White vehicle body top cover laser welding production line
By employing multiple welding components, robots, mounting frames, and positioning devices on the automotive production line, the problems of high floor space and cost in the co-production of multiple car models have been solved, achieving efficient and low-floor automated welding production.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- WUHAN FARLEY PLASMA CUTTING SYS CO LTD
- Filing Date
- 2025-06-11
- Publication Date
- 2026-05-15
AI Technical Summary
Existing automotive production lines face challenges such as time-consuming and costly manual fixture switching when producing multiple car models on the same line, or the need for a large floor space when designing multiple laser welding workstations.
Design a laser welding production line for body-in-white roofs, employing multiple first welding components and first robots, combined with mounting frames and positioning devices, to achieve automated welding of parts for different vehicle models, and reduce floor space and operational risks through building structure and dust removal system.
This technology reduces the floor space and operational risks of production lines when multiple models are produced on the same line, improves welding efficiency and quality, and reduces manual intervention time.
Smart Images
Figure CN224238503U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the field of automobile manufacturing equipment, and specifically relates to a laser welding production line for the roof of a white body. Background Technology
[0002] Currently, various automobile manufacturers are widely using laser welding to improve body strength and appearance quality. Laser welding of the roof, in particular, requires precise body positioning dimensions, and production line laser welding fixtures often employ specialized positioning grippers and clamps. When a production line needs to accommodate multiple vehicle models produced on the same line, one approach is to manually switch between different model clamps. This method requires production line shutdown for switching, necessitates personnel intervention, and is time-consuming, making it unsuitable for high-speed production tasks. Another approach is to design multiple laser welding workstations, but this method involves higher investment costs and requires more floor space. Utility Model Content
[0003] In view of the above problems, this application provides a laser welding production line for body-in-white roofs, which can reduce the floor space of the production line while meeting the welding requirements of more vehicle models.
[0004] This application provides a laser welding production line for a body-in-white roof, comprising a loading station, a welding station, and a grinding station arranged sequentially along the production line direction. The production line includes a first robot, first welding components, and a mounting frame. The first robot is located at the welding station; multiple first welding components are used to clamp and weld parts of different models. The first robot is used to move the first welding components closer to the parts located at the welding station to weld the parts at the welding station. The production line also includes a mounting frame, at least partially located at the welding station. The mounting frame includes a first platform and a second platform for supporting multiple first welding components. The first platform is located below the second platform, and a gap exists between the first platform and the second platform for parts to pass through. The first robot is mounted on the second platform.
[0005] In the above technical solution, by setting up multiple first welding components and enabling the first robot to drive and clamp different first welding components to move different body-in-white parts and weld different body-in-white parts, the laser welding production line for the body-in-white roof is adapted to different body-in-white parts. At the same time, by setting up a mounting frame and supporting multiple first welding components on a second platform, and placing the first robot on the second platform, the installation area required by the first welding components and the first robot is reduced, thereby reducing the installation area occupied by the production line. Thus, while the production line can weld different body-in-white parts, the installation area of the production line is reduced.
[0006] In some embodiments, the laser welding production line for the body-in-white roof further includes a first positioning device, which is disposed on the first platform and located at the welding station. The first positioning device includes multiple pairs of first limiting members arranged along the routing direction. Each pair of first limiting members consists of two movable members along a first direction. Each pair of first limiting members has a first limiting gap between them for limiting the movement of the part along the first direction. The first direction, the routing direction, and the gravity direction are perpendicular to each other.
[0007] In the above technical solution, the first positioning device is configured to include multiple pairs of first limiting members arranged along the routing direction, and each pair of first limiting members is movable along the first direction. Each pair of first limiting members has a first limiting gap for limiting the movement of the part along the first direction, so that the first positioning device can position different body-in-white parts.
[0008] In some embodiments, the first positioning device further includes two second limiting members, which are spaced apart along the routing direction and are used to restrict the movement of the part along the routing direction.
[0009] In the above technical solution, the movement of the body-in-white parts along the routing direction is restricted by two second limiting members, which is simple in structure and easy to implement.
