Positioning fixture for laser welding of automobile parts

Abstract

This application relates to the field of laser welding positioning fixture technology, specifically a positioning fixture for laser welding of automotive parts. It includes a mounting bracket, a positioning fixture assembly disposed on the outside of the mounting bracket, and a rotating mechanism. A fixed suction cup is disposed on the outside of the positioning fixture assembly. It also includes a protective mechanism disposed on the mounting bracket, comprising a guide seat, a second electric telescopic rod, a limiting component, a pressurizing component, a guide plate, and a safety component. The guide seat is connected to the output end of the second electric telescopic rod, and the guide seat is sleeved on the outside of the limiting component. This positioning fixture for laser welding of automotive parts, through the setting of the safety component and the limiting component, forms a double locking mechanism, achieving rigid mechanical locking and frictional damping limiting in the clamping and unloading states. This effectively prevents the rotating mechanism from accidentally rotating due to gravity, vibration, or misoperation, greatly improving operator safety and equipment reliability.

Description

Technical Field

[0001] This application relates to the field of laser welding positioning fixture technology, and in particular to a positioning fixture for laser welding of automotive parts. Background Technology

[0002] Laser welding technology is increasingly widely used in the automotive parts manufacturing industry due to its advantages such as high energy density, narrow heat-affected zone, and small welding deformation. As a key component in laser welding systems, the positioning fixture directly determines the quality of the weld and the level of production efficiency.

[0003] For example, the patent document with publication number CN222552487U discloses a new type of laser welding fixture, which uses a cylinder to drive a rack and pinion gear in conjunction with a connecting rod to clamp the workpiece, and relies on a motor to drive the entire fixture to rotate to complete the workpiece flipping welding.

[0004] However, the application also has the following defects: the rotating parts generally lack effective safety locking mechanisms in the clamping and standby states. If the equipment is accidentally started when the operator clamps the workpiece, the rotating parts will directly drive the workpiece to rotate, which poses a serious personal safety hazard. At the same time, there is a lack of damping and suppression means for vibration and position drift during the rotation process. Therefore, a positioning fixture for laser welding of automotive parts is proposed to solve the above problems. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this application provides a positioning fixture for laser welding of automotive parts, which has advantages such as safety locking protection and solves the aforementioned problems.

[0006] This application provides a positioning fixture for laser welding of automotive parts, employing the following technical solution:

[0007] A positioning fixture for laser welding of automotive parts includes a mounting bracket, a positioning fixture assembly disposed on the outside of the mounting bracket, and a rotating mechanism. A fixing suction cup is disposed on the outside of the positioning fixture assembly.

[0008] It also includes a protective mechanism mounted on the mounting bracket. The protective mechanism includes a guide seat, an electric telescopic rod II, a limiting component, a pressurizing component, a guide plate, and a safety component. The guide seat is connected to the output end of the electric telescopic rod II. The guide seat is sleeved outside the limiting component. The electric telescopic rod II drives the guide seat to move, which in turn drives the limiting component to protect the rotating mechanism. At the same time, the guide seat is also connected to the safety component. When the guide seat moves, it will also release the safety lock of the safety component on the rotating mechanism.

[0009] The pressurizing components are respectively disposed inside the guide seat and on the mounting bracket, and the guide plate is mounted on the outside of the positioning fixture assembly. When the guide seat moves, the pressurizing components will also contact the guide plate. The outer side of the guide plate is provided with a ring-shaped and wave-shaped guide surface. When the rotating mechanism releases the safety lock, the rotating mechanism drives the positioning fixture assembly to rotate. At this time, the guide plate drives the pressurizing components to perform pressurization.

[0010] Optionally: the guide seat is provided through the middle, and the limiting component includes a plurality of elastic blocks, wherein the plurality of elastic blocks are distributed equidistantly in a ring and fixed to the outside of the mounting bracket, and the guide seat is sleeved on the outside of the plurality of elastic blocks.

[0011] Optionally: a limiting block is embedded in the inner side of each of the elastic blocks, and an interference fit pushing inclined surface is provided between the outer side of the elastic blocks and the inner side of the guide seat; when the guide seat is displaced by the drive of the electric telescopic rod II, the pushing inclined surface on the inner side of the guide seat and the pushing inclined surface on the outer side of the elastic block are interference fit, so that the multiple elastic blocks are centered together, thereby limiting the rotation mechanism.

