CN118617018B - A welding tool for automobile body - Google Patents

Abstract

The invention relates to the technical field of welding tools, and particularly provides a welding tool for an automobile body; the fixture comprises a fixture frame, wherein a beam positioning assembly for synchronously positioning a plurality of beams of a vehicle body structure is assembled on the fixture frame, two longitudinal beam positioning mechanisms for positioning and butting two longitudinal beams of the vehicle body structure with the plurality of beams are assembled on the fixture frame, and the two longitudinal beam positioning mechanisms are horizontally and symmetrically distributed on two sides of the beam positioning assembly; the tooling provided by the invention can be used for rapidly completing one-step automatic positioning, clamping and butt joint of the longitudinal beam and the cross beam in the frame before welding, and completing one-step loosening and clamping of the frame after welding, so that one-step rapid operation can be realized, the clamping and loosening operations are not required to be performed manually one by one, and the convenience and the overall efficiency of the operation are improved.

Description

A welding tool for automobile body

Technical Field

The invention relates to the technical field of welding tooling, and specifically provides a welding tooling for an automobile body.

Background Art

The automobile body is an important part of the automobile as the overall frame shell structure. According to the different forces of the body structure, the automobile body can be divided into a non-load-bearing body, a semi-load-bearing body and a load-bearing body. Both the non-load-bearing body and the semi-load-bearing body are composed of a main body and a frame. The non-load-bearing body has a complete frame, while the semi-load-bearing frame has a partial frame. Among them, the frame of the non-load-bearing body is divided into multiple structures. FIG5 shows one of the frame-type frame structures, which is generally composed of two longitudinal beams and multiple cross beams assembled and welded. In the existing production and manufacturing process, for In order to improve production efficiency, welding fixtures are often used to clamp and position the frame. However, existing welding fixtures are generally designed with multiple independent clamping and positioning components for the longitudinal beams and cross beams. In actual operation, it is necessary to manually complete the clamping and positioning of the cross beams and longitudinal beams one by one. There is no linkage between the positioning structures. Therefore, whether it is clamping and positioning before welding or loosening the clamping after welding, it is necessary to operate one by one, which is troublesome and inefficient. In addition, one-by-one operations need to ultimately ensure the effective assembly and docking of the longitudinal beams and the cross beams, so multiple fine-tuning is often required.

Summary of the invention

In order to solve the above problems, the present invention provides a welding tool for an automobile body, which is used to solve the problems mentioned in the above background technology.

In order to achieve the above-mentioned purpose, the present invention adopts the following technical scheme: a welding tool for an automobile body, including a tool frame, on which is mounted a beam positioning assembly for synchronously positioning multiple beams of a vehicle body structure, and on which are mounted two longitudinal beam positioning mechanisms for positioning and docking two longitudinal beams of the vehicle body structure with multiple beams, wherein the two longitudinal beam positioning mechanisms are horizontally symmetrically distributed on both sides of the beam positioning assembly.

The beam positioning assembly includes a plurality of beam positioning mechanisms which are horizontally and linearly distributed and installed on a tooling frame and are used to clamp and position a plurality of beams in a one-to-one correspondence. The tooling frame is equipped with a driving component which is used to synchronously drive a plurality of beam positioning mechanisms to implement clamping.

The longitudinal beam positioning mechanism includes a main clamping beam used for clamping contact with the longitudinal beam and linked with multiple cross beam positioning mechanisms. The main clamping beam is slidably installed on the tooling frame along the symmetrical setting direction of the two longitudinal beam positioning mechanisms; when the multiple cross beam positioning mechanisms clamp the cross beam, the two main clamping beams move towards each other; end clamping assemblies for clamping and positioning the two ends of the longitudinal beam are symmetrically installed on the main clamping beam at both ends in the length direction.

Preferably, the beam positioning mechanism comprises a support platform fixed on the tooling frame for supporting and placing the beam, and the support platform is symmetrically slidably driven and installed with two side clamping components in the length direction of the main clamping beam.

