Method for welding a heat radiator by using rotating laser beams

Abstract

The laser rotation welding method for radiators of the present invention includes preparation, preliminary fixing and welding steps. First, a laser welding device and a radiator to be welded are prepared. The radiator has a body with a slot and a cooling pipe inserted into the slot, so that the positioning part of the cooling pipe and the peripheral surface of the second slot of the slot form a welding joint. Then, the laser unit of the laser welding device is driven to rotate around the radiator and weld within a 5 mm periphery of the welding joint at a welding angle between 0 and 30 degrees. Then, through self-melting, the molten liquid fills the gap of the welding joint, which not only improves the sealing effect after welding and effectively prevents leakage, but also prevents the equipment wiring from tangling and improves processing efficiency.

Description

Technical Field

[0001] This invention relates to a welding method, and more particularly to a laser rotary welding method for a radiator. Prior Technology

[0002] Currently, common laser welding equipment typically places the object to be welded on a rotating processing platform. The platform rotates the object synchronously, allowing the laser unit of the welding device to emit laser light along the joint of the object while remaining stationary, thus performing the welding. However, in actual use, it has been found that welding with only a single laser unit not only easily leads to poor processing efficiency, but also, if the object is heavy, the rotation speed of the processing platform is more likely to be slow. This results in the joint of the object being exposed to the laser light for too long, which can not only reduce the welding quality and effect, but may also affect the welding strength or damage the object. Furthermore, during the circumferential displacement process, the laser unit may become entangled with the wiring of other equipment, making it very inconvenient to use.

[0003] Further investigation revealed that current welding operations for radiators primarily utilize soft soldering. Referring to Figures 1 and 2, the radiator 1 comprises a body 11 and a plurality of cooling pipes 12 inserted into the body 11. The body 11 has a plurality of openings 111, a channel 112 communicating with the openings 111, and a plurality of internal threads 113 formed within the openings 111. Each cooling pipe 12 has a joint 121, and a connecting portion 121... The positioning part 122 of the connection 21 and a plurality of external threads 123 formed on the joint 121 are inserted into the opening 111 through the joint 121 of the cooling pipe 12, and the external threads 123 and the internal threads 113 are screwed together, so that the positioning part 122 of the cooling pipe 12 is in close contact with the surface of the body 11 to form a contact point. Then, solder is applied to cover the contact point and heated so that the solder melts and fills the contact point.

[0004] However, since the material of the solder is different from that of the heat sink 1 itself, the solder is prone to generating a potential difference with the cooling pipe 12 and the main body 11 after welding. In addition to causing the solder to rust easily during use, resulting in leakage, the solder cannot effectively seal the gap at the joint. Furthermore, the solder may generate pores during the welding process, causing gaps at the joint, resulting in poor anti-leakage and sealing effects. Therefore, when the heat sink 1 is used for heat dissipation on equipment, leakage may affect the use of the equipment or even damage the equipment, which needs to be improved. Summary of the Invention

[0005] Therefore, the purpose of this invention is to provide a laser rotary welding method for radiators, which can improve processing efficiency, effectively avoid tangling of equipment circuits, and achieve complete sealing by filling the weld with molten liquid through self-melting welding, thereby more effectively preventing leakage and extending service life.

[0006] Therefore, the laser rotational welding method for the radiator of the present invention includes preparation, preliminary fixing, and welding steps. In the preparation step, a laser welding device and a radiator to be welded are provided. The radiator has a body and a plurality of cooling pipes disposed on the body. The body has a channel and a plurality of slots communicating with the channel and for inserting the cooling pipes. Each slot has first and second slots communicating with each other, and a peripheral surface surrounded by the second slot. The maximum diameter of the first slot is smaller than the maximum diameter of the second slot, forming a placement surface between the first and second slots. Each cooling pipe has a joint and a positioning part. The laser welding device has a plurality of laser units that can move around a processing platform. In the preliminary fixing step, the cooling pipes are respectively installed on... The main body has slots to accommodate the joint in the first slot, and the positioning part is accommodated in the second slot and fits against the peripheral surface to form a weld. Then, in the welding step, the heat sink is placed on the processing platform, and the laser units move around the processing platform and irradiate the weld area within a 5mm radius at a welding angle between 0° and 30°. This allows the laser light from the laser units to completely irradiate the weld area with some overlapping irradiation areas, causing the heat sink to self-melt. The molten solution fills the gap in the weld area, thus completing the welding operation of the heat sink. This not only avoids the loss of the laser units entangled with other equipment circuits during their circumferential movement, but also improves the sealing effect after welding, ensures that leakage does not occur, and thus extends the service life and improves processing efficiency. Simple Explanation of the Diagram

[0007] Figure 1-2 is a schematic diagram of a conventional radiator. Figure 3 is a flowchart of the first preferred embodiment of the present invention. Figure 4-9 is a partial flowchart of the first preferred embodiment. Figure 10 is a flowchart of the second preferred embodiment of the present invention. Implementation

[0008] The foregoing description and other technical contents, features and effects of this invention will become clear in the following detailed description of the preferred embodiments with reference to the accompanying drawings.

