Self-cleaning laser processing equipment

Abstract

The invention discloses self-cleaning laser processing equipment which comprises a laser processing head, the laser processing head comprises a shell and a laser channel, a focus lens assembly and a protective lens assembly are arranged in the shell, the protective lens assembly is arranged below a focus lens, and the self-cleaning laser processing equipment further comprises a protective assembly for protecting the mirror surface of the protective lens assembly. The protection assembly comprises an air blowing channel, the air blowing channel introduces air into the space below the protection glass assembly, and the air flows to the laser outlet along the laser channel. According to the laser machining head, the air blowing channel is formed below the protective glass assembly of the laser machining head, air is introduced during machining, airflow is formed below the protective glass assembly so that dust can not be attached easily, airflow flowing downwards is formed, the airflow moving downwards is blown out from the laser outlet, dust can be reduced and prevented from moving upwards, and machining efficiency is improved. The heat dissipation effect can be achieved, abnormal refraction and reflection caused by heating deformation of the laser machining head are avoided, impurities generated by laser cleaning are blown away, or the heat dissipation effect can be used as protective gas to prevent plates from being oxidized during welding and cutting.

Description

Technical Field

[0001] The invention relates to self-cleaning laser processing equipment. Background Art

[0002] Laser processing is widely used in the manufacturing industry. Traditional laser processing mainly includes laser cleaning, laser welding and laser cutting. In the existing multifunctional or multi-purpose laser processing equipment, the above three laser processing methods are combined. The implementation method mainly includes: when using different processing methods, the three processing methods are switched by replacing the corresponding processing head, or by adjusting the laser generator and changing the parameters of the laser to achieve different processing methods. For example, a handheld laser cleaning, welding and cutting integrated device and method thereof are disclosed in the Chinese patent with publication number CN113560727A. The main structure of the laser processing head is very similar, mainly including a reflective device for changing the laser incident angle, a condenser device for focusing and a protective mirror device. In principle, laser cleaning is that the energy of the laser is quickly absorbed by impurities, a violent reaction is generated to vaporize the impurities, and the parameters of the laser are such that the substrate is not burned; laser welding is that the laser energy is quickly absorbed and melted by the substrate to achieve welding, and laser cutting is that the laser energy is absorbed and vaporized by the plate to achieve cutting. Generally speaking, the laser energy required for laser cleaning, laser welding and laser cutting is gradually increased. During the processing, the energy carried by the laser is absorbed in a very short time, and the reaction is violent. Sparks, smoke, etc. can be observed macroscopically. The movement trajectory of the dust generated by this violent energy absorption can be considered irregular and random. These impurities will enter the interior of the laser processing head along the laser channel, and part of them will be adsorbed on the lens, thereby affecting the light transmission rate or transmittance of the lens. The lens absorbs too much heat from the processed laser, which may even affect the quality of laser processing.

[0003] With the development of technology, lasers are also being further applied to more fields, such as laser additive manufacturing, which is a 3D printing technology that uses lasers as heat sources to perform cyclic and layer-by-layer rapid prototyping of metal parts. In the manufacturing process of metal parts, the matching of material addition and heat input is very strict. When the matching deviation between the laser heat input and the material addition occurs, cracks or defects may occur in the manufactured parts. Therefore, in this latest laser application field, the requirements for laser heat input are much more stringent than traditional laser processing methods, which also requires strict control of the deviation of energy loss during the laser input process. Summary of the invention

[0004] In view of the above shortcomings, the purpose of the present invention is to provide a self-cleaning laser processing equipment. By arranging an air blowing channel under the protective mirror assembly of the laser processing head, gas is introduced through the air blowing channel during processing to form an air flow under the protective mirror assembly so that dust is not easily attached, and a downward-flowing air flow is formed in the space below the protective mirror assembly to prevent dust from moving upward.

