Automobile part machining and welding tooling

Abstract

The application relates to the technical field of welding tooling, and particularly discloses an automobile part machining and welding tooling which comprises a tooling base and hydraulic clamping arms, further comprises a plurality of positioning pins, and a fitting assembly is composed of two detachable upper and lower parts; a temperature control assembly is connected with the fitting assembly; the automobile part machining and welding tooling adopts one-to-one corresponding dot matrix telescopic supporting columns for the fitting assembly, so as to adapt to the arc-shaped surface of a workpiece and stamping tolerance, the tooling transformation cost is low, the upper and lower counter-pressure structure makes the force of the workpiece uniform, the temperature of the fitting area of the fitting assembly is detected through the set temperature control assembly, the clamping force between the fitting assembly and the workpiece is increased when the temperature of the workpiece in the supporting area of the fitting assembly is increased, and the warping deformation of the supporting surface of the workpiece is avoided.

Description

Technical Field

[0001] This invention relates to the field of welding tooling technology, specifically to a welding tooling for processing automotive parts. Background Technology

[0002] Automotive parts welding fixtures are specialized process equipment used to precisely position, reliably clamp, and prevent deformation of automotive parts during the welding process. They act like the "skeleton" and "positioner" of the parts, ensuring that each welded part is dimensionally consistent and accurately positioned.

[0003] When welding thin, complex-curved automotive parts such as body panels, workers place the stamped workpiece stably on multiple sets of vertical support brackets of the fixture, ensuring the lower surface of the workpiece initially aligns with the support positioning blocks. Then, using process holes or main positioning holes at both ends of the fixture, cylindrical pins and diamond pins restrict the workpiece's freedom of movement. Next, small parts such as mounting brackets, welding nuts, and wiring harness clips are inserted into their corresponding positioning slots / pins on the fixture, ensuring a tight fit between the welding surfaces of these small parts and the main workpiece. Afterward, the workpiece is manually fine-tuned to ensure its curved surface is completely aligned with all support positioning blocks, without warping or gaps. Finally, workers operate the fixture's control valves (foot valves or manual valve groups) to sequentially drive each set of pneumatic lever clamping mechanisms downward, pressing the main support points from above the workpiece. After clamping, each clamp is confirmed to be in place, ensuring no gaps between the workpiece and the positioning surfaces.

[0004] However, when welding long, curved automotive parts, relying solely on discrete vertical supports results in weak rigidity in the middle span area. The welding heat input easily induces wavy and angular deformation in the thin sheet metal, leading to slight workpiece deformation and affecting post-weld dimensional accuracy. This necessitates that after the operator releases the clamps and removes the workpiece, it must be transferred to an inspection station to check the critical dimensions and surfaces of the automotive part, confirming that the deformation is within the standard allowable range. Defective parts require rework, adding extra inspection and correction processes and slowing down the production cycle. Therefore, we propose a welding fixture for automotive parts processing. Summary of the Invention

[0005] The purpose of this invention is to provide a welding fixture for automotive parts processing, in order to solve the problem mentioned in the background art that welding heat input during welding can easily cause wavy deformation and angular deformation of thin plates, resulting in slight deformation of the workpiece, which in turn affects the dimensional and positional accuracy after welding. As a result, after the operator releases the clamps and removes the workpiece, it is necessary to transfer the workpiece to the inspection station to inspect the key dimensions and surfaces of the automotive parts, confirm whether the deformation is within the standard allowable range, and rework the unqualified automotive parts, which adds extra inspection and correction processes and slows down the production cycle.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a welding fixture for processing automotive parts, comprising a fixture base and a hydraulic clamping arm, the hydraulic clamping arm being mounted on the surface of the fixture base; and further comprising a plurality of locating pins, the plurality of locating pins being fixedly connected to the fixture base, the locating pins being inserted into corresponding locating holes on the workpiece; The bonding assembly consists of two detachable parts, upper and lower. The lower part of the bonding assembly is connected to the tooling base. After assembly, the bonding assembly clamps and bonds the upper and lower surfaces of the workpiece. The bonding assembly also adaptively adjusts according to the surface curvature of the workpiece when bonding with the workpiece surface. The temperature control component is connected to the bonding component. During workpiece welding, the temperature control component quickly conducts away local heat through the contact surface, and adjusts the clamping pressure of the bonding component on the workpiece in real time according to temperature changes.

