conduits and the two fine-adjustment bracket conduits are respectively connected to the openings on the side wall of the powder feeding chamber;

[0008] A powder cluster diverter is connected to each of the two positioning support guide tubes, and each powder cluster diverter includes a powder cluster tube, and the powder cluster tube includes a circular copper tube body, the lower end of the circular copper tube body is a flat structure to form a flat-mouthed outlet section, and the upper side of the circular copper tube body is bent to form a bending section that is consistent with the inclination angle of the positioning support guide tube, the lower end of the adjusting stud whose inclination angle is consistent with the inclination angle of the fine-tuning bracket guide tube is welded to the copper tube body, a limit plate is fixed at the bending part of the circular copper tube body, a rotating shaft positioning seat is fixed on the upper outer wall of the bending section, and a rotating shaft positioning seat is fixed on the rotating shaft positioning seat. A positioning hole is opened, and the pressure plate and the diverter plate are fixedly connected up and down to form a diverter device, the diverter plate is a convex structure, the convex top surface of the convex structure is arranged in contact with the bottom wall of the pressure plate, and multiple powder channels are opened on the convex top surface of the convex structure, and the multiple powder channels are arranged in a divergent radial shape from the inlet side to the outlet side. A powder outlet connected to the outlet side of the multiple powder channels is formed between the pressure plate and the diverter plate located below the multiple powder channels, and a powder feeding port connected to the inlet side of the multiple powder channels is formed between the pressure plate and the diverter plate located above the multiple powder channels, and the flat-mouthed outlet section is inserted into the powder feeding port and fixedly connected;

[0009] The adjusting stud of each powder cluster diverter is inserted into the corresponding fine-tuning bracket guide tube and is threadedly connected to the bracket lock nut on the fine-tuning bracket guide tube, and the bending section of each powder cluster diverter is inserted into the corresponding positioning support guide tube, the rotating shaft positioning seat and the positioning support guide tube are clearance-matched, the rotating shaft positioning seat and the positioning support guide tube are fixedly connected by bolts passing through the threaded hole and the positioning hole, and the limiting plate can be fitted with the inner wall of the powder feeding chamber, the central axis of the limiting plate coincides with the central axis of the positioning support guide tube on the corresponding side, the powder outlet of each powder cluster diverter is connected to the bottom outlet of the powder feeding chamber, a cooling water device is fixed on the outer wall of the lower part of the powder feeding chamber, the protective gas device is arranged at the bottom outlet of the powder feeding chamber and is fixedly connected to the cooling water device by bolts, the protective gas device includes an annular air cavity, the middle hole of the annular air cavity is coaxially arranged with the bottom outlet of the powder feeding chamber, and the annular air cavity is connected to the air inlet pipe.

[0010] The significant advantages of the present invention are: it has a side-blowing protective air curtain to effectively prevent the laser component from being contaminated by cladding smoke and dust; the light spot focusing position and the powder spot convergence position are adjustable to ensure that the two coincide, thereby maximizing the powder utilization rate and cladding efficiency; the powder feeding head has a self-cooling function and can work stably for a long time; it can effectively provide gas protection for the laser molten pool to prevent the elements in the molten pool from reacting with oxygen in the air, thereby ensuring the performance of the cladding layer. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1This is a schematic structural diagram of a powder feeding head for wide-band laser cladding according to the present invention;

[0012] Figure 2 for Figure 1 A schematic structural diagram of the light guide tube in the structure shown;

[0013] Figure 3 for Figure 1 A schematic diagram of the structure of the powder feeding chamber in the structure shown;

[0014] Figure 4 Schematic diagram of the structure of the powder beam splitter.

[0015] Figure 5 is a schematic structural diagram of a pressing plate;

[0016] Figure 5-1 It is the front view of the pressure plate;

[0017] Figure 5-2 It is the left view of the pressure plate;

[0018] FIG6 is a schematic structural diagram of a powder diverter plate;

[0019] Figure 6-1 It is a front view of the powder diverter plate;

[0020] Figure 6-2 This is the left view of the powder diverter plate;

[0021] Figure 7 It is a structural diagram of the cooling water device;

[0022] FIG8 is a schematic structural diagram of a protective gas device;

[0023] Figure 8-1 An air cavity for a protective gas device;

[0024] Figure 8-2 An air inlet pipe for the protective gas device;

[0025] Figure 8-3 It is the air outlet of the protective gas device. DETAILED DESCRIPTION

[0026] The present invention is described in further detail below with reference to the accompanying drawings.