[0005] The traditional laser processing head is set in an elongated shape to prevent impurities and vaporized substances from splashing during laser processing from entering the laser channel easily. However, since the location where the violent reaction occurs during laser processing is generally opposite to the laser channel, some particles with a very small air equivalent diameter will inevitably enter the laser channel. In addition, due to the ionization effect generated during laser processing, the particles are charged and easily attached, and then inevitably act on the surface of the protective mirror.

[0006] To this end, the present invention provides a self-cleaning laser processing equipment, including a laser processing head, the laser processing head including a shell and a laser channel, a focusing mirror assembly and a protective mirror assembly are arranged inside the shell, the protective mirror assembly is arranged below the focusing mirror, and also includes a protective assembly for the mirror surface of the protective mirror assembly, the protective assembly includes an air blowing channel, the air blowing channel introduces gas into the space below the protective mirror assembly, and the gas flows along the laser channel to the laser outlet.

[0007] Furthermore, it also includes a box, a processing table, a robotic arm and a control panel, wherein the processing table is arranged on the upper surface of the box, the processing table is provided with a robotic arm, the laser processing head is connected to the robotic arm, and the control panel is used to select and set the laser processing mode and parameters, and the laser processing mode includes laser cutting, laser welding, laser cleaning and laser additive manufacturing.

[0008] Furthermore, the air blowing channel is arranged obliquely so that the gas is blown toward the mirror surface of the protective mirror assembly.

[0009] Furthermore, a connector is provided on the shell, the connector is hollow and connected to the air blowing channel, the connector is used to connect to the air pipe, the air pipe is fixed on the bracket, and the bracket is connected to the shell of the laser processing head; it also includes a nozzle, the nozzle is connected to the air pipe, and the nozzle is used to spray air toward the laser processing position.

[0010] Furthermore, a three-way valve is provided on the air pipe, and the three-way valve is connected to two inlets, wherein one inlet is used for introducing air, and the other inlet is used for introducing protective gas.

[0011] Furthermore, it also includes a cleaning component, which includes a nozzle for spraying cleaning agent onto the surface of the protective mirror.

[0012] Furthermore, the cleaning component also includes an outer shell and a lifting tube, the outer shell is arranged on the outside of the lifting tube, the lifting tube is arranged on the outside of the nozzle, the outer shell, the lifting tube and the nozzle are arranged in concentric circles, and the nozzle cooperates with the circular laser outlet so that the nozzle extends into the interior of the laser processing head, the lifting tube cooperates with the outer shell of the laser processing head so that the laser processing head pushes the lifting tube down, a reset spring is arranged under the lifting tube, and the outer shell is fixed on the box.

[0013] Furthermore, it also includes a liquid inlet pipe, and the outer shell, the lifting tube and the nozzle are provided with through holes. The position of the through hole on the lifting tube makes the lifting tube, the outer shell and the nozzle aligned when the lifting tube is pressed down into place by the laser head.

[0014] Furthermore, a rotating tube is provided on the outside of the nozzle, a cleaning cloth is provided on the top of the rotating tube, and the cleaning cloth is positioned higher than the top of the nozzle.

[0015] Furthermore, the shape of the nozzle is an inverted T-shape, and an inverted T-shaped rotating tube is sleeved on the upper side tube of the nozzle, and an external thread is provided on the lower side tube of the nozzle, and the sleeve is provided with an internal thread and screwed together with the external thread on the lower side tube, and the sleeve is provided with an upper wing plate and cooperates with the lower wing plate of the rotating tube to form a limit, and teeth or gears are provided on the outer wall of the rotating tube, and the rotating tube is driven to rotate by a motor, and the lifting tube is provided with an installation window, and the gear is arranged in the installation window.

[0016] The beneficial technical effects of the present invention are: A self-cleaning laser processing equipment of the present invention is provided with an air blowing channel below the protective mirror assembly of the laser processing head. During processing, gas is introduced through the air blowing channel to form an airflow below the protective mirror assembly so that dust is not easy to adhere, and a downward-flowing airflow is formed in the space below the protective mirror assembly. The downward-moving airflow is blown out from the laser outlet to reduce the dust from moving upward. In addition, the airflow can also dissipate heat for the protective mirror assembly and the housing to avoid abnormal refraction and reflection caused by thermal deformation. The airflow ejected from the laser outlet can also blow away impurities generated by laser cleaning, or serve as a protective gas to prevent oxidation of the plate during welding and cutting. In the above manner, precise control of the laser input energy during the laser processing process can be achieved, thereby avoiding defects in components caused during the laser processing process, especially in laser additive manufacturing.