[0010] In some embodiments, the laser welding production line for the body-in-white roof further includes a first chamber and a second chamber arranged along the routing direction. Along the direction of gravity, the first chamber and the second chamber are located between the first platform and the second platform. The first chamber is arranged around the outer periphery of the welding station, and the second chamber is arranged around the outer periphery of the grinding station.
[0011] In the above technical solution, by placing the first chamber outside the welding station, the risk of light damage to the operator's eyes caused by welding can be reduced. Especially when laser welding is used on the production line, the first chamber can reduce the risk of reflected laser damage to the operator's eyes. At the same time, by setting up the second chamber, the grinding station can be isolated, thereby reducing the risk of dust pollution from the grinding station polluting the operator's working environment.
[0012] In some embodiments, the laser welding production line for the body-in-white roof further includes a lighting device located inside the second chamber and disposed on the side of the second platform facing the first platform, the lighting device being used to provide light between the first platform and the second platform.
[0013] In the above technical solution, the lighting device is used to provide light between the first platform and the second platform so that the operator can observe the situation of the welding station and the grinding station, and facilitate the camera to collect images of the weld, thereby facilitating the operator to inspect the weld quality.
[0014] In some embodiments, the laser welding production line for the body-in-white roof further includes a dust removal system disposed on the second platform. The dust removal system has an intake end located inside the second chamber and an exhaust end located on the side of the second platform opposite to the first platform.
[0015] In the above technical solution, the dust removal system is set on the second platform to reduce the installation area required by the dust removal system.
[0016] In some embodiments, the first chamber and the second chamber are connected.
[0017] In the above technical solution, the first chamber and the second chamber are connected so that the dust removal system can clean the dust inside the first chamber and the second chamber at the same time.
[0018] In some embodiments, the body-in-white roof laser welding production line further includes a pre-welding station located between the loading station and the welding station along the routing direction; the body-in-white roof laser welding production line also includes a second positioning device, a third positioning device, a second robot, and a second welding assembly. The second positioning device is located at the loading station and is used to releasably fix the part located at the loading station; the third positioning device is located at the pre-welding station and is used to releasably fix the part located at the pre-welding station; the second robot is located at the pre-welding station; multiple second welding assemblies are used to clamp and weld parts of different models, and the second robot is used to releasably drive the second welding assembly to move between the second positioning device and the third positioning device, so as to move the part from the second positioning device to the third positioning device and pre-weld the part on the third positioning device.
[0019] In the above technical solution, by setting up a pre-welding station to pre-weld the body-in-white parts before welding, the risk of deformation of the body-in-white parts during the welding process is reduced, and the welding quality of the body-in-white parts is improved.
[0020] In some embodiments, the laser welding production line for the body-in-white roof further includes a conveying system for driving parts sequentially through the pre-welding station, the welding station, and the grinding station.
[0021] In the above technical solution, the parts are driven sequentially through the pre-welding station, welding station and grinding station by the conveying system, which is simple in structure and easy to implement.
[0022] In some embodiments, the laser welding production line for the body-in-white roof further includes a third robot and a third welding assembly. The third robot is located at the pre-welding station; multiple third welding assemblies are used to clamp parts of different sizes, and the third robot is used to releasably drive the third welding assemblies to move between the third positioning device and the conveying system, so as to move the parts from the third positioning device to the conveying system and pre-weld the parts on the conveying system located at the pre-welding station. Attached Figure Description
[0023] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0024] Figure 1 A schematic diagram of the portion of the laser welding production line for the roof of a white body provided in this embodiment of the utility model, located on the first platform.
[0025] Figure 2 A schematic diagram of the portion of the laser welding production line for the roof of a white body provided in this embodiment of the utility model, located on the second platform.
[0026] Figure 3 A schematic diagram of the structure of the first positioning device provided in an embodiment of this utility model;
[0027] Figure 4 This is a schematic diagram of the structure of the second positioning device provided in an embodiment of the present utility model;
[0028] Figure 5 This is a schematic diagram of the structure of the third positioning device provided in an embodiment of the present utility model. Detailed Implementation
[0029] The embodiments of this application will now be described in detail with reference to the accompanying drawings.
