Adjustable laser coaxial powder feeding nozzle

[0023] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments.

[0024] as attached figure 1 , figure 2 and image 3 As shown in the figure, the present invention is characterized in that the lower part of the coaxial powder feeding nozzle is composed of a nozzle water cooling jacket 1, a protective gas jacket 4, a powder cavity jacket 6 and a laser jacket 8, and the upper part of the coaxial powder feeding nozzle is composed of a centering adjustment base 11. It is composed of lifting inner and outer sleeves 12, 13, a water cooling jacket 16 of the protective mirror and two threaded clamps. The nozzle water cooling jacket 1 is welded with cooling water inlet and outlet pipes 3 on its cylindrical part. The nozzle water cooling jacket 1 and the protective gas jacket 4 form a water cooling chamber. In order to prevent the phenomenon of "short-circuit circulation" of cooling water in the water-cooling cavity, a water-dividing screw block 2 is arranged in the water-cooling cavity. The cooling water conducts convective heat exchange. The cooling water pipes 3 (inlet and outlet pipes) differ by 180°. The inlet of the water inlet channel and the outlet of the spiral outlet channel on the water dividing screw block 2 correspond to the water inlet pipe and the water outlet pipe respectively.

[0025] The protective air sleeve 4 and the powder chamber body sleeve 6 are connected by thread to form a protective air chamber, the thickness of the protective air chamber can be adjusted between 1 and 3 mm, and 4 to 6 air supply pipes 5 are evenly distributed on the protective air chamber. An annular groove 22 is formed on the conical surface of the protective gas jacket 4 at the outlet, and the annular groove 22 can promote the uniform distribution of the protective gas in the air cavity. The included angle between the protective gas cavity and the axis of the laser cavity is 20-45°. The powder cavity sleeve 6 and the laser sleeve 8 are connected by threads to form a powder cavity. The thickness of the powder cavity can be adjusted between 1 and 3 mm. It can be adjusted steplessly during adjustment, and can also be adjusted through a standard washer. There are 4 to 6 powder feeding pipes 7 evenly distributed on the powder cavity. The included angle between the powder cavity and the axis of the laser cavity is 15-30°. The axes of the powder feeding pipe 7 and the gas feeding pipe 5 are tangent to the powder cavity and the protective gas cavity respectively, which is conducive to the spraying of powder and protective gas from the nozzle. Uniform extraction of nozzles provides assurance.

[0026]The inner side of the end of the laser sleeve 8 adopts a stepped structure to form a laser channel, which reduces the difficulty of production and manufacturing from the production process. The upper part of the laser sleeve 8 adopts a flange structure. The flange plate and the adjustment base 11 constitute the main body of the centering adjustment mechanism. There are four adjustment screws 10 on the adjustment base 11 corresponding to the height of the flange. Adjust the center of the nozzle laser sleeve as the center, and lock it with the lock nut 9. This adjustment mechanism guarantees centering between the laser focus and the powder focus. The adjusting base 11 is connected to the inner lifting sleeve 12 through a threaded connection, and a deformed lead screw nut mechanism is formed between the lifting inner sleeve 12 , the lifting outer sleeve 13 , the lifting nut 14 and the pressing nut 15 . The lifting mechanism in the nozzle ensures the coincidence of the laser focus and the powder convergence point and the adjustment of the defocus amount. The specific structure is: open four evenly distributed grooves on the lifting outer sleeve 13, and correspondingly extend four short claws on the outer circumference of the top of the lifting inner sleeve 12, and the four short claws are in the four Movement in the groove, the outer diameter of the lift inner sleeve 12 and the inner diameter of the lift outer sleeve 12 are clearance fit, the outside of the lift outer sleeve 13 is threaded, the lift nut 14 and the compression nut 15 are screwed on the lift outer sleeve 13, the four short claws of the lifting inner sleeve 12 are located between the lifting nut 14 and the pressing nut 15.

[0027] Considering the absorption, processability, weldability and thermal conductivity of the material to the laser, the manufacturing material of the powder feeding nozzle of the present invention mainly uses red copper or brass (copper has a very high reflectivity to the laser, excellent thermal conductivity, and is easy to process and welding).