Preferably, the side clamping component includes a sliding bracket slidably mounted on a supporting platform, a roller frame is slidably mounted on the sliding bracket along its sliding direction, the roller frame is located on the side of the sliding bracket close to the other side clamping component, the roller frame is elastically connected to the sliding bracket, a plurality of clamping rollers are vertically mounted on the roller frame, and the plurality of clamping rollers are horizontally and linearly distributed in a direction perpendicular to the sliding direction of the sliding bracket.

Preferably, a bidirectional screw is horizontally rotatably installed on the support platform, and the axial direction of the bidirectional screw is perpendicularly arranged relative to the sliding direction of the sliding bracket. The two threaded sections of the bidirectional screw are correspondingly threadedly connected with a hinge seat, and two connecting rods are vertically rotatably hinged on the two hinge seats, and the two connecting rods are hinged to the two sliding brackets one by one.

Preferably, a double-headed telescopic rod is connected between the two articulated seats on the same bidirectional screw and the adjacent main clamping beams, the two telescopic ends of the double-headed telescopic rod are respectively hinged on the articulated seat and the main clamping beam, and the non-telescopic end of the double-headed telescopic rod is horizontally rotatably installed on the tooling frame.

Preferably, a gear is fixed on the bidirectional lead screw; the driving assembly includes a rack that is horizontally driven and slidably mounted on the tooling frame, and a plurality of the gears are meshed together on the rack.

Preferably, the double-headed telescopic pull rod includes a central tube and two sliding rods relatively slidably mounted at both ends of the central tube; a series shaft is horizontally fixedly installed adjacent to the two main clamping beams on the tooling frame, and the central tubes of the multiple double-headed telescopic pull rods connected to the same main clamping beam are rotatably mounted together on the corresponding series shafts; one end of one of the sliding rods is hinged on the hinged seat, and one end of the other sliding rod is hinged on the main clamping beam.

Preferably, a plurality of guide rods slidably mounted on the sliding bracket are horizontally fixed on the roller frame, a clamping spring is sleeved on the guide rods, and two ends of the clamping spring are respectively fixed on the sliding bracket and the roller frame.

Preferably, the tooling frame is provided with a plurality of supporting plates which are distributed alternately with the plurality of beam positioning mechanisms.

Preferably, the end clamp assembly comprises an end clamp plate which is slidably mounted on the main clamp beam along the length direction of the main clamp beam.

The above technical scheme has the following advantages or beneficial effects: the present invention provides a welding tool for an automobile body, the tool provided by the present invention is provided with a beam positioning assembly for positioning and clamping multiple beams, and a longitudinal beam positioning mechanism for two longitudinal beams, the beam positioning assembly is provided with multiple beam positioning mechanisms for synchronous drive clamping, and the longitudinal beam positioning mechanism and the drive of the multiple beam positioning mechanisms are linked, so that the longitudinal beams and the cross beams in the frame can be quickly and automatically positioned, clamped and docked in one step before welding, and the frame can be released and clamped in one step after welding, which can realize one-step quick operation without manual clamping and unclamping operations one by one, thereby improving the convenience of operation and overall efficiency; in addition, the tool provided by the present invention provides stable and reliable clamping and positioning, which on the one hand ensures the pressing contact at the welding point between the beam and the longitudinal beam, avoids the generation of false welding, and ensures the strength of the weld, and on the other hand avoids the movement and dislocation of the beam and the longitudinal beam during welding, and ensures the consistency of the size structure of all welded and formed frames.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention and its features, configurations and advantages will become more apparent by reading the detailed description of non-limiting embodiments with reference to the following drawings. The same reference numerals indicate the same parts throughout the drawings, which are not drawn to scale, with emphasis on illustrating the subject matter of the present invention.

FIG. 1 is a perspective schematic diagram of a welding tool for an automobile body provided by the present invention.

FIG. 2 is a three-dimensional structural diagram of the assembly of the crossbeam positioning assembly and the longitudinal beam positioning mechanism.

FIG. 3 is a partial enlarged view of point A in FIG. 2 .

FIG. 4 is a three-dimensional structural diagram of the assembly structure shown in FIG. 2 at another viewing angle.

FIG. 5 is a schematic structural diagram of a vehicle frame.

FIG. 6 is a three-dimensional view of a working state of a welding tool for an automobile body provided by the present invention.

FIG. 7 is a top view of a welding tool for an automobile body provided by the present invention in a working state.