[0012] Optionally: The pressurization assembly includes a pressurization piston, a connecting pipe and a nozzle. The guide seat has a chamber for sliding and sealing with the pressurization piston. The connecting pipe is installed on the outside of the mounting bracket. The nozzle is inclined and fixedly connected to the outside of the connecting pipe. An air supply pipe is fixedly connected between the chamber and the connecting pipe.

[0013] Optionally: one end of the booster piston extends to the outside of the guide seat, wherein the end of the booster piston is provided with an arc-shaped abutment that abuts against the guide surface, and a return spring connected to the inner wall of the cavity is wound around the outside of the booster piston.

[0014] Optionally: The safety component is located on the side of the mounting bracket away from the limiting component. The safety component includes a positioning ring, a positioning rod, and a connecting rod. The positioning ring is bolted to the outside of the mounting bracket. The connecting rod slides through the inside of the mounting bracket, and one end of the connecting rod is fixed to the outside of the guide seat. The positioning rod slides through the inside of the positioning ring and connects to the rotating mechanism to achieve a safety limit on the rotating mechanism.

[0015] Optionally: The top end of the positioning rod is threaded with a concave frame that is connected to the other end of the connecting rod. A guide shaft is rotatably mounted on the inner side of the concave frame. The guide shaft passes through the interior of the connecting rod, and the interior of the connecting rod has an oblique guide groove that rolls with the guide shaft.

[0016] Optionally, the positioning clamp assembly includes a hollow mounting shell, two clamps disposed on the outside of the mounting shell, a rotating shaft rotatably mounted in the middle of the interior of the mounting shell, a transmission gear fixed to one end of the rotating shaft, an electric telescopic rod fixed inside the mounting shell, and a toothed plate fixed to the output end of the electric telescopic rod and meshing with the transmission gear.

[0017] Optionally: The other end of the rotating shaft is provided with a connector that is connected to the two clamps. The connector includes a swing arm fixed to the end of the rotating shaft. The two sides of the swing arm and the two clamps are hinged with connecting rods. The outer sides of the two clamps are each equipped with a slide block that is slidably connected to the mounting shell.

[0018] Optionally: The rotating mechanism includes a rotating shaft and a servo motor. The rotating shaft bearing is installed inside the mounting bracket. One end of the rotating shaft is fixed to the outer wall of the mounting housing. The other end of the rotating shaft is provided with a meshing transmission gear between it and the output shaft of the servo motor.

[0019] In summary, this application includes at least one of the following beneficial technical effects:

[0020] 1. This invention establishes a dual locking mechanism by setting up a safety component and a limiting component. It achieves rigid mechanical locking and friction damping limiting in the clamping and unloading states, effectively preventing the rotating mechanism from rotating accidentally due to gravity, vibration or misoperation, and greatly improving the safety of operators and the reliability of equipment.

[0021] 2. This invention employs a dual positioning method of fixed suction cup vacuum pre-adsorption and mechanical secondary clamping of fixtures. This method can adapt to the clamping requirements of various automotive parts, such as flat surfaces, curved surfaces, irregular shapes, and thin walls, avoiding deformation caused by rigid clamping. It can also solve the problems of workpiece offset, shaking, and loosening during welding. Combined with the gear connecting rod adaptive opening and closing structure, it can accurately adapt to workpieces of different specifications and sizes, with high positioning accuracy and strong versatility, effectively reducing the welding defect rate.

[0022] 3. This invention utilizes the rotational motion during welding to drive the wave-shaped guide surface to generate airflow through the pressurized piston. The airflow can promptly remove welding slag, fumes, and metal debris generated during laser welding, preventing impurities from adhering and affecting the formation of the molten pool. At the same time, it can rapidly cool the high-temperature welding area to prevent thermal deformation and ablation of components, and reduce the corrosive pollution of precision optical lenses and equipment caused by fumes. Attached Figure Description

[0023] Figure 1 This is a three-dimensional view of the overall structure of this application;

[0024] Figure 2 This is a cross-sectional view of the positioning fixture assembly of this application;

[0025] Figure 3 This is a three-dimensional structural view of the positioning fixture assembly of this application;

[0026] Figure 4 This is a three-dimensional structural diagram of the organization protected by this application;

[0027] Figure 5 This is a structural side view of the organization protected by this application;

[0028] Figure 6 This is a cross-sectional view of the structure of the organization protected by this application;

[0029] Figure 7 This application Figure 6 A magnified structural diagram of structure A is shown below;

[0030] Figure 8 This is a schematic diagram of the structure of the insurance component in this application.