[0017] A specific embodiment of a self-cleaning laser processing device of the present invention achieves multi-purpose functions of laser cleaning, laser welding, laser cutting and laser additive manufacturing by adjusting laser parameters. In order to avoid deviations in laser input energy during long-term use, especially defects in the laser additive manufacturing process, the specific embodiment of the present invention also cleans the mirror surface of the laser by arranging a cleaning component on the processing table to accurately control the energy loss in the laser path. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 A schematic diagram of a specific embodiment for implementing the present invention; Figure 2 It is a partial cross-sectional schematic diagram of a laser head; Figure 3 This is a schematic diagram of the air pipe control valve; Figure 4 is a top view schematic diagram of a cleaning component; Figure 5 is a cross-sectional schematic diagram of cleaning component embodiment 1; Figure 6 is a cross-sectional schematic diagram of a cleaning component embodiment 2; Figure 7 Schematic diagram of the lifting tube in Example 2.

[0019] Explanation of the reference numerals: 1. housing; 2. processing table; 3. robotic arm; 4. laser processing head; 401. housing; 402. focusing lens assembly; 403. protective lens assembly; 404. air blowing channel; 405. laser channel; 406. connector; 407. bracket; 408. nozzle; 409. air valve; 410. laser outlet; 5. optical cable; 6. electronic display screen; 7. air pipe; 8. three-way valve; 9. inlet; 10. cleaning assembly; 101. nozzle; 102. housing; 103. lifting tube; 104. reset spring; 105. liquid inlet pipe; 106. through hole; 107. rotating tube; 108. cleaning cloth; 109. sleeve; 110. external thread; 111. upper wing plate; 112. lower wing plate; 113. gear; 114. micro motor; 115. installation window; 116. ring body. DETAILED DESCRIPTION

[0020] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the specific implementation mode, structure, characteristics and effects of the present invention are described in detail below in combination with the accompanying drawings and preferred embodiments.

[0021] Reference Figures 1 to 3As shown, a self-cleaning laser processing device of the present invention includes a laser processing head 4, the laser processing head 4 includes a housing 401 and a laser channel 405, a focusing mirror assembly 402 and a protective mirror assembly 403 are arranged inside the housing 401, the protective mirror assembly 403 is arranged below the focusing mirror assembly, and also includes a protective assembly for the mirror surface of the protective mirror assembly 403, the protective assembly includes an air blowing channel 404, the air blowing channel 404 introduces gas into the space below the protective mirror assembly 403, and flows along the laser channel 405 to the laser outlet 410. In a specific embodiment, refer to Figure 1 As shown, it also includes a box body 1, a processing table 2 is arranged on the upper surface of the box body 1, wheels are arranged at the bottom of the box body 1, a laser generator is arranged in the box body 1, and is connected to a laser processing head 4 through an optical cable 5, and the laser processing head 4 is connected to a mechanical arm 3, and the mechanical arm 3 is installed on the box body 1 and has multiple degrees of freedom and is controlled by a numerical control system. A bracket is also arranged on one side of the processing table, and a control panel is arranged on the bracket. The control panel can adopt a touch-type electronic display screen 6, and the control panel is connected to the control system through a cable. This embodiment realizes the switching of laser cutting, laser welding or laser cleaning functions by setting and selecting corresponding laser parameters. Refer to Figure 2 As shown, the laser processing head 4 includes a housing 401, a laser channel 405 inside the housing 401, a laser focusing mirror assembly and a protective mirror assembly 403 arranged on the laser channel 405, and may also include a reflector assembly. After the incident laser is adjusted at an incident angle by the reflector assembly, it enters the focusing mirror assembly 402, and the laser is focused at a predetermined focal position to form a light spot, which is used to process the workpiece. The protective mirror assembly 403 seals the upper part and has good light transmittance. The air blowing channel 404 is arranged below the mirror surface of the focusing mirror assembly 402, and the air blowing channel 404 is connected to the air pipe 7. During the processing, gas is introduced below the mirror surface of the protective mirror assembly 403 to prevent dust from moving to the mirror surface and adhering to the mirror surface. Compared with the mirror surface of the sealed focusing mirror assembly 402, the mirror surface of the protective mirror assembly 403 is directly exposed, so it is relatively susceptible to the harsh environment of laser processing. When dust adheres to its surface, it will affect the light transmittance of its mirror surface, the light flux will decrease, and a large amount of laser energy will be absorbed by the dust on the mirror surface of the protective mirror assembly 403, causing the laser processing head 4 to heat up seriously, causing the deformation of the protective mirror assembly 403 and the housing 401, affecting the beam focusing, and reducing the laser energy gathered on the workpiece, thereby affecting the processing quality of the workpiece. In this embodiment, by setting the above-mentioned air blowing channel 404, the dust adhesion and the influence caused by the adhesion are reduced, and the air blowing channel 404 also forms a downward airflow in the laser channel 405, which is also conducive to heat dissipation. The airflow blown out from the laser outlet can also blow away the impurities vaporized during laser cleaning from the surface of the workpiece, or introduce protective gas to prevent the molten pool from being oxidized during laser welding and laser additive manufacturing, and introduce protective gas to prevent the cutting part from being oxidized and blow away the vaporized substances during laser cutting.