FIG8 is a cross-sectional view taken along line B-B in FIG7.

FIG9 is a cross-sectional view taken along line C-C in FIG7 .

FIG. 10 is a partial enlarged view of point D in FIG. 8 .

In the figure: 1, tooling frame; 11, side plate; 12, baffle; 121, guide rail; 13, support plate; 2, beam positioning assembly; 21, drive assembly; 211, drive cylinder; 212, rack; 22, beam positioning mechanism; 221, support platform; 2211, slideway; 222, side clamping member; 2221, sliding bracket; 2222, roller frame; 2223, clamping roller; 2224, guide rod; 2225 , clamping spring; 223, two-way lead screw; 2231, gear; 224, hinged seat; 225, connecting rod; 3, longitudinal beam positioning mechanism; 31, main clamping beam; 311, guide column; 312, slide rail; 32, double-head telescopic pull rod; 321, center tube; 322, slide rod; 33, serial shaft; 34, end clamp assembly; 341, end clamp cylinder; 342, end clamp plate; 4, frame; 41, longitudinal beam; 42, cross beam.

DETAILED DESCRIPTION

The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

In order to enable those skilled in the art to better understand the scheme of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments.

A welding tool for an automobile body. The welding tool provided by the present invention is mainly used to cooperate with an existing automatic welding machine (manual welding is not excluded) to perform welding, positioning, and docking assembly on a frame 4 as shown in FIG5 . The frame 4 as shown in FIG5 is a frame part of a non-load-bearing body of a certain type of vehicle, and is a peripheral frame structure with rectangular frame characteristics. Its main body is welded and assembled by two longitudinal beams 41 and six cross beams 42. In this embodiment, the cross beams 42 of the frame 4 of the model shown in the figure are of the same size structure, and multiple cross beams 42 are evenly distributed.

As shown in Figures 1, 7, 8 and 9, the welding tooling includes a tooling frame 1, which includes two side panels 11, and five horizontal straight and evenly distributed supporting plates 13 are horizontally welded between the two side panels 11. The five supporting plates 13 together constitute a placement table for horizontally placing two longitudinal beams 41. A baffle plate 12 is horizontally welded between the two side panels 11, and the baffle plate 12 is located below the supporting plate 13.

As shown in Fig. 2, Fig. 3, Fig. 4, Fig. 8, Fig. 9 and Fig. 10, the tooling frame 1 is equipped with a beam positioning assembly 2 for synchronously positioning six beams 42. The beam positioning assembly 2 includes six horizontal straight lines evenly distributed on the tooling frame 1 and used for clamping and positioning the six beams 42 one by one. The six beam positioning mechanisms 22 and the five supporting plates 13 are evenly distributed and arranged alternately. The beam positioning mechanism 22 includes a support platform 221 welded on the baffle plate 12 for supporting and placing the beams 42. The support platform 221 is symmetrically provided with slide grooves 2211 on both sides. The slide grooves 2211 extend along the distribution direction of the five supporting plates 13. A side clamping component 222 is symmetrically provided and slidably installed between the two slide grooves 2211. The side clamping component 222 includes a sliding bracket 2221 slidably installed between the two slide grooves 2211. The sliding bracket 2221 is provided with a roller frame 22 on one side close to the other side clamping component 222. 22. Two guide rods 2224 that slide with the sliding bracket 2221 are welded on the roller frame 2222. The guide rods 2224 are axially along the sliding direction of the sliding bracket 2221. A clamping spring 2225 is sleeved on the guide rod 2224, and the two ends of the clamping spring 2225 are respectively welded to the sliding bracket 2221 and the roller frame 2222; a plurality of clamping rollers 2223 are vertically rotatably installed on the roller frame 2222, and the plurality of clamping rollers 2223 are evenly distributed in a horizontal straight line in a direction perpendicular to the sliding direction of the sliding bracket 2221. A bidirectional lead screw 223 is horizontally rotatably installed on the supporting platform 221. The axial direction of the bidirectional lead screw 223 is perpendicularly arranged relative to the sliding direction of the sliding bracket 2221. The two threaded sections of the bidirectional lead screw 223 are correspondingly threadedly connected with a hinge seat 224. Two hinge seats 224 are vertically rotatably hinged with two connecting rods 225, and the two connecting rods 225 are hinged to the two sliding brackets 2221 one by one. A gear 2231 is fixed on the bidirectional lead screw 223. The tooling frame 1 is equipped with a driving assembly 21 for synchronously driving six beam positioning mechanisms 22 to implement clamping; a guide rail 121 extending along the distribution direction of the five supporting plates 13 is welded to the upper end surface of the baffle 12, and the driving assembly 21 includes a rack 212 slidably mounted on the guide rail 121, and a driving cylinder 211 is horizontally fixedly mounted on the bottom end surface of the baffle 12 through a fixing plate, and one end of the rack 212 is connected to the output end of the driving cylinder 211 through a connecting plate, and the gears 2231 in the six beam positioning mechanisms 22 are meshed together on the rack 212.