[0030] In the description of this application, it should be understood that the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.
[0031] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, unless otherwise stated, "a plurality of" means two or more.
[0032] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.
[0033] Currently, various automobile manufacturers are widely using laser welding to improve body strength and appearance quality. Laser welding of the roof, in particular, requires precise body positioning dimensions, and production line laser welding fixtures often employ specialized positioning grippers and clamps. When a production line needs to accommodate multiple vehicle models produced on the same line, one approach is to manually switch between different model clamps. This method requires production line shutdown for switching, necessitates personnel intervention, and is time-consuming, making it unsuitable for high-speed production tasks. Another approach is to design multiple laser welding workstations, but this method involves higher investment costs and requires more floor space.
[0034] To solve the above technical problems, refer to Figure 1 and Figure 2 This application provides a laser welding production line for a body-in-white roof, comprising a loading station 10A, a welding station 30A, and a grinding station 40A arranged sequentially along the X-direction. The production line includes a first robot 31, first welding components 32, and a mounting frame. The first robot 31 is located at the welding station 30A. Multiple first welding components 32 are used to clamp and weld parts 200 of different models. The first robot 31 is used to move the first welding components 32 closer to the parts 200 located at the welding station 30A for welding. The laser welding production line also includes a mounting frame, at least partially located at the welding station 30A. The mounting frame includes a first platform 110 and a second platform 120 for supporting multiple first welding components 32. The first platform 110 is located below the second platform 120, and a gap exists between the first platform 110 and the second platform 120 for the parts 200 to pass through. The first robot 31 is mounted on the second platform 120.
[0035] For example, the loading station 10A is a station for providing the white body part 200 to the production line by the operator, the welding station 30A is a station for welding the white body part 200 on the production line, and the grinding station 40A is a station for grinding the weld seams on the part 200.
[0036] In some implementations, welding station 30A is equipped with a robot with a welding gun head, and grinding station 40A is equipped with a robot with a flexible grinding head and a weld inspection robot. The flexible grinding head can stably maintain a constant grinding pressure. The robot works with the flexible grinding head to grind the laser weld of the top cover to ensure the appearance quality of the weld. The weld inspection robot works with a vision inspection head to inspect the quality of the weld.
[0037] The mounting frame is a mounting frame with two platforms. In some embodiments, the body-in-white roof laser welding production line also includes a conveyor system 50, which is disposed on the first platform 110.
[0038] In this technical solution, by setting up multiple first welding components 32, and enabling the first robot 31 to drive and clamp different first welding components 32 to move different body-in-white parts 200, and to weld different body-in-white parts 200, the laser welding production line for the body-in-white roof is adapted to different body-in-white parts 200. At the same time, by setting up a mounting frame and supporting the multiple first welding components 32 on the second platform 120, and setting the first robot 31 on the second platform 120, the installation area required by the first welding components 32 and the first robot 31 is reduced, thereby reducing the installation area occupied by the production line. Thus, while the production line can weld different body-in-white parts 200, the installation area of the production line is reduced.
[0039] According to some embodiments of this application, please refer to Figure 1 and Figure 3 The laser welding production line for the roof of the white body also includes a first positioning device 33. The first positioning device 33 is set on the first platform 110 and located at the welding station 30A. The first positioning device 33 includes multiple pairs of first limiting members 331 arranged along the routing direction X. Each pair of first limiting members 331 consists of two movable members along the first direction. Each pair of first limiting members 331 has a first limiting gap between them for limiting the movement of the part 200 along the first direction. The first direction, the routing direction X and the gravity direction Z are perpendicular to each other.
[0040] It is understood that the first positioning device 33 includes a first frame and a first limiting member 331. The first limiting member 331 consists of multiple pairs of first limiting members 331 arranged along the routing direction X on the first frame, and each pair of first limiting members 331 consists of two movable members along the first direction. For example, a first driving mechanism is provided on the first frame. The first driving mechanism is used to drive the first limiting member 331 to move along the first direction to clamp the two edges of the body-in-white part 200 that are disposed opposite to each other in the first direction. It is understood that when the body-in-white part 200 is disposed on the first positioning device 33, the length direction of the body-in-white part 200 may be parallel to the first direction, and / or the width direction of the body-in-white part 200 may be parallel to the first direction.