[0027] As attached Figure 1 As shown, a laser broadband cladding powder feeding head of the present invention includes a light guide tube 1, and the upper end inlet of the light guide tube is connected to the light outlet of the existing laser component. The connection method can be threaded connection, or other connection methods such as snap fasteners, positioning pins, screws, etc. can be used.

[0028] A side-blowing protective gas interface 5 is opened in the middle of the side wall of the light guide tube. Side-blowing protective gas with a certain pressure and flow rate (preferably argon, but other gases such as nitrogen and compressed air can also be used) can enter the light guide tube through the side-blowing protective gas interface to form a side-blowing protective gas curtain to prevent the smoke and dust generated during laser cladding from entering the laser component upward with the airflow.

[0029] The inner wall at the bottom exit of the light guide is provided with internal threads, forming an internally threaded hole. The upper outer wall of a powder feeding chamber 2 is provided with external threads, forming an externally threaded end. The externally threaded end of the powder feeding chamber 2 is threadedly connected to the internally threaded hole of the light guide. The internal threads at the lower end of the light guide are longer than the external threads at the upper end of the powder feeding chamber, allowing the vertical height of the powder feeding chamber relative to the light guide to be adjusted by the length of the threaded engagement.

[0030] Two positioning support conduits 3 are symmetrically arranged in a V-shape on the upper sidewall of the powder feeding chamber, with the vertical center axis of the chamber as the axis of symmetry. Positioning threaded holes 3-1 are reserved in the sidewalls of the two positioning support conduits. Two fine-adjustment support conduits 4 are symmetrically arranged in a V-shape on the sidewall of the powder feeding chamber, located below the two positioning support conduits. A support lock nut is secured to the upper portion of each fine-adjustment support conduit. The bottoms of the two positioning support conduits and the two fine-adjustment support conduits are connected to openings in the sidewall of the powder feeding chamber.

[0031] Each of the two positioning support conduits 3 is connected to a powder cluster diverter, as shown in the attached Figure 4As shown, each powder clustering diverter includes a powder clustering tube 6-3, which includes a circular copper tube body. The lower end of the circular copper tube body is a flat structure forming a flat-mouthed outlet section, and the upper side of the circular copper tube body is bent to form a bent section that is consistent with the inclination angle of the positioning support guide tube 3. The lower end of the adjustment stud 6-4, whose inclination angle is consistent with the inclination angle of the fine-tuning support guide tube 4, is welded to the copper tube body. A limit plate 6-5 is fixed to the bend of the circular copper tube body. A rotating shaft positioning seat 6-6 is fixed to the upper outer wall of the bending section, and a positioning hole 6-7 is opened in the rotating shaft positioning seat 6-6. The pressure plate 6-1 and the diverter plate 6-2 are fixedly connected up and down to form a diverter device. The diverter plate 6-2 is a convex structure. The raised top surface of the convex structure is arranged in contact with the bottom wall of the pressure plate 6-1. Multiple powder channels are opened on the raised top surface of the convex structure. The multiple powder channels are arranged in a divergent radial shape from the inlet side to the outlet side. A powder outlet connected to the outlet side of the multiple powder channels is formed between the pressure plate 6-1 and the diverter plate 6-2 located below the multiple powder channels. A powder feeding port connected to the inlet side of the multiple powder channels is formed between the pressure plate 6-1 and the diverter plate 6-2 located above the multiple powder channels. The flat-mouthed outlet section is inserted into the powder feeding port and is fixedly connected.

[0032] The adjusting stud 6-4 of each powder cluster diverter is inserted into the corresponding fine-tuning bracket catheter 4 and is threadedly connected to the bracket lock nut on the fine-tuning bracket catheter. The bending section of each powder cluster diverter is inserted into the corresponding positioning support catheter 3. The rotating shaft positioning seat 6-6 is clearance-matched with the positioning support catheter 3. The rotating shaft positioning seat 6-6 and the positioning support catheter 3 are fixedly connected by bolts passing through the threaded hole 3-1 and the positioning hole 6-7. The limiting plate 6-5 can be fitted with the inner wall of the powder feeding chamber. The central axis of the limiting plate 6-5 coincides with the central axis of the positioning support catheter 3 on the corresponding side. The powder outlet of each powder cluster diverter is connected to the bottom outlet of the powder feeding chamber.