[0031] Explanation of reference numerals in the attached figures:

[0032] 1. Mounting bracket; 2. Positioning clamp assembly; 21. Mounting housing; 22. Clamp; 23. Slide; 24. Rotating shaft; 25. Connecting piece; 251. Swing arm; 252. Connecting rod; 26. Transmission gear; 27. Electric telescopic rod one; 28. Gear plate; 3. Rotating mechanism; 31. Rotating shaft; 32. Servo motor; 33. Transmission gear; 4. Fixed suction cup; 5. Protection mechanism; 51. Guide seat; 52. Electric telescopic rod two; 53. Limiting assembly; 53 1. Elastic block; 532. Limiting block; 533. Pushing inclined surface; 54. Pressurizing component; 541. Pressurizing piston; 542. Connecting pipe; 543. Nozzle; 544. Chamber; 545. Abutment joint; 546. Return spring; 547. Air supply pipe; 55. Guide plate; 551. Guide surface; 56. Safety component; 561. Positioning ring; 562. Positioning rod; 563. Connecting rod; 564. Concave frame; 565. Guide shaft; 566. Angled guide groove. Detailed Implementation

[0033] The following is in conjunction with the appendix Figures 1-8 This application will be described in further detail.

[0034] like Figures 1-8 As shown, this embodiment provides a positioning fixture for laser welding of automotive parts, which mainly includes a mounting bracket 1 for supporting and fixing the entire device, a positioning fixture assembly 2 disposed on the outside of the mounting bracket 1 for performing workpiece clamping function, and a rotating mechanism 3 mounted on the mounting bracket 1 and connected to the positioning fixture assembly 2 for transmission.

[0035] To further improve the workpiece's resistance to vibration and loosening during the welding process, a fixed suction cup 4 is also provided on the outside of the positioning fixture assembly 2 to provide auxiliary negative pressure adsorption force. Specifically, the fixed suction cup 4 adopts a negative pressure vacuum flexible adsorption structure, which can be adapted to the pre-fixation operation of flat, curved, irregularly shaped structures and thin-walled automotive parts, to achieve flexible adsorption positioning without squeezing, avoiding problems such as workpiece indentation, deformation and damage caused by the hard clamping of traditional rigid fixtures. The fixed suction cup 4 is connected to the vacuum equipment.

[0036] The positioning fixture assembly 2 is the core workpiece clamping and positioning structure of this device, mainly used to position and firmly clamp automotive parts of different specifications. Specifically, it includes a hollow mounting shell 21, two clamps 22 symmetrically arranged on the outside of the mounting shell 21, a rotating shaft 24 rotatably mounted inside the mounting shell 21 at the middle position via bearings, a transmission gear 26 fixedly mounted at one end of the rotating shaft 24, an electric telescopic rod 27 fixedly mounted inside the mounting shell 21, and a toothed plate 28 fixedly connected to the output end of the electric telescopic rod 27 and meshing with the transmission gear 26. A sliding guide rail is provided between the back of the toothed plate 28 and the inner wall of the mounting shell 21 to ensure the straightness of the toothed plate 28's translation.

[0037] In the clamping action conversion stage, the other end of the rotating shaft 24 is provided with a connecting member 25 that is linked to the two clamps 22. The connecting member 25 includes a swing arm 251 that is radially fixed to the end of the rotating shaft 24. The two protruding ends of the swing arm 251 are connected to the inner extension arms of the two clamps 22 by connecting rods 252 through pins. In addition, the outer sides of the two clamps 22 are fixedly installed with slide blocks 23 that slide in cooperation with the slide rails on the outer side wall of the mounting housing 21, which are used to limit the clamps 22 to reciprocate in a straight line. When the electric telescopic rod 27 pushes the toothed plate 28 to move linearly, the toothed plate 28 drives the transmission gear 26 and the rotating shaft 24 to rotate. The swing arm 251 swings accordingly and pulls the two clamps 22 to move closer or further away from each other along the slide block 23 through the connecting rods 252, so as to achieve centered clamping.