[0041] For example, the first drive mechanism may be a linear module or a cylinder.
[0042] In this technical solution, the first positioning device 33 is configured to include multiple pairs of first limiting members 331 arranged along the routing direction X, and each pair of first limiting members 331 is movable along the first direction. Each pair of first limiting members 331 has a first limiting gap for limiting the movement of the part 200 along the first direction, so that the first positioning device 33 can position different body-in-white parts 200.
[0043] According to some embodiments of this application, please refer to Figure 1 and Figure 3 The first positioning device 33 also includes two second limiting members 332, which are spaced apart along the routing direction X. The two second limiting members 332 are used to restrict the movement of the part 200 along the routing direction X.
[0044] It is understood that the first positioning device 33 includes a first frame and a second limiting member 332, wherein two second limiting members 332 are spaced apart on the first frame along the routing direction X. Exemplarily, a second driving mechanism is provided on the first frame, which is used to drive the second limiting members 332 to move along the routing direction X to clamp the two edges of the body-in-white part 200 that are disposed opposite to each other in the routing direction X.
[0045] For example, the second drive mechanism can be a linear module or a cylinder.
[0046] Understandably, the limiting elements mentioned above and below can be one or more of a locating pin, a locating block, or a locating shaft.
[0047] In this technical solution, the movement of the body-in-white part 200 along the routing direction X is restricted by two second limiting members 332, which is simple in structure and easy to implement.
[0048] According to some embodiments of this application, please refer to Figure 1 The white body roof laser welding production line also includes a first chamber 34 and a second chamber 41 arranged along the X direction of the line. Along the Z direction of gravity, the first chamber 34 and the second chamber 41 are located between the first platform 110 and the second platform 120. The first chamber 34 is arranged around the outer periphery of the welding station 30A, and the second chamber 41 is arranged around the outer periphery of the grinding station 40A.
[0049] In this technical solution, by placing the first chamber 34 outside the welding station 30A, the risk of light damage to the operator's eyes caused by welding can be reduced. Especially when laser welding is used on this production line, the first chamber 34 can reduce the risk of reflected laser damage to the operator's eyes. At the same time, by setting the second chamber 41, the grinding station 40A can be isolated, thereby reducing the risk of dust pollution from the grinding station 40A affecting the operator's working environment.
[0050] According to some embodiments of this application, please refer to Figure 1 and Figure 2 The laser welding production line for the white body roof also includes a lighting device 42, which is located inside the second chamber 41 and is set on the side of the second platform 120 facing the first platform 110. The lighting device 42 is used to provide light between the first platform 110 and the second platform 120.
[0051] In some embodiments, the lighting device 42 may also provide light into the second room 41, and the lighting device 42 may also include an air conditioner for regulating the temperature inside the second room 41 to provide a constant temperature environment. Exemplarily, the lighting device 42 may be a light source room.
[0052] In this technical solution, the lighting device 42 is used to provide light between the first platform 110 and the second platform 120, so that the operator can observe the situation of the welding station 30A and the grinding station 40A, and facilitate the camera to capture images of the weld, thereby facilitating the operator to inspect the weld quality.
[0053] According to some embodiments of this application, please refer to Figure 1 and Figure 2 The white body roof laser welding production line also includes a dust removal system 43, which is located on the second platform 120. The dust removal system 43 has an air intake end located in the second chamber 41 and an exhaust end located on the side of the second platform 120 away from the first platform 110.
[0054] For example, the dust removal system 43 is connected to the second chamber 41 through its duct suction end to treat the smoke and dust inside the second chamber 41.
[0055] In some embodiments, the dust removal system 43 can also adjust the humidity in the second housing 41 to provide a constant humidity environment.
[0056] In this technical solution, by arranging the dust removal system 43 on the second platform 120, the installation area occupied by the dust removal system 43 can be reduced.