[0022] In the above embodiment, referring to Figure 2 As shown, the air blowing channel 404 is arranged obliquely upward so that the gas blows toward the mirror surface of the protective mirror assembly 403. A connector 406 is arranged on the housing 401. The connector 406 is hollow and communicated with the air blowing channel 404. The connector 406 is connected to the air pipe 7. The air pipe 7 is fixed on the bracket 407. The bracket 407 is connected to the housing 401 of the laser processing head 4. It also includes a nozzle 408, which is connected to the air pipe 7. The nozzle 408 is used to spray air toward the laser processing position. The air blowing channel 404 and the nozzle 408 can be connected to the same air pipe 7 through a three-way pipe. A gas valve 409 is arranged above the nozzle 408 for separate control. The air blowing channel 404 and the nozzle 408 can also be provided with independent air pipes. During laser cleaning, the laser spot will not burn the surface of the substrate, and air can be blown in to save the use cost. However, when laser welding and laser cutting are performed, high temperature easily causes oxidation of the processed material, and generally a protective gas needs to be introduced. A three-way valve 8 may be provided on the air pipe 7, and the three-way valve 8 is connected to two inlets 9, wherein the three-way valve 8 is used to allow one inlet 9 to be introduced into the air and communicated with the air pipe 7 or the other inlet 9 to be introduced into the shielding gas and communicated with the air pipe 7, and corresponding gases (such as air or shielding gas) may be introduced in different processing modes. The bracket 407 may also be provided with a card slot, which is used to clamp and fix the wire feeding mechanism of the welding wire when laser welding is adopted.