[0009] Referring to Figures 3, 4, and 6, in a first preferred embodiment of the present invention, the laser rotation welding method for the heat sink 3 sequentially includes a preparation step, a preliminary fixing step, and a welding step. In the preparation step, a heat sink 3 to be welded, a laser welding device 4, and an air blowing device 5 are provided. The laser welding device 4 has a processing platform 41 and a plurality of laser units 42 that provide laser light irradiation, and the laser units 42 can move along the processing platform 41. 1. A circular displacement is performed. In this embodiment, the laser welding device 4 has three laser units 42, and each laser unit 42 moves around the outer periphery of the processing platform 41 by 125°. That is, the laser units 42 move in a circle around the processing platform 41, and the sum of the circumferential angles of the laser units 42 is greater than the circumferential angle 360°, so that the circumferential areas of the laser units 42 partially overlap, and the laser light irradiation areas of the laser units 42 also partially overlap.

[0010] Referring to Figures 3, 5, and 7, the air blowing device 5 has a blowing unit 51 for supplying gas and a cover 52 surrounding the processing platform 41. The blowing unit 51 can be moved around the processing platform 41. The gas is preferably an inert gas. The radiator 3 has a body 31 and at least one cooling pipe 32 inserted into the body 31. The following description uses an example where the body 31 has a plurality of cooling pipes 32. The body 31 also has at least one slot 311 and a channel 312 communicating with the slot 311. The following description uses an example where the body 31 has a plurality of slots 311 formed on it. The number of slots 311 corresponds to the number of cooling pipes 32. Each slot 311 has a first slot 3111 connected to the channel 312, a second slot 3112 connected to the first slot 3111 and communicating with the outside, a peripheral surface 3113 surrounded by the second slot 3112, and a plurality of internal threads 3114 formed on the inner wall surface of the first slot 3111. The maximum diameter 3111D of the first slot 3111 is smaller than the maximum diameter 3112D of the second slot 3112, so as to form a placement surface 3115 between the second slot 3112 and the first slot 3111. Each cooling pipe 32 has a joint 321, a positioning part 322 connected to the joint 321, and a plurality of external threads 323 spirally arranged on the surface of the joint 321.

[0011] Referring to Figures 3, 5, and 7, in this preliminary fixing step, each cooling pipe 32 is screwed and fixed to the body 31. First, the cooling pipe 32 is positioned and inserted into the corresponding slot 311, so that the joint 321 is accommodated in the first slot 3111. The external threads 323 and the internal threads 3114 engage with each other, so that the joint 321 is gradually screwed into the first slot 3111 until the positioning part 322 abuts against the placement surface 3115 and is limited. At the same time, the periphery of the positioning part 322 and the peripheral surface 3113 are tightly fitted to form a weld point P. Thus, the preliminary assembly of the cooling pipes 32 is completed.

[0012] Referring to Figures 3, 5, 6, and 8, in this welding step, the heat sink 3 is positioned on the processing platform 41 and surrounded by the cover 52. Then, the blowing unit 51 of the blowing device 5 is driven to blow gas toward the welding point P of the heat sink 3. The gas reduces the amount of oxygen in the welding process, thereby reducing the oxidation probability of the heat sink 3. Referring to Figure 9, the blowing unit 51 is preferably arranged with a C-shaped air outlet so that the gas blown by the blowing unit 51 can surround the welding point P without interfering with the laser irradiation.

[0013] Continuing from the previous description, the laser units 42 are then driven to perform circular motion, simultaneously irradiating a range of 5mm around the weld point P of the heat sink 3 with laser light. Since each laser unit 42 only circumvents and welds a portion of the weld point P, and the welding areas of any two laser units 42 partially overlap, the weld point P is fully irradiated and welded by the laser light. In addition, the laser light and the reference line P1 formed by the weld point P generate a welding angle θ, which is between 0∘ and 30∘, preferably between 5∘ and 15∘. This allows the laser light to penetrate deep into the surface of the weld point P and heat it, causing the heat sink 3 to undergo self-melting. The molten liquid fills the gaps of the weld point P and solidifies into one piece after cooling, thus completing the welding operation of the heat sink 3.

[0014] Referring to Figures 3 to 9, the laser units 42 cooperate to ensure that their trajectory completely covers the weld point P, and the laser beam irradiation ranges of the laser units 42 partially overlap. This not only allows for welding of larger or heavier heat sinks 3 or other objects, but also prevents the laser units 42 from tangling with the wiring of other equipment during their trajectory, improving usability and processing efficiency. Furthermore, the laser beams of the laser units 42 form welding angles θ between 0° and 30° with the baseline P1 of the weld point P, and the positioning part 322 of the cooling pipe 32 is partially accommodated in the second slot 3112 of the slot 311 and fits against the peripheral surface 3113 to form the weld point P, significantly increasing the melting depth. This allows the heat sink 3 to cool and solidify more effectively. The better bonding strength significantly improves the welding strength, thereby effectively preventing the cooling pipes 32 from detaching from the body 31 and ensuring that the weld P between the cooling pipes 32 and the body 31 is completely sealed without leakage. It also prevents the radiator 3 from being damaged by leakage, thus extending its service life. In addition, the laser rotation welding method of this invention can also weld the cooling pipes 32 that are closely arranged on the body 31, effectively reducing the time and cost of a single processing. Furthermore, the laser light will not be excessively reflected, resulting in poor laser light absorption, allowing the laser light to weld more accurately and quickly. The weld P is flat, aesthetically pleasing, and completely sealed, thereby reducing subsequent processing procedures. Moreover, the entire process is automated, making it more suitable for mass production operations.