[0057] According to some embodiments of the present application, the first housing 34 and the second housing 41 are connected.
[0058] In some embodiments, the first housing 34 and the second housing 41 are provided with openings that communicate with each other. A first door body for closing the opening is provided on the first housing 34, and a second door body for closing the opening is provided on the second housing 41.
[0059] In this technical solution, the first housing 34 and the second housing 41 are connected so that the dust removal system 43 can simultaneously clean the dust in the first housing 34 and the second housing 41.
[0060] According to some embodiments of the present application, please refer to Figure 1 and Figure 4 , the white body roof laser welding production line further has a pre-welding station 20A located between the loading station 10A and the welding station 30A along the wire routing direction X; the white body roof laser welding production line further includes a second positioning device 11, a third positioning device 24, a second robot 22 and a second welding assembly 23. The second positioning device 11 is located at the loading station 10A, and the second positioning device 11 is used to releasably fix the part 200 located at the loading station 10A; the third positioning device 24 is located at the pre-welding station 20A, and the third positioning device 24 is used to releasably fix the part 200 located at the pre-welding station 20A; the second robot 22 is located at the pre-welding station 20A; a plurality of second welding assemblies 23 are used to clamp and weld parts 200 of different models, and the second robot 22 is used to releasably drive the second welding assembly 23 to move between the second positioning device 11 and the third positioning device 24, so as to drive the part 200 to move from the second positioning device 11 to the third positioning device 24 and pre-weld the part 200 on the third positioning device 24.
[0061] The pre-welding station 20A is a station for spot welding the white body parts 200 so that the white body parts 200 are initially fixed.
[0062] In some embodiments, the second positioning device 11 includes a limit frame 111 and a trolley 112. The limit frame 111 is in an inverted U shape. One side of the limit frame 111 is an open side for the trolley 112 to enter. The trolley 112 is used to carry the white body part 200. When the trolley 112 is located within the limit frame 111, the trolley 112 cooperates with the limit frame 111 to limit the movement of the white body part 200.
[0063] In this technical solution, by setting a pre-welding station 20A, the body-in-white part 200 is pre-welded before welding, thereby reducing the risk of deformation of the body-in-white part 200 during the welding process and improving the welding quality of the body-in-white part 200.
[0064] According to some embodiments of this application, the laser welding production line for the roof of a white body also includes a conveying system 50, which is used to drive the parts 200 sequentially through the pre-welding station 20A, the welding station 30A and the grinding station 40A.
[0065] For example, the conveying system 50 can be a conveying roller bed.
[0066] In some embodiments, the conveying system 50 includes a first conveying roller bed 51, a second conveying roller bed 52, and a third conveying roller bed 53 that are interconnected, wherein the first conveying roller bed 51 is located at the pre-welding station 30A, the second conveying roller bed 52 is located at the welding station 30A, and the third conveying roller bed 53 is located at the grinding station 40A.
[0067] Understandably, the robots are distributed along the conveyor system 50.
[0068] In this technical solution, the conveying system 50 drives the part 200 through the pre-welding station 20A, the welding station 30A and the grinding station 40A in sequence, which is simple in structure and easy to implement.
[0069] According to some embodiments of this application, please refer to Figure 1 and Figure 5 The laser welding production line for the body-in-white roof also includes a third robot 25 and a third welding assembly 26. The third robot 25 is located at the pre-welding station 20A; multiple third welding assemblies 26 are used to clamp parts 200 of different models. The third robot 25 is used to releasably drive the third welding assemblies 26 between the third positioning device 24 and the conveying system 50 to move the parts 200 from the third positioning device 24 to the conveying system 50 and to pre-weld the parts 200 located on the conveying system 50 at the pre-welding station 20A.
[0070] In some embodiments, the third positioning device 24 includes a third frame and a third limiting member 241. The third limiting member 241 is a plurality of members arranged around the periphery of the third frame. For example, a third driving mechanism is provided on the third frame. The third driving mechanism is used to drive the third limiting member 241 to move radially along the third frame to fix the periphery of the body-in-white part 200.