[0023] In the above embodiment, referring to Figures 4 to 7 As shown, it also includes a cleaning component 10, which is buried in the processing table 2, and the upper surface of the cleaning component 10 is flush with the processing table. Figure 4 and Figure 5The figure shows embodiment 1 of the cleaning component 10, wherein the cleaning component 10 comprises a concentric cylindrical nozzle 101, an outer shell 102 and a lifting tube 103, wherein the outer shell 102 is arranged on the outside of the lifting tube 103, and the lifting tube 103 is arranged on the outside of the nozzle 101, and the nozzle 101 cooperates with the circular laser outlet 410 so that the nozzle 101 extends into the interior of the laser processing head 4, and the lifting tube 103 cooperates with the outer shell 401 of the laser processing head 4 so that the laser processing head 4 pushes the lifting tube 103 down, and a reset spring 104 is arranged under the lifting tube 103, and the outer shell 102 is fixed on the box 1 or the processing table 2. When the transmittance of the protective mirror assembly 403 of the laser processing head 4 decreases or at a certain time interval, the laser processing head 4 is cleaned using a cleaning program. The cleaning program is selected through the control panel, and the control system controls the laser processing head 4 to move to the top of the cleaning assembly 10. The laser processing head 4 moves vertically downward and contacts the lifting tube 103. Under the downward squeezing action of the laser processing head 4, the spring at the bottom of the lifting tube 103 is deformed to make the lifting tube 103 descend. The nozzle 101 extends into the laser outlet. The nozzle 101 is started to spray liquid or water containing cleaning liquid to rinse the mirror surface of the protective mirror assembly 403. A drainage hole can be set at the corresponding position of the outer shell 102 to drain the water flowing out of the laser outlet of the laser processing head 4. Another part of the water can flow from the air blowing channel 404 to the nozzle, and the water is discharged through the control valve that controls the nozzle. The above-mentioned air pipe 7 can also be connected to a heating device for blowing hot air into the laser channel 405 through the air blowing channel 404 after cleaning is completed, and drying is fast. The heating device realizes hot air as a prior art, which will not be repeated here. In addition, since the laser additive manufacturing process involves complex cross-scale multi-physical fields, the performance of the solidified parts is highly sensitive to many factors. Monitoring sensors and their intelligent monitoring systems can also be set up to monitor local defects in the laser additive manufacturing process, so as to timely discover and predict local defects through changes in various parameters in the molten pool and its manufacturing process, and deal with them in a timely manner.

[0024] In the above embodiment 1, referring to Figure 5 As shown, it also includes a liquid inlet pipe 105, and a through hole 106 is provided on the outer shell 102, the lifting pipe 103 and the nozzle 101. The position of the through hole 106 on the lifting pipe 103 is such that when the lifting pipe 103 is pressed down into place by the laser head, the lifting pipe 103, the outer shell 102 and the through holes 106 on the nozzle 101 are aligned to realize water inflow and water spraying of the nozzle 101. A waterproof sealing structure is provided between the lifting pipe 103, the outer shell 102 and the nozzle 101, such as a common rubber cushion layer, to prevent leakage.

[0025] Reference Figure 6 and Figure 7As shown, the embodiment 2 of the present invention is basically the same as the embodiment 1, except that the embodiment 2 further includes a rotating tube 107 provided outside the nozzle 101, a cleaning cloth 108 provided on the top of the rotating tube 107, the cleaning cloth 108 is located higher than the top of the nozzle 101, and is used to wipe the mirror surface of the protective mirror assembly 403, and the cleaning assembly 10 can be provided with a cover to prevent dust, and the cover is opened when cleaning. After cleaning, the clean cleaning cloth 108 is immediately replaced. Specifically, the shape of the nozzle 101 is an inverted T-shape, and an inverted T-shaped rotating tube 107 is sleeved on the upper side tube of the nozzle 101, and an external thread 110 is provided on the lower side tube of the nozzle 101. The sleeve 109 is provided with an internal thread and is screwed together with the external thread 110 on the lower side tube. The sleeve 109 is provided with an upper wing plate 111 and cooperates with the lower wing plate 112 of the rotating tube 107 to form a limit. The outer wall of the rotating tube 107 is provided with teeth or gears 113, and the rotating tube 107 is driven by a motor to rotate through an engaged gear set. The lifting tube 103 is provided with an installation window 115, and the gear 113 is arranged in the installation window 115. The top and bottom of the lifting tube 103 are provided with a ring body 116, and a waterproof sealing structure is provided between the ring body 116 and the outer shell 102 and the rotating tube 107 for waterproofing. The above-mentioned gear 113 group and rotating tube 107 can be made of plastic material to avoid rust, and the motor can be a micro motor 114. In Example 2, the laser processing head can also be adaptively adjusted, such as changing the conical slender structure of the laser channel in the laser processing head to a cylindrical structure. Since dust prevention is no longer achieved through a slender structure, the length of the laser processing head can be appropriately shortened.