[0015] Referring to Figure 10, the second preferred embodiment of the present invention still includes the components described in the first embodiment, and its purpose and effects are the same as those in the first embodiment, which will not be repeated here. The special feature of this embodiment is that after the welding step, there is a passivation step, in which the welded radiator 3 (not shown in the figure) is chemically treated to form a passivation film with high stability and dense structure on the surface of the radiator 3. The aforementioned passivation film can not only effectively block oxygen and slow down the oxidation rate of the radiator 3, but also improve the rust and corrosion prevention effect and extend the service life. At the same time, it can also increase the gloss of the surface, and can also achieve an aesthetic decorative effect by forming passivation films of different colors.

[0016] In summary, the laser rotation welding method for the radiator of the present invention includes preparation, preliminary fixing, and welding steps. After the cooling pipe is installed on the main body, a weld joint is formed between the positioning part and the peripheral surface. The laser units rotate around the radiator as the center, and the total rotation angle of the laser units is greater than 360 degrees, so that the rotation areas of the laser units partially overlap. At the same time, laser light is irradiated within a 5 mm radius of the weld joint at a welding angle between 0 and 30 degrees, so that the weld joint is completely welded and self-melted. The molten liquid fills the gap of the weld joint, which not only improves the sealing effect after welding and prevents leakage, but also prevents the equipment circuits from tangling and greatly improves the processing efficiency.

[0017] However, the above description is only for illustrating preferred embodiments of the present invention and should not be construed as limiting the scope of the present invention. Any simple equivalent changes and modifications made in accordance with the scope of the patent application and the contents of the specification of the present invention should still fall within the scope of the patent of the present invention.

[0018] (customary knowledge) 1: Radiator 11:Ontology 12: Cooling Piping 111: Opening 112: Channel 113: Internal thread 121: Joint 122: Positioning Department 123: External thread (This invention) 3: Radiator 31:Ontology 32: Cooling pipes 311: Slot 312: Channel 321: Joint 322: Positioning Department 323: External thread 3111: First slot 3111D: Maximum diameter of the first slot 3112: Second slot 3112D: Maximum diameter of the second slot 3113: Peripheral Surface 3114: Internal thread 3115: Placement surface P: Welding joint P1: Baseline θ: Welding angle 4: Laser welding equipment 41: Processing Platform 42: Laser Unit 5: Air blowing device 51: Blowing Unit 52: Cover

Claims

1. A laser rotary welding method for a heat sink, comprising: a preparation step, wherein a laser welding apparatus and a heat sink to be welded are provided, wherein, The laser welding apparatus has a processing platform and a plurality of laser units that provide laser light output, and the laser units can move around the processing platform. The heat sink has a body and at least one cooling pipe inserted into the body. The body has at least one slot and a channel formed inside and communicating with the slot. The slot has a second slot that surrounds the periphery and a first slot that connects the second slot and the channel respectively. The maximum diameter of the first slot is smaller than the maximum diameter of the second slot, thereby forming a placement surface connecting the first slot and the second slot. The cooling pipe has a joint and a positioning part that connects to the joint. A preliminary fixing step involves inserting the cooling pipe into the slot, positioning the joint of the cooling pipe in the first slot, while the positioning part of the cooling pipe is positioned by the second slot, and the positioning part forms a weld with the peripheral surface to complete the preliminary fixing of the cooling pipe; and a welding step involves placing the heat sink on the processing platform and having the laser units surround the heat sink, while irradiating a range of 5 mm around the weld with laser light, and the laser light and the reference line formed by the weld creating a welding angle between 0 degrees and 30 degrees, so that the laser light penetrates the weld and produces a self-melting phenomenon, thereby filling the gap of the weld with the molten solution, and then solidifying into one piece after cooling and solidification to complete the welding operation of the heat sink.

2. The laser rotational welding method for the radiator according to claim 1, wherein, The total angle of these laser units around the processing platform is greater than 360 degrees.

3. The laser rotational welding method for the radiator according to claim 1, wherein, Following the welding step, there is a passivation step, which passesivates the heat sink to form a passivation film on its surface.

4. The laser rotational welding method for the radiator according to claim 1, wherein, The spiral ring at the joint of the cooling pipe is provided with a plurality of external threads, and the spiral ring in the first slot of the slot is provided with a plurality of internal threads that match the external threads.

5. The laser rotational welding method for the radiator according to claim 1, wherein, The preparation step also includes an air blowing device that blows gas toward the radiator placed on the processing platform.

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