[0038] The supporting rotating mechanism 3 is mainly used to drive the fixture assembly and clamp the workpiece to rotate precisely at multiple angles, meeting the needs of multi-directional continuous laser welding processing. It includes a rotating shaft 31 as the output shaft and a servo motor 32 that provides power. The rotating shaft 31 is rotatably mounted inside the central shaft hole of the mounting bracket 1 through two sets of preloaded angular contact ball bearings. The front journal of the rotating shaft 31 is fixedly connected to the outer wall of the mounting housing 21 through a flange or key connection to achieve torque transmission. A meshing transmission gear 33 is provided between the rear end of the rotating shaft 31 and the output shaft of the servo motor 32. This transmission gear 33 is preferably a reduction gear or a worm gear and worm, which is used to increase the output torque while reducing the rotational speed, ensuring that the positioning fixture assembly 2 can stably support the heavy automotive parts.

[0039] The positioning fixture in this embodiment also includes a protection mechanism 5 mounted on the mounting bracket 1. The protection mechanism 5 comprises a guide seat 51 for performing multi-stage linkage, an electric telescopic rod 52 as the active power source, a limiting component 53 for limiting the rotation shaft 31, a pressurizing component 54 for generating a follow-up high-pressure airflow, a guide disk 55 as a rotation trigger cam, and a safety component 56 for achieving mechanical hard locking. The guide seat 51 is directly fixedly connected to the output end of the electric telescopic rod 52, and is axially slidably fitted onto the outside of the limiting component 53. Specifically, the telescopic movement of the electric telescopic rod 52 causes the guide seat 51 to shift axially, thereby driving the limiting component 53 to perform damped engagement protection on the rotation mechanism 3. Simultaneously, since the guide seat 51 is also mechanically linked to the safety component 56, the guide seat 51 will also simultaneously release the rigid safety lock of the safety component 56 on the rotation mechanism 3 during displacement, achieving efficient coordinated control with one drive and two actions.

[0040] Regarding the pressurization function, some components of the pressurization assembly 54 are located inside the guide seat 51, while the remaining components are fixedly installed at corresponding positions on the mounting bracket 1. The guide plate 55 is coaxially fixedly installed on the outer wall of the positioning clamp assembly 2. When the guide seat 51 is driven by the electric telescopic rod 52 to move towards the positioning clamp assembly 2 to the predetermined end of the stroke, the movable end of the pressurization assembly 54 will form a contact engagement with the end face side wall of the guide plate 55. Specifically, the outer circumferential surface of the guide plate 55 is provided with a ring-shaped guide surface 551 that extends in a wavy pattern along the circumference. When the safety lock of the rotating mechanism 3 is completely released, the rotating mechanism 3 drives the positioning clamp assembly 2 and its outer guide plate 55 to rotate together. At this time, the wavy guide surface 551 on the guide plate 55 will continuously drive the pressurization assembly 54 to perform reciprocating pressurization work, thereby directly converting the mechanical energy of the rotational motion into the pressure energy of compressed air, without the need for an additional independent air pump.

[0041] To ensure uniformity of the limiting action and response speed, the guide seat 51 adopts a circular annular structure with a central through-hole. The limiting component 53 includes several arc-shaped elastic blocks 531 with elastic deformation capability. The elastic blocks 531 are distributed equidistantly in a ring along the circumference of the mounting bracket 1, and the root of each elastic block 531 is fixed to the outer surface of the mounting bracket 1 by screws or welding. The inner hole of the guide seat 51 is fitted onto the outer side of the annular body formed by the several elastic blocks 531.

[0042] Regarding the detailed reinforcement of the limiting structure, several elastic blocks 531 are each embedded with a high-hardness limiting block 532 with an anti-slip texture on its inner sidewall. This limiting block 532 is used to directly contact the outer wall of the rotating shaft 31, and the elastic block 531 is adapted to the rotating shaft 31. At the same time, a pushing inclined surface 533 is provided between the outer sidewall of the several elastic blocks 531 and the inner sidewall of the guide seat 51, which cooperates with each other and can form an interference fit. The inclination direction of the pushing inclined surface 533 is set so that when the guide seat 51 moves axially, it can force the elastic block 531 to produce a radially inward contraction displacement. When the guide seat 51 is axially displaced by the electric telescopic rod 52, the pushing inclined surface 533 on the inner side of the guide seat 51 and the pushing inclined surface 533 on the outer side of the elastic block 531 are pressed together by an interference fit. Under the action of the inclined surface pressing effect, multiple elastic blocks 531 are simultaneously hugged towards the center, thereby achieving uniform circumferential damping and limiting of the rotating shaft 31 of the rotating mechanism 3, effectively suppressing the vibration of the rotating shaft 31 during high-speed start-up and shutdown.