[0026] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Although the present invention has been disclosed as a preferred embodiment as above, it is not used to limit the present invention. Any technical personnel in this field can make some changes or modify the technical contents disclosed above into equivalent embodiments without departing from the scope of the technical solution of the present invention. However, any brief modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A self-cleaning laser processing device, comprising a laser processing head, the laser processing head comprising a housing and a laser channel, a focusing lens assembly and a protective lens assembly being arranged inside the housing, the protective lens assembly being arranged below the focusing lens, characterized in that: It also includes a protective component for the mirror surface of the protective mirror component, and the protective component includes an air blowing channel. The air blowing channel introduces gas into the space below the protective mirror component and flows along the laser channel to the laser outlet.

2. A self-cleaning laser processing equipment according to claim 1, characterized in that: It also includes a box, a processing table, a robotic arm and a control panel. The processing table is arranged on the upper surface of the box, and a robotic arm is arranged on the processing table. The laser processing head is connected to the robotic arm. The control panel is used to select and set the mode and parameters of laser processing. The laser processing mode includes laser cutting, laser welding, laser cleaning and laser additive manufacturing.

3. A self-cleaning laser processing equipment according to claim 2, characterized in that: The air blowing channel is arranged obliquely so that the gas is blown toward the mirror surface of the protective mirror assembly.

4. A self-cleaning laser processing equipment according to claim 2, characterized in that: The shell is provided with a connector, which is hollow and connected to the air blowing channel. The connector is used to connect to the air pipe, and the air pipe is fixed on a bracket, and the bracket is connected to the shell of the laser processing head; it also includes a nozzle, which is connected to the air pipe and is used to spray air toward the laser processing position.

5. A self-cleaning laser processing equipment according to claim 4, characterized in that: A three-way valve is provided on the air pipe, and the three-way valve is connected to two inlets, wherein one inlet is used for introducing air, and the other inlet is used for introducing protective gas.

6. A self-cleaning laser processing device according to any one of claims 2 to 5, characterized in that: It also includes a cleaning component, which includes a spray head for spraying cleaning agents on the surface of the protective mirror.

7. A self-cleaning laser processing equipment according to claim 6, characterized in that: The cleaning assembly also includes an outer shell and a lifting tube. The outer shell is arranged on the outside of the lifting tube, and the lifting tube is arranged on the outside of the nozzle. The outer shell, the lifting tube and the nozzle are arranged in concentric circles, and the nozzle cooperates with the circular laser outlet so that the nozzle extends into the interior of the laser processing head. The lifting tube cooperates with the outer shell of the laser processing head so that the laser processing head pushes the lifting tube down. A reset spring is arranged under the lifting tube, and the outer shell is fixed on the box.

8. The self-cleaning laser processing equipment according to claim 7, characterized in that: It also includes a liquid inlet pipe. The outer shell, the lifting tube and the nozzle are provided with through holes. The position of the through holes on the lifting tube makes the lifting tube, the outer shell and the nozzle aligned when the lifting tube is pressed down into place by the laser head.

9. A self-cleaning laser processing equipment according to claim 8, characterized in that: A rotating tube is arranged outside the nozzle, a cleaning cloth is arranged on the top of the rotating tube, and the position of the cleaning cloth is higher than the top of the nozzle.

10. A self-cleaning laser processing equipment according to claim 9, characterized in that: The shape of the nozzle is an inverted T-shape, an inverted T-shaped rotating tube is sleeved on the upper side tube of the nozzle, an external thread is provided on the lower side tube of the nozzle, the sleeve is provided with an internal thread and is screwed together with the external thread on the lower side tube, the sleeve is provided with an upper wing plate and cooperates with the lower wing plate of the rotating tube to form a limit, teeth or gears are provided on the outer wall of the rotating tube, and the rotating tube is driven to rotate by a motor, the lifting tube is provided with an installation window, and the gear is arranged in the installation window.

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