As shown in Figures 2, 3, 4, 8, 9 and 10, the tooling frame 1 is equipped with two longitudinal beam positioning mechanisms 3 for positioning and docking the two longitudinal beams 41 with the six cross beams 42. The two longitudinal beam positioning mechanisms 3 are horizontally and symmetrically distributed on both sides of the cross beam positioning assembly 2. The longitudinal beam positioning mechanism 3 includes a main clamping beam 31 for clamping contact with the longitudinal beam 41. A plurality of guide columns 311 are horizontally welded on the side wall end surface of the main clamping beam 31 that is located away from the clamping contact surface. The plurality of guide columns 311 are evenly distributed in the length direction of the main clamping beam 31, and the plurality of guide columns 311 are slidably installed together on the side plates 11 at adjacent positions; a double-headed telescopic pull rod 32 is connected between the two articulated seats 224 on the same bidirectional lead screw 223 and the adjacent main clamping beams 31. The double-headed telescopic pull rod 32 is connected to the two articulated seats 224 on the same bidirectional lead screw 223 and the adjacent main clamping beams 31. The telescopic pull rod 32 includes a central tube 321 and two sliding rods 322 relatively slidably mounted at both ends of the central tube 321; a horizontally welded series shaft 33 is arranged adjacent to the two main clamping beams 31 on the tooling frame 1, and the central tube 321 of the six double-headed telescopic pull rods 32 connected to the same main clamping beam 31 is rotatably mounted on the corresponding series shaft 33; one end of one of the sliding rods 322 is hinged on the hinge seat 224, and one end of the other sliding rod 322 is hinged on the main clamping beam 31. End clamp assemblies 34 for clamping and positioning the two ends of the longitudinal beam 41 are symmetrically installed at both ends of the main clamp beam 31 in the length direction; slide rails 312 are welded on the main clamp beam 31 corresponding to the two end clamp assemblies 34, and the direction of the slide rails 312 is along the length direction of the main clamp beam 31. The end clamp assembly 34 includes an end clamp plate 342 slidably installed on the slide rail 312 and an end clamp cylinder 341 fixed on the main clamp beam 31, and the end clamp plate 342 is fixed to the output end of the end clamp cylinder 341.

The present invention provides a welding tool for an automobile body, which can automatically position, clamp and connect a longitudinal beam 41 and multiple cross beams 42 in a frame 4 before welding the frame 4 shown in FIG. 5 . The specific process is as follows; the working state is shown in FIGS. 6 and 7 .

Before positioning and clamping, in order to facilitate the placement of the longitudinal beam 41 and multiple cross beams 42, the distance between the two side clamping parts 222 in each cross beam positioning mechanism 22, the distance between the two main clamping beams 31, and the distance between the two end clamping plates 342 on each main clamping beam 31 can be adjusted to the maximum state.