[0043] To achieve a stable and reliable compression effect, the booster assembly 54 specifically includes a booster piston 541 as a movable compression element, a connecting pipe 542 as a gas collection channel, and a nozzle 543 as a final injection actuator. The nozzle 543 is mounted on the outer wall of the mounting bracket 1. The guide seat 51 has a cylindrical chamber 544 radially or axially formed inside, which slides and seals with the booster piston 541. The inner wall of this chamber 544 is precision ground and fitted with a lubricating sealing ring. The connecting pipe 542 is fixedly mounted on the outer wall of the mounting bracket 1 using a pipe clamp. The nozzle 543 is fixedly connected to the outer wall of the connecting pipe 542 at a preset angle towards the welding area. A flexible gas supply pipe 547 is fixedly connected between the outlet of the chamber 544 and the inlet of the connecting pipe 542 to compensate for the relative movement generated when the guide seat 51 is displaced. It should be noted that the gas supply pipe 547 consists of a check valve and a pipe; a check valve can also be installed inside the chamber 544.

[0044] On the external contact structure of the piston, one end of the booster piston 541 extends from the reserved through hole of the guide seat 51 to the outside of the guide seat 51. The extended end of the booster piston 541 is fixedly provided with an abutment 545 having an arc shape and always elastically abutting against the guide surface 551. Furthermore, a return spring 546 is fitted on the outside of the booster piston 541. One end of the return spring 546 abuts against the inner wall of the chamber 544, and the other end abuts against the shoulder of the booster piston 541. This spring is used to push the booster piston 541 to automatically return to its original position at the trough of the guide disc 55, in preparation for the next compression stroke.

[0045] It is important to note that after the safety lock is released and the pre-limit engagement takes effect, the servo motor 32 starts operating according to the preset welding path. Through the transmission gear 33, it performs deceleration and torque amplification transmission, driving the rotating shaft 31 to rotate at a precisely controlled angular velocity. This, in turn, causes the entire positioning fixture assembly 2 and the automotive parts it holds to rotate at multiple angles. During this process, the laser welding equipment can coordinate with the rotational motion to complete continuous welding operations on the circumferential welds, spiral welds, or multi-segment spatial curve welds of the parts. The entire welding process requires no manual disassembly or adjustment of the parts' angles midway, significantly improving welding continuity and positional accuracy compared to traditional segmented welding methods.

[0046] Most importantly, as the positioning clamp assembly 2 rotates continuously, the guide plate 55, fixedly mounted on its outer side, rotates synchronously. The wave-shaped guide surface 551 on the outer ring of the guide plate 55 continuously and intermittently compresses the abutment 545 at the end of the pressure boosting piston 541. When the abutment 545 is at the crest of the wave, the guide surface 551 pushes the pressure boosting piston 541 to overcome the elastic force of the return spring 546 and slide it into the chamber 544, compressing the air inside the chamber 544 and generating instantaneous high pressure; when the abutment 545 slides to the trough of the wave, the return spring 546 pushes the pressure boosting piston 541 to return to its original position, preparing for the next compression. This reciprocating motion forms a stable pulsed high-pressure airflow.

[0047] The compressed high-pressure airflow is delivered through the gas supply pipe 547 to the connecting pipe 542 fixedly installed on the mounting bracket 1 for collection, and finally ejected at high speed by the inclined nozzle 543 pointing towards the welding molten pool area. This airflow has multiple beneficial effects: First, the high-pressure airflow can promptly blow away the welding slag, metal vapor condensate, and dust particles generated during laser welding, preventing these impurities from adhering to the welding surface of the parts or the edge of the molten pool, thereby effectively preventing the generation of welding defects such as porosity and slag inclusions, and significantly improving the weld formation quality; Second, the high-speed flowing cooling airflow can directly act on the high-temperature heat-affected zone of the weld, forcibly and rapidly cooling it, effectively preventing thin-walled parts from thermal deformation, ablation, or coarsening of the metallographic structure due to heat accumulation; Third, continuous airflow purging can draw a large amount of welding fumes away from the laser beam path and focusing lens, reducing the corrosion and pollution of the equipment's precision optical structure by the fumes, and extending the equipment maintenance cycle and service life.