[0007] The bonding component includes a lower support block and an upper clamping block. The lower support block is fixedly connected to the tooling base, and multiple bolts are fixedly connected to the surface of the lower support block. The upper clamping block is initially connected to the lower support block through a nut. The inner walls of the lower support block and the upper clamping block are respectively provided with abutment parts that conform to the shape of the workpiece surface.

[0008] The abutment component includes multiple limiting posts, which are distributed in a dot matrix pattern on the inner wall of the upper clamping block. The limiting posts are fixed to the inner wall of the upper clamping block. An air storage box is fixedly connected to the inner wall of the upper clamping block and communicates with the multiple limiting posts. A support post is slidably connected to the inner wall of the limiting posts. The end of the support post near the workpiece is made of silicon nitride ceramic. A piston plate is slidably and sealed to the inner wall of the limiting post. The piston plate is fixedly connected to the support post. A return spring is sleeved on the outside of the support post. The two ends of the return spring are fixed to the piston plate and the inner wall of the limiting post, respectively. A detection element is provided on the inner wall of the air storage box to detect the pressure between the support post and the workpiece surface. An adjustment element is provided on the outside of the air storage box to adjust the pressure between the support post and the workpiece surface.

[0009] The detection component includes a detection cylinder that communicates with the gas storage box. A piston plate 2 is slidably and sealingly connected to the inner wall of the detection cylinder. A trigger rod is fixedly connected to one end of the piston plate 2 away from the gas storage box. The trigger rod is slidably connected to the inner wall of the detection cylinder. A reset spring 2 is sleeved on the outside of the trigger rod. The two ends of the reset spring 2 are fixed to the piston plate 2 and the inner wall of the gas storage box, respectively.

[0010] The adjusting components include an air compressor and an air tank mounted on the surface of the tooling base. Multiple air supply pipes are connected to the outside of the air tank. A rotary joint is fixedly connected to the end of the air supply pipe away from the air tank. The rotary joint is threadedly connected to the air tank. A solenoid valve is fixedly connected to the end of the air supply pipe near the air tank. Limit switches one and three are installed on the inner wall of the detection cylinder. Limit switches one and three are electrically connected to the solenoid valve. Limit switch one controls the solenoid valve to close. A pressure relief hole is opened on the inner wall of the detection cylinder.

[0011] The distance between limit switch one and trigger rod is the same as the distance between pressure relief hole and piston plate two. When the trigger rod presses limit switch one, the gas in the gas storage box is discharged through pressure relief hole.

[0012] The temperature control component includes a water tank mounted on the surface of the tooling base. A water pump is fixedly connected to the top of the water tank, and the output end of the water pump is connected to a main water supply pipe. A distribution box is fixedly connected to the top of the water tank, and the main water supply pipe is connected to the distribution box. Multiple branch water supply pipes are connected to the top of the distribution box. Cavities are formed in the inner walls of the lower support block and the upper clamping block, and multiple limiting posts are arrayed inside the cavities. A rotary joint II is fixedly connected to the end of the branch water supply pipe away from the distribution box. Multiple rotary joint IIs are threadedly connected to the corresponding lower support block and upper clamping block. The cavities and the branch water supply pipes are connected to the distribution box. The pipes are connected, and a return pipe is connected to the top of the water tank. A rotary joint three is fixedly connected to the end of the return pipe away from the water tank. Multiple rotary joint three are threadedly connected to the corresponding lower support block and upper clamping block. The cavity is connected to the return pipe. Multiple temperature measuring elements are provided between the return pipe and the water tank to detect the temperature of the water flow in the return pipe. Multiple temperature measuring elements correspond to multiple return pipes. A speed regulating element is provided between the distribution box and the water supply branch pipe to adjust the flow rate of cooling water entering the cavity according to the change of return water temperature. Multiple speed regulating elements are provided, and multiple speed regulating elements correspond to multiple temperature measuring elements.