Subsequently, the six cross beams 42 are placed one by one on the six supporting platforms 221, and the two longitudinal beams 41 are placed on the supporting plate 13; then, the driving cylinder 211 is started to drive the rack 212 to slide, and the four end clamping cylinders 341 are started synchronously. On the one hand, the rack 212 synchronously drives the six gears 2231, so that the six bidirectional lead screws 223 rotate synchronously, and the two articulated seats 224 on the bidirectional lead screws 223 move back to back, and the articulated seats 224 drive the two sliding brackets 2221 to slide toward each other through the connecting rod 225, and then clamp the cross beam 42 between the two sets of clamping rollers 2223; at the same time, on the other hand, the six articulated seats 224 on the same side drive the main clamping beam 31 on the same side to move to the other side through the double-headed telescopic pull rod 32 during the movement. The side main clamping beam 31 approaches and slides, and the main clamping beam 31 will be in close contact with the longitudinal beam 41 during the sliding process, and the two end clamping plates 342 located on the main clamping beam 31 are close and slide under the drive of the end clamping cylinder 341, and then the two ends of the longitudinal beam 41 are clamped between the two end clamping plates 342, and then the positions of the two ends of the longitudinal beam 41 are straightened. In the process of the two main clamping beams 31 approaching each other, according to the placement state, one end of the cross beam 42 will contact one of the main clamping beams 31, and then, with the auxiliary rolling of the two sets of clamping rollers 2223, the main clamping beam 31 will push the cross beam 42 to move toward the other main clamping beam 31. Finally, the six cross beams 42 are all clamped in the center between the two longitudinal beams 41. At this point, the automatic positioning, clamping and docking of the two longitudinal beams 41 and the six cross beams 42 are completed.

Before formal welding, in order to avoid welding, the end clamping plate 342 can be separated from the end of the longitudinal beam 41, and the two end clamping plates 342 on the main clamping beam 31 can be moved to the maximum spacing state. Then, the welding of each cross beam 42 and the joints between the two longitudinal beams 41 can be completed in sequence along the length direction of the longitudinal beam 41; after welding is completed, the driving cylinder 211 is started again to make the rack 212 slide in the opposite direction, so that the clamping of the longitudinal beam 41 and the cross beam 42 can be quickly and synchronously released. Finally, the frame 4 that has been welded can be removed.

The tooling provided by the present invention is provided with a beam positioning assembly 2 for positioning and clamping multiple beams 42 and a longitudinal beam positioning mechanism 3 for two longitudinal beams 41. The beam positioning assembly 2 is provided with multiple beam positioning mechanisms 22 for synchronous drive clamping, and the longitudinal beam positioning mechanism 3 is linked with the drive of the multiple beam positioning mechanisms 22, so that the longitudinal beams 41 and the beams 42 in the frame 4 can be quickly and automatically positioned, clamped and docked in one step before welding, and the frame can be released and clamped in one step after welding, which can achieve one-step quick operation without manual clamping and unclamping operations one by one, thereby improving the convenience and efficiency of operation; in addition, the tooling provided by the present invention provides stable and reliable clamping and positioning, which on the one hand ensures the pressing contact at the welding point between the beam 42 and the longitudinal beam 41, avoids the generation of false welding, and ensures the strength of the weld; on the other hand, it avoids the movement and dislocation of the beam 42 and the longitudinal beam 41 during welding, and ensures the consistency of the size structure of all the frames 4 after welding.

In the description of the present invention, it is to be understood that the terms “center”, “longitudinal”, “lateral”, “length”, “width”, “thickness”, “up”, “down”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, “clockwise”, “counterclockwise”, “axial”, “radial”, “circumferential”, etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "connect", "install", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood by specific circumstances.

The above describes the preferred embodiments of the present invention. It should be understood that the present invention is not limited to the above-mentioned specific embodiments, and the devices and structures that are not described in detail should be understood to be implemented in a common manner in the art; any technician familiar with the art can make many possible changes and modifications without departing from the technical solution of the present invention, or modify them into equivalent embodiments with equivalent changes, which does not affect the essential content of the present invention. Therefore, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of protection of the technical solution of the present invention.

Claims (4)

1. The utility model provides a welding frock of car automobile body which characterized in that: the automatic positioning device for the automobile body comprises a tool rack (1), wherein a plurality of cross beams (42) for the automobile body structure are synchronously positioned on the tool rack (1), two longitudinal beam positioning mechanisms (3) for positioning and butting two longitudinal beams (41) of the automobile body structure with the plurality of cross beams (42) are assembled on the tool rack (1), and the two longitudinal beam positioning mechanisms (3) are horizontally and symmetrically distributed on two sides of the cross beam positioning assembly (2); wherein:

The beam positioning assembly (2) comprises a plurality of beam positioning mechanisms (22) which are horizontally and linearly arranged on the tool rack (1) and are used for clamping and positioning a plurality of beams (42) in a one-to-one correspondence manner, and a driving assembly (21) for synchronously driving the plurality of beam positioning mechanisms (22) to clamp is arranged on the tool rack (1);

The longitudinal beam positioning mechanisms (3) comprise main clamping beams (31) which are used for being in clamping contact with the longitudinal beams (41) and are arranged in linkage with the plurality of transverse beam positioning mechanisms (22), and the main clamping beams (31) are slidably arranged on the tool rack (1) along the symmetrical arrangement direction of the two longitudinal beam positioning mechanisms (3); when a plurality of the beam positioning mechanisms (22) clamp the beams (42), the two main clamping beams (31) move towards each other; end clamp assemblies (34) used for clamping and positioning two ends of the longitudinal beam (41) are symmetrically arranged on two ends of the main clamping beam (31) in the length direction;

The beam positioning mechanism (22) comprises a bearing table (221) which is fixed on the tool rack (1) and used for bearing and placing the beam (42), and the bearing table (221) is symmetrically and slidingly driven to be provided with two side clamping components (222) in the length direction of the main clamping beam (31);

The side clamping component (222) comprises a sliding support (2221) which is slidably arranged on the bearing platform (221), a roller frame (2222) is slidably arranged on the sliding support (2221) along the sliding direction of the sliding support, the roller frame (2222) is positioned on one side, close to the other side clamping component (222), of the sliding support (2221), the roller frame (2222) is elastically connected with the sliding support (2221), a plurality of clamping rollers (2223) are vertically and rotatably arranged on the roller frame (2222), and the clamping rollers (2223) are horizontally and linearly distributed in the direction perpendicular to the sliding direction of the sliding support (2221);

The two-way screw rod (223) is horizontally rotatably arranged on the bearing platform (221), the axial direction of the two-way screw rod (223) is vertically arranged relative to the sliding direction of the sliding support (2221), two threaded sections of the two-way screw rod (223) are correspondingly connected with hinge bases (224) through threads, two connecting rods (225) are vertically rotatably hinged on the two hinge bases (224), and the two connecting rods (225) are hinged on the two sliding supports (2221) in a one-to-one correspondence manner;

Two hinging seats (224) on the same bidirectional screw rod (223) and adjacent main clamping beams (31) are connected with double-head telescopic pull rods (32), two telescopic ends of each double-head telescopic pull rod (32) are respectively hinged on the hinging seat (224) and the main clamping beam (31), and non-telescopic ends of each double-head telescopic pull rod (32) are horizontally rotatably arranged on the tool rack (1);

A gear (2231) is fixed on the bidirectional screw rod (223); the driving assembly (21) comprises a rack (212) which is horizontally driven and slidably installed on the tool rack (1), and a plurality of gears (2231) are meshed with the rack (212) together;

The double-end telescopic pull rod (32) comprises a central tube (321) and two sliding rods (322) which are arranged at two ends of the central tube (321) in a relative sliding fit manner; the tool rack (1) and the two main clamping beams (31) are horizontally and fixedly provided with serial shafts (33), and central pipes (321) in a plurality of double-head telescopic pull rods (32) connected with the same main clamping beam (31) are jointly and rotatably arranged on the corresponding serial shafts (33); one end of one sliding rod (322) is hinged on the hinging seat (224), and one end of the other sliding rod (322) is hinged on the main clamping beam (31).

2. The welding fixture of an automotive body according to claim 1, wherein: the roller frame (2222) is horizontally fixed with a plurality of guide rods (2224) which are slidably mounted on the sliding support (2221), clamping springs (2225) are sleeved on the guide rods (2224), and two ends of each clamping spring (2225) are respectively fixed on the sliding support (2221) and the roller frame (2222).

3. The welding fixture of an automotive body according to claim 1, wherein: the fixture frame (1) is provided with a plurality of bearing plates (13) which are distributed alternately with a plurality of beam positioning mechanisms (22).

4. The welding fixture of an automotive body according to claim 1, wherein: the end clamp assembly (34) comprises an end clamp plate (342) which is installed on the main clamp beam (31) in a sliding mode along the length direction of the main clamp beam (31).