[0033] The pressure plate and diverter plate (see Figures 5 and 6) are used to divert the powder transported from the powder bundle tube into multiple beams to form a wide-band powder spot. Radial, independent powder channels are processed on the diverter plate, which are called diverter holes. In the attached figure, the powder is divided into 5 paths. In actual application, the powder can be divided into N paths according to the powder spot size requirements to be achieved, and the aperture of the powder channel can also be set as needed. The pressure plate and the diverter plate are matched, and after the upper and lower parts are buckled together, they are connected as a whole by welding. The flat-mouthed outlet section at the front end of the powder bundle tube is inserted into the diverter device, and the powder bundle tube and the diverter device are fixed together by welding to ensure airtightness.

[0034] The adjusting stud, limit plate, and shaft locating seat are used to fix and adjust the position of the powder cluster tube. The adjusting stud is welded to the powder cluster tube, and its distance from the lower outlet of the powder cluster tube can be flexibly adjusted according to the actual size of the powder spot.

[0035] During installation, the powder cluster diverter is simultaneously inserted into the positioning support conduit 3 and the fine-tuning support conduit 4 from within the powder feeding chamber. The bent section of the powder cluster tube is inserted into the positioning support conduit 3, and the adjustment stud 6-4 is inserted into the fine-tuning support conduit 4. The bent section is inserted into the positioning hole 6-7 reserved on the rotating shaft positioning seat, which is concentric with the threaded hole 3-1 on the side wall of the positioning support. At this point, a bolt is passed through the positioning hole 6-7 and the threaded hole 3-1 to connect the positioning support to the powder cluster diverter. The adjustment stud is inserted into the bracket lock nut on the fine-tuning support conduit and connected by threads. The adjustment bracket lock nut can control the adjustment stud to be screwed in and out of the powder feeding chamber, thereby adjusting the angle of the powder cluster diverter. The limit plate can play a positioning role and limit the adjustment angle of the powder cluster diverter. When the adjustment stud is screwed into the powder feeding chamber too far, the limit plate will contact the inner wall of the powder feeding chamber, forming a reaction force to prevent the powder cluster diverter from tilting too much toward the centerline of the powder feeding chamber.

[0036] As attached Figure 1 , Attachment Figure 7 As shown, a cooling water device 7 is fixed to the outer wall of the lower portion of the powder feeding chamber in a ring-shaped manner. It is fixed to the outer wall of the lower end of the powder feeding chamber by welding. The purpose of adopting this connection method is to achieve optimal thermal conductivity between the cooling water device and the powder feeding chamber. The cooling water device has a cavity, which is respectively connected to the water inlet pipe and the water outlet pipe.

[0037] As attached Figure 1 、 Figure 8-1 、 8-2 As shown in Figures 8-3, the protective gas device 8 is arranged at the bottom outlet of the powder feeding chamber and is fixedly connected to the cooling water device by bolts. The protective gas device includes an annular air cavity 8-1. The middle hole of the annular air cavity 8-1 is coaxially arranged with the bottom outlet of the powder feeding chamber. Preferably, the outer diameter of the annular air cavity is more than 1.5 times the long side of the laser beam. The annular air cavity 8-1 is connected to the air inlet pipe 8-2. Preferably, the diameter of the air inlet pipe 8-2 is greater than 6mm to ensure a larger air intake flux. A plurality of air outlet holes 8-3 are provided on the bottom wall of the annular air cavity 8-1. Preferably, the diameter of the air outlet holes is not greater than 1.5mm. The purpose is to ensure that the protective gas flow is discharged more evenly from each air outlet hole, forming an effective multiple protective air curtain around the laser molten pool.

[0038] The outer contour of the protective gas device is generally annular, and may also be in other shapes such as circular or rectangular.

[0039] The operating process of this device is as follows: Before use, move the broadband laser cladding head so that it is positioned above the workpiece to be clad, which is placed on a workbench. Adjust the height of the powder feeding chamber relative to the light guide so that the diameter of the powder spot on the surface of the workpiece to be clad is slightly larger than the diameter of the laser spot. After confirmation, first use a pump to pump cooling water into the cooling water device 7 to form a circulating cooling system; then supply air to the protective gas device 8 to form a protective atmosphere; then open the powder feeder and feed the powder into the powder beam diverter 6; wait for the powder to be evenly ejected from the outlet and pass through the middle hole of the annular air cavity 8-1 before starting the laser cladding process; after the cladding process is completed, close the powder feeder, stop the protective gas supply, and stop the cooling water circulation.