[0013] The temperature measuring component includes a connecting box, one end of which is connected to the water tank and the other end of which is connected to the return pipe. A heat-conducting aluminum sheet is fixedly connected to the inner wall of the connecting box, and a temperature measuring box is fixedly connected to the outer side of the connecting box. A rubber sealing membrane is fixedly connected to the inner wall of the temperature measuring box, and paraffin wax is filled between the rubber sealing membrane and the temperature measuring box. One end of the heat-conducting aluminum sheet is located inside the connecting box, and the other end of the heat-conducting aluminum sheet passes through the connecting box and the temperature measuring box and is inserted into the paraffin wax. A push rod is fixedly connected to the end of the rubber sealing membrane away from the paraffin wax. A compression spring is fixedly connected between the push rod and the inner wall of the temperature measuring box. A limit switch two is installed on the inner wall of the temperature measuring box, and the limit switch two corresponds to the position of the push rod. The limit switch two controls the opening of the solenoid valve. A sliding rheostat is installed on the inner wall of the temperature measuring box. The push rod is fixedly connected to the slider of the sliding rheostat, and the sliding rheostat is connected to the corresponding speed regulating component. When the temperature of the return water in the connecting box rises, the push rod moves the slider of the sliding rheostat, and the resistance of the sliding rheostat decreases.

[0014] The distribution box has a flow guide hole at the end near the water supply branch pipe. The speed regulating component includes a sealing plate that is slidably and sealingly connected to the inner wall of the flow guide hole. A movable frame is fixedly connected to the outer side of the sealing plate. The movable frame is slidably connected to the inner wall of the distribution box. A reset spring is fixedly connected between the movable frame and the distribution box. An electromagnet is installed on the inner wall of the distribution box. The electromagnet and the corresponding sliding rheostat are connected in series in the same circuit. An armature is fixedly connected to the end of the movable frame near the electromagnet.

[0015] The water tank is equipped with a variable frequency chiller, and multiple sliding rheostats are connected in series in the circuit of the variable frequency chiller.

[0016] This invention has at least the following beneficial effects: In use, the bonding component employs a one-to-one correspondence dot matrix telescopic support column, thereby adapting to the workpiece's curved surface and stamping tolerances. This results in low tooling changeover costs. The upper and lower pressing structure ensures uniform stress on the workpiece, avoiding additional bending stress caused by unilateral clamping. A temperature control component monitors the temperature of the bonding area of ​​the bonding component. When the workpiece temperature in the support area of ​​the bonding component rises, the clamping force between the bonding component and the workpiece increases, preventing warping and deformation of the workpiece's support surface. When the temperature in the support area exceeds a preset threshold, the clamping force stops increasing, maintaining a safe and constant constraint pressure. This prevents indentations on the surface of automotive parts sheet metal, improves the welding flatness of automotive parts, reduces rework rates, and accelerates production cycle time. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of the present invention; Figure 2 for Figure 1 Enlarged diagram of area A in the middle; Figure 3 for Figure 1 Enlarged diagram of area B in the middle; Figure 4 This is a schematic diagram of the bonding component structure of the present invention; Figure 5 This is a schematic diagram of the internal structure of the clamping block in this invention; Figure 6 This is a schematic diagram of the side cross-sectional structure of the clamping block of the present invention; Figure 7 for Figure 6 Enlarged diagram of area C; Figure 8 This is a schematic diagram of the internal structure of the gas storage box of the present invention; Figure 9 for Figure 8 Enlarged diagram of area D in the middle; Figure 10 This is a schematic diagram of the temperature measuring element structure of the present invention; Figure 11 This is a side cross-sectional view of the temperature measuring element of the present invention; Figure 12 for Figure 11 Enlarged schematic diagram of area E in the middle.