[0048] To improve space utilization and ensure the reliability of the release mechanism, the safety assembly 56 is located on the side of the mounting bracket 1 away from the limiting assembly 53. The safety assembly 56 includes a positioning ring 561 fixed to the mounting bracket 1, a positioning rod 562 for inserting into the locking hole of the rotating shaft, and a connecting rod 563 for transmitting the displacement of the guide seat 51. The positioning ring 561 is fastened to the outer end face of the mounting bracket 1 with multiple bolts. The connecting rod 563 slides axially through a guide hole inside the mounting bracket 1, and one end of the connecting rod 563 is fixedly connected to the outer end face of the guide seat 51 by thread or welding. The positioning rod 562 slides axially through the guide hole inside the positioning ring 561, and its end is inserted into the locking hole on the end face of the rotating shaft 31 of the rotating mechanism 3, thereby achieving rigid safety limiting of the rotating mechanism 3.

[0049] Regarding the motion conversion structure, a concave frame 564 is threadedly installed at the top of the positioning rod 562, and the other end of the concave frame 564 is movably connected to the end of the connecting rod 563. A guide shaft 565 is rotatably mounted on the inner side of the concave frame 564 via a bearing. The guide shaft 565 passes through the oblong hole at the end of the connecting rod 563, and the connecting rod 563 has a slanted guide groove 566 that forms a rolling fit with the guide shaft 565. When the connecting rod 563 moves axially with the guide seat 51, the slanted guide groove 566 generates a lateral thrust on the guide shaft 565, forcing the concave frame 564 and the positioning rod 562 to rise or fall in a direction perpendicular to the axial direction, thereby releasing and restoring the safety lock. It should be noted that in this structure, the connecting rod 563 simultaneously undertakes a dual key function. First, as a power transmission component for unlocking the safety lock, when the guide seat 51 is axially displaced, the connecting rod 563 slides through it and drives the positioning rod 562 to rise and fall through the inclined guide groove 566 at its end, thereby realizing the release and restoration of the safety lock. At the same time, as an auxiliary limiting and guiding function of the guide seat 51, the outer wall of the connecting rod 563 and the inner wall of the guide through hole inside the mounting bracket 1 form a precision sliding fit pair. Since one end of the connecting rod 563 is rigidly fixed to the end face of the guide seat 51, when the guide seat 51 moves axially under the drive of the electric telescopic rod 52, the connecting rod 563 slides synchronously through it, applying additional axial constraints to the guide seat 51. This effectively prevents the guide seat 51 from eccentric tilting or circumferential deflection when subjected to the radial compression reaction force of the elastic block 531, ensuring that the pushing inclined surface 533 on the inner side of the guide seat 51 and the pushing inclined surface 533 on the outer side of the multiple elastic blocks 531 always maintain a precise concentric alignment, thereby ensuring the uniformity and synchronicity of the clamping action of the multiple sets of elastic blocks 531.

[0050] Meanwhile, the maximum axial sliding stroke of the connecting rod 563 is physically limited by the limiting step surface inside the guide through hole of the mounting bracket 1 or by the limiting shoulder provided on the connecting rod 563 body. This mechanical limiting structure can rigidly limit the extreme displacement position of the guide seat 51 when there is a deviation in the stroke control of the electric telescopic rod 52, effectively preventing the guide seat 51 from being damaged by over-travel impact, thus further improving the safety redundancy of the equipment.