Claims

1. A laser broadband cladding powder feeding head, characterized by: It comprises a light guide tube (1), the upper end inlet of the light guide tube is connected to the light outlet of the laser assembly; a side blowing protective gas interface (5) is provided in the middle of the side wall of the light guide tube; An internal thread is provided on the inner wall at the bottom outlet of the light guide cylinder to form an internal thread hole end, and an external thread is provided on the upper outer wall of a powder feeding chamber (2) to form an external thread end, the external thread end of the powder feeding chamber is threadedly connected to the internal thread hole end of the light guide cylinder, and the length of the internal thread at the lower end of the light guide cylinder is greater than the length of the external thread at the upper end of the powder feeding chamber; With the vertical center axis of the powder feeding chamber as the axis of symmetry, two positioning support conduits (3) are symmetrically distributed on the upper part of the side wall of the powder feeding chamber and are arranged in a V shape with each other, and threaded holes (3-1) for positioning are reserved on the side walls of the two positioning support conduits; two fine-tuning support conduits (4) are symmetrically distributed on the side wall of the powder feeding chamber located below the two positioning support conduits and are arranged in a V shape with each other, a support lock nut is fixed on the upper part of each fine-tuning support conduit, and the bottoms of the two positioning support conduits and the two fine-tuning support conduits are respectively connected to the openings on the side wall of the powder feeding chamber; A powder cluster diverter is connected to each of the two positioning support conduits, and each powder cluster diverter includes a powder cluster tube (6-3). The powder cluster tube includes a circular copper tube body, the lower end of the circular copper tube body is a flat structure forming a flat-mouthed outlet section, and the upper side of the circular copper tube body is bent to form a bending section that is consistent with the inclination angle of the positioning support conduit, the lower end of the adjustment stud (6-4) whose inclination angle is consistent with the inclination angle of the fine-tuning bracket conduit is welded to the copper tube body, a limit plate (6-5) is fixed at the bending part of the circular copper tube body, and a rotating shaft positioning seat (6-6) is fixed on the upper outer wall of the bending section. A positioning hole (6-7) is provided on the seat, and the pressing plate (6-1) and the diverter plate (6-2) are fixedly connected up and down to form a diverter device, the diverter plate is a convex structure, the convex top surface of the convex structure is arranged in contact with the bottom wall of the pressing plate, a plurality of powder channels are provided on the convex top surface of the convex structure, the plurality of powder channels are arranged in a divergent radial shape from the inlet side to the outlet side, a powder outlet communicating with the outlet side of the plurality of powder channels is formed between the pressing plate and the diverter plate located below the plurality of powder channels, a powder feeding port communicating with the inlet side of the plurality of powder channels is formed between the pressing plate and the diverter plate located above the plurality of powder channels, and the flat-mouthed outlet section is inserted into the powder feeding port and fixedly connected; The adjusting stud (6-4) of each powder cluster diverter is inserted into the corresponding fine-tuning support conduit (4) and is threadedly connected to the support lock nut on the fine-tuning support conduit. The bending section of each powder cluster diverter is inserted into the corresponding positioning support conduit. The rotating shaft positioning seat (6-6) is clearance-matched with the positioning support conduit. The rotating shaft positioning seat and the positioning support conduit are fixedly connected by bolts passing through the threaded hole (3-1) and the positioning hole (6-7). The limiting plate can be arranged in contact with the inner wall of the powder feeding chamber. The central axis of the limiting plate coincides with the central axis of the positioning support conduit on the corresponding side, and the powder outlet of each powder cluster diverter is connected to the bottom outlet of the powder feeding chamber. A cooling water device (7) is fixed in an annular sleeve on the outer wall of the lower part of the powder feeding chamber. The protective gas device (8) is arranged at the bottom outlet of the powder feeding chamber and is fixedly connected to the cooling water device by bolts. The protective gas device includes an annular air cavity (8-1), the middle hole of the annular air cavity is coaxially arranged with the bottom outlet of the powder feeding chamber, and the annular air cavity is connected to the air inlet pipe (8-2).

2. The laser broadband cladding powder feeding head according to claim 1, characterized in that: The outer diameter of the annular air cavity is more than 1.5 times larger than the long side of the laser beam.

3. The laser broadband cladding powder feeding head according to claim 1 or 2, characterized in that: The diameter of the air inlet pipe is greater than 6 mm, and a plurality of air outlet holes are opened on the bottom wall of the annular air cavity, and the diameter of the air outlet holes is not greater than 1.5 mm.

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