[0018] In the diagram: 1. Tooling base; 2. Hydraulic clamping arm; 3. Positioning pin; 4. Fitting assembly; 40. Lower support block; 41. Upper clamping block; 42. Bolt; 43. Abutment part; 44. Limiting post; 45. Air storage box; 46. Support column; 47. Piston plate one; 48. Return spring one; 49. Detection piece; 410. Adjusting piece; 411. Detection cylinder; 412. Piston plate two; 413. Trigger rod; 414. Return spring two; 415. Air compressor; 416. Air storage tank; 417. Air delivery pipe; 418. Rotary joint one; 419. Solenoid valve; 420. Limit switch one; 421. Limit switch three; 422. Pressure relief hole; 5. Temperature control components; 50. Water tank; 51. Water pump; 52. Main water supply pipe; 53. Distribution box; 54. Branch water supply pipe; 55. Cavity; 56. Rotary joint II; 57. Return pipe; 58. Rotary joint III; 59. Temperature measuring element; 510. Speed ​​regulating element; 511. Connecting box; 512. Thermally conductive aluminum sheet; 513. Temperature measuring box; 514. Rubber sealing membrane; 515. Push rod; 516. Compression spring; 517. Limit switch II; 518. Sliding rheostat; 519. Flow guide hole; 520. Sealing plate; 521. Moving frame; 522. Return spring III; 523. Electromagnet; 524. Armature; 525. Paraffin wax; 6. Variable frequency chiller. Detailed Implementation

[0019] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] Example 1 Please see Figures 1 to 12 This invention provides a technical solution: a welding fixture for processing automotive parts, including a fixture base 1 and a hydraulic clamping arm 2, the hydraulic clamping arm 2 being mounted on the surface of the fixture base 1; it also includes multiple positioning pins 3, which are fixedly connected to the fixture base 1 and inserted into corresponding positioning holes on the workpiece; a bonding component 4, which consists of two detachable upper and lower parts, the lower part of which is connected to the fixture base 1, and the bonding component 4, after assembly, bonding and clamping the upper and lower surfaces of the workpiece, and adaptively adjusting according to the surface curvature of the workpiece when bonding with the workpiece surface; and a temperature control component 5, which is connected to the bonding component 4, and rapidly conducts away local heat through the contact surface during workpiece welding, and adjusts the clamping pressure of the bonding component 4 on the workpiece in real time according to temperature changes.

[0021] When in use, the stamped workpiece to be welded is placed stably on the tooling base 1, and the main positioning holes and process holes at both ends of the workpiece are fitted into the positioning pins 3 to complete the plane degree of freedom restriction. The workpiece is positioned by the bonding component 4 and the hydraulic clamping arm 2. After the workpiece is clamped, the welding program is started for welding. The temperature control component 5 actively dissipates heat from the workpiece support surface. When the workpiece temperature in the support area of ​​the bonding component 4 rises, the clamping force between the bonding component 4 and the workpiece increases to prevent the support surface of the workpiece from warping and deforming. When the workpiece temperature in the support area exceeds the preset threshold, the clamping force no longer increases, maintaining a safe and constant constraint pressure, achieving active high-temperature protection, preventing indentations on the surface of automotive parts sheet metal, improving the welding flatness of automotive parts, reducing the rework rate, and accelerating the production cycle.

[0022] After welding, the bonding component 4 and the temperature control component 5 remain in operation. The bonding component 4 continues to clamp the workpiece, and the temperature control component 5 continues to remove residual heat. During the process of restoring the rigidity of the sheet material, the shrinkage deformation is continuously constrained to ensure the surface accuracy after cooling and shaping.

[0023] Once the workpiece has cooled to a safe temperature, release the bonding assembly 4 and loosen the hydraulic clamping arm 2. Remove the welded workpiece from the fixture and proceed to the next process to complete a single welding cycle.