[0051] Combined with appendix Figures 1-8 The working principle of the above embodiments is as follows:

[0052] In the initial state of operation, the safety component 56 is locked, and the positioning rod 562 is engaged with the rotating shaft 31 to restrict the rotation of the rotating mechanism 3 and prevent the equipment from moving accidentally during clamping. The worker places the automotive parts to be welded in the position of the clamp 22 and the fixed suction cup 4. First, the fixed suction cup 4 is used to adsorb and fix them. Then, the electric telescopic rod 27 is activated to extend and push the toothed plate 28 to move horizontally. Through gear meshing, the transmission gear 26 and the rotating shaft 24 are rotated, which drives the swing arm 251 to swing. Through the connecting rod 252, the two sets of clamps 22 are driven to move synchronously along the slide 23 to prevent the parts from shifting or shaking during welding.

[0053] When the workpiece needs to be rotated, the electric telescopic rod 52 is retracted, causing the guide seat 51 to move upward. During the displacement of the guide seat 51, the inner side and the outer side of the elastic block 531 are pressed together by the interference fit of the pushing inclined surface 533, which pushes multiple sets of elastic blocks 531 toward the center, so that the inner limit block 532 fits and hugs the rotating shaft 31, realizing the pre-limit of the rotating shaft 31 and improving the stability of the rotation operation. At the same time, the displacement of the guide seat 51 causes the connecting rod 563 to move synchronously. Through the rolling guidance of the inclined guide groove 566 inside the connecting rod 563 and the guide shaft 565, the concave frame 564 and the positioning rod 562 are driven to rise upward, so that the positioning rod 562 is disengaged from the locking groove of the rotating shaft 31, and the locking restriction of the safety component 56 on the rotating mechanism 3 is released, and the equipment enters the rotatable welding state.

[0054] After the safety lock is released, the servo motor 32 starts and drives the rotating shaft 31 to rotate precisely through the transmission gear 33, thereby driving the overall positioning fixture assembly 2 and the clamped automotive parts to rotate at multiple angles. In conjunction with the laser welding equipment, continuous welding operations are completed at different positions and angles of the parts. There is no need for manual disassembly and adjustment of the parts, and the welding continuity and accuracy are greatly improved.

[0055] During the rotation of the positioning fixture assembly 2, the outer guide plate 55 rotates synchronously. Its outer wavy guide surface 551 continuously and intermittently squeezes the abutment 545 of the pressure boosting piston 541, pushing the pressure boosting piston 541 to slide into the chamber 544, compressing the air inside the chamber 544. The compressed high-pressure airflow is then transported to the connecting pipe 542 through the air supply pipe 547, and finally ejected at high speed by the inclined nozzle 543. By blowing the welding operation area with high-speed airflow, on the one hand, welding slag, fumes, and metal debris generated by laser welding can be removed in time, preventing impurities from adhering to the welding surface of the parts and affecting the welding quality; on the other hand, the high-temperature welding area can be rapidly cooled by air cooling to prevent the parts from deforming or burning due to high temperature, while reducing the corrosion and pollution of the precision structure of the equipment by welding fumes.

[0056] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A positioning fixture for laser welding of automotive parts, comprising a mounting bracket (1), a positioning fixture assembly (2) disposed outside the mounting bracket (1), and a rotating mechanism (3), characterized in that: The positioning clamp assembly (2) is provided with a fixing suction cup (4) on its outer side. It also includes a protection mechanism (5) set on the mounting bracket (1). The protection mechanism (5) includes a guide seat (51), an electric telescopic rod two (52), a limiting component (53), a pressurizing component (54), a guide plate (55), and a safety component (56). The guide seat (51) is connected to the output end of the electric telescopic rod two (52). The guide seat (51) is sleeved on the outside of the limiting component (53). The electric telescopic rod two (52) drives the guide seat (51) to move and drive the limiting component (53) to protect the rotating mechanism (3). At the same time, the guide seat (51) is also connected to the safety component (56). When the guide seat (51) moves, it will also release the safety lock of the safety component (56) on the rotating mechanism (3). The pressurizing component (54) is respectively disposed inside the guide seat (51) and on the mounting bracket (1), and the guide plate (55) is installed on the outside of the positioning fixture assembly (2); when the guide seat (51) is displaced, the pressurizing component (54) will also contact the guide plate (55), and the outer side of the guide plate (55) is provided with a ring-shaped and wave-shaped guide surface (551); when the rotating mechanism (3) releases the safety lock, the rotating mechanism (3) drives the positioning fixture assembly (2) to rotate, and at this time the guide plate (55) drives the pressurizing component (54) to perform pressurizing work.