[0071] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other.
[0072] The above embodiments are only used to illustrate the technical solutions of this application and are not intended to limit this application. For those skilled in the art, this application can have various modifications and variations. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.
Claims
1. A laser welding production line for a white body roof, comprising a feeding station, a welding station, and a grinding station arranged sequentially along the production line direction, characterized in that, The laser welding production line for the body-in-white roof includes: The first robot is located at the welding station; Multiple first welding assemblies are used to clamp and weld parts of different types, and the first robot is used to releasably move the first welding assemblies close to the parts located at the welding station to weld the parts at the welding station. The laser welding production line for the body-in-white roof also includes a mounting frame, which is at least partially located at the welding station. The mounting frame includes a first platform and a second platform for supporting multiple first welding components. The first platform is located below the second platform, and there is a gap between the first platform and the second platform for parts to pass through. The first robot is mounted on the second platform.
2. The laser welding production line for the roof of a white body according to claim 1, characterized in that, The laser welding production line for the body-in-white roof also includes: A first positioning device is disposed on the first platform and located at the welding station. The first positioning device includes multiple pairs of first limiting members arranged along the routing direction. Each pair of first limiting members consists of two movable members along a first direction. Each pair of first limiting members has a first limiting gap between them for limiting the movement of the part along the first direction. The first direction, the routing direction, and the gravity direction are perpendicular to each other.
3. The laser welding production line for the roof of a white body according to claim 2, characterized in that, The first positioning device further includes: Two second limiting members are provided at intervals along the routing direction, and the two second limiting members are used to restrict the movement of the part along the routing direction.
4. The laser welding production line for the roof of a white body according to claim 1, characterized in that, The laser welding production line for the body-in-white roof also includes: The first chamber and the second chamber are arranged along the routing direction. Along the direction of gravity, the first chamber and the second chamber are located between the first platform and the second platform. The first chamber is arranged around the outer periphery of the welding station, and the second chamber is arranged around the outer periphery of the grinding station.
5. The laser welding production line for the roof of a white body according to claim 4, characterized in that, The laser welding production line for the body-in-white roof also includes: A lighting device is located inside the second chamber and is disposed on the side of the second platform facing the first platform. The lighting device is used to provide light between the first platform and the second platform.
6. The laser welding production line for the roof of a white body according to claim 4, characterized in that, The laser welding production line for the body-in-white roof also includes: A dust removal system is installed on the second platform, the dust removal system having an air intake end located inside the second chamber and an exhaust end located on the side of the second platform opposite to the first platform.
7. The laser welding production line for the roof of a white body according to claim 6, characterized in that, The first chamber and the second chamber are connected.
8. The laser welding production line for the roof of a white body according to claim 1, characterized in that, The white body roof laser welding production line also has a pre-welding station located between the loading station and the welding station along the routing direction; The laser welding production line for the body-in-white roof also includes: A second positioning device is located at the loading station, and the second positioning device is used to releasably fix the part located at the loading station; A third positioning device is located at the pre-welding station, and the third positioning device is used to releasably fix the part located at the pre-welding station; The second robot is located at the pre-welding station; Multiple second welding assemblies are used to clamp and weld parts of different sizes. The second robot is used to releasably drive the second welding assemblies between the second positioning device and the third positioning device to move parts from the second positioning device to the third positioning device and to pre-weld parts on the third positioning device.
9. The laser welding production line for the roof of a white body according to claim 8, characterized in that, The laser welding production line for the body-in-white roof also includes: A conveying system is used to drive the parts sequentially through the pre-welding station, the welding station, and the grinding station.
10. The laser welding production line for the roof of a white body according to claim 9, characterized in that, The laser welding production line for the body-in-white roof also includes: The third robot is located at the pre-welding station; Multiple third welding assemblies are used to clamp parts of different sizes. The third robot is used to releasably drive the third welding assemblies to move between the third positioning device and the conveying system, so as to move the parts from the third positioning device to the conveying system and pre-weld the parts on the conveying system and located at the pre-welding station.