2. The positioning fixture for laser welding of automotive parts according to claim 1, characterized in that: The guide seat (51) is provided through the middle, and the limiting component (53) includes a number of elastic blocks (531). The number of elastic blocks (531) are distributed in a ring at equal intervals and fixed on the outside of the mounting bracket (1). The guide seat (51) is sleeved on the outside of the number of elastic blocks (531).

3. A positioning fixture for laser welding of automotive parts according to claim 2, characterized in that: Each of the elastic blocks (531) has a limiting block (532) embedded on its inner side. An interference fit push slope (533) is provided between the outer side of the elastic blocks (531) and the inner side of the guide seat (51). When the guide seat (51) is displaced by the electric telescopic rod (52), the push slope (533) on the inner side of the guide seat (51) and the push slope (533) on the outer side of the elastic block (531) are interference fit, so that the multiple elastic blocks (531) are centered together, thereby limiting the rotation mechanism (3).

4. The positioning fixture for laser welding of automotive parts according to claim 1, characterized in that: The pressurization assembly (54) includes a pressurization piston (541), a connecting pipe (542), and a nozzle (543). The guide seat (51) has a chamber (544) inside which is used for sliding and sealing with the pressurization piston (541). The connecting pipe (542) is installed on the outside of the mounting bracket (1). The nozzle (543) is inclined and fixedly connected to the outside of the connecting pipe (542). A gas supply pipe (547) is fixedly connected between the chamber (544) and the connecting pipe (542).

5. A positioning fixture for laser welding of automotive parts according to claim 4, characterized in that: One end of the booster piston (541) extends to the outside of the guide seat (51), wherein the end of the booster piston (541) is provided with an arc-shaped abutment (545) that abuts against the guide surface (551), and a return spring (546) connected to the inner wall of the chamber (544) is wound around the outside of the booster piston (541).

6. A positioning fixture for laser welding of automotive parts according to claim 1, characterized in that: The safety component (56) is located on the side of the mounting bracket (1) away from the limiting component (53). The safety component (56) includes a positioning ring (561), a positioning rod (562), and a connecting rod (563). The positioning ring (561) is bolted to the outside of the mounting bracket (1). The connecting rod (563) slides through the inside of the mounting bracket (1), and one end of the connecting rod (563) is fixed to the outside of the guide seat (51). The positioning rod (562) slides through the inside of the positioning ring (561) and is connected to the rotating mechanism (3) to achieve safety limiting of the rotating mechanism (3).

7. A positioning fixture for laser welding of automotive parts according to claim 6, characterized in that: The top end of the positioning rod (562) is threaded with a concave frame (564) that is connected to the other end of the connecting rod (563). A guide shaft (565) is rotatably mounted on the inner side of the concave frame (564). The guide shaft (565) passes through the interior of the connecting rod (563). The interior of the connecting rod (563) is provided with an oblique guide groove (566) that rolls with the guide shaft (565).

8. A positioning fixture for laser welding of automotive parts according to claim 1, characterized in that: The positioning clamp assembly (2) includes a hollow mounting shell (21), two clamps (22) disposed on the outside of the mounting shell (21), a rotating shaft (24) rotatably mounted in the middle of the interior of the mounting shell (21), a transmission gear (26) fixed to one end of the rotating shaft (24), an electric telescopic rod (27) fixed inside the mounting shell (21), and a toothed plate (28) fixed to the output end of the electric telescopic rod (27) and meshing with the transmission gear (26).

9. A positioning fixture for laser welding of automotive parts according to claim 8, characterized in that: The other end of the rotating shaft (24) is provided with a connector (25) connected to the two clamps (22). The connector (25) includes a swing arm (251) fixed to the end of the rotating shaft (24). The swing arm (251) is hinged to both sides and between the two clamps (22). The outer sides of the two clamps (22) are equipped with slides (23) that are slidably connected to the mounting shell (21).

10. A positioning fixture for laser welding of automotive parts according to claim 8, characterized in that: The rotating mechanism (3) includes a rotating shaft (31) and a servo motor (32). The rotating shaft (31) is mounted inside the mounting bracket (1). One end of the rotating shaft (31) is fixed to the outer wall of the mounting shell (21). The other end of the rotating shaft (31) is provided with a meshing transmission gear (33) between it and the output shaft of the servo motor (32).

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