[0024] The bonding component 4 includes a lower support block 40 and an upper clamping block 41. The lower support block 40 is fixedly connected to the tooling base 1. Multiple bolts 42 are fixedly connected to the surface of the lower support block 40. The upper clamping block 41 is initially connected to the lower support block 40 through nuts. The inner walls of the lower support block 40 and the upper clamping block 41 are respectively provided with abutment parts 43 that conform to the shape of the workpiece surface.

[0025] The abutment part 43 of the lower support block 40 has the same structure as the upper clamping block 41 and is arranged symmetrically.

[0026] The abutment member 43 includes multiple limiting posts 44, which are distributed in a dot matrix pattern on the inner wall of the upper clamping block 41. The limiting posts 44 are fixed to the inner wall of the upper clamping block 41. An air storage box 45 is fixedly connected to the inner wall of the upper clamping block 41, and the air storage box 45 communicates with the multiple limiting posts 44. A support post 46 is slidably connected to the inner wall of the limiting posts 44. The end of the support post 46 near the workpiece is made of silicon nitride ceramic, which is high temperature resistant, insulating, and prevents welding slag. A piston plate is slidably and sealingly connected to the inner wall of the limiting posts 44. Piston plate 47 is fixedly connected to support column 46. A return spring 48 is sleeved on the outside of support column 46. The two ends of return spring 48 are fixed to piston plate 47 and inner wall of limit column 44 respectively. Under normal conditions, return spring 48 pulls support column 46 back to the retracted position. The inner wall of air storage box 45 is provided with a detection element 49 for detecting the pressure between support column 46 and workpiece surface. The outside of air storage box 45 is provided with an adjustment element 410 for adjusting the pressure between support column 46 and workpiece surface.

[0027] In use, the upper clamping block 41 is fastened, and the upper clamping block 41 and the lower support block 40 are initially locked and fixed by bolts 42 and nuts. Air is injected into the air storage box 45 through the adjusting component 410. The air storage box 45 has a uniform air chamber inside. After compressed air is introduced, all support columns 46 can be driven to extend outward synchronously. As the air pressure in the air storage box 45 increases, the gas in the air storage box 45 pushes the piston plate 47 to slide on the inner wall of the limiting column 44. The piston plate 47 pushes the support column 46 closer to the workpiece surface. Since the workpiece surface is arc-shaped... When the support column 46 at different positions contacts the workpiece surface, the reaction force on the support column 46 is different, and the return spring 48 is compressed to different compression amounts. The extension length of each support column 46 automatically matches the curvature of the workpiece surface to achieve adaptive fit. The upper and lower pressure structure makes the workpiece subjected to uniform force and avoids the additional bending stress caused by unilateral clamping. As the adjusting component 410 fills the air storage box 45 with air, the detection component 49 detects the air pressure in the air storage box 45 in real time, and together they achieve constant pressure clamping and dynamic pressure adjustment.

[0028] The detection component 49 includes a detection cylinder 411 that communicates with the gas storage box 45. A piston plate 412 is slidably and sealingly connected to the inner wall of the detection cylinder 411. A trigger rod 413 is fixedly connected to one end of the piston plate 412 away from the gas storage box 45. The trigger rod 413 is slidably connected to the inner wall of the detection cylinder 411. A reset spring 414 is sleeved on the outer side of the trigger rod 413. The two ends of the reset spring 414 are fixed to the piston plate 412 and the inner wall of the gas storage box 45, respectively.

[0029] The adjusting component 410 includes an air compressor 415 and an air tank 416 mounted on the surface of the tooling base 1. Multiple air supply pipes 417 are connected to the outside of the air tank 416. A rotary joint 418 is fixedly connected to the end of the air supply pipe 417 away from the air tank 416. The rotary joint 418 is threadedly connected to the air storage box 45 to facilitate the disassembly and replacement of the upper clamping block 41. A solenoid valve 419 is fixedly connected to the end of the air supply pipe 417 near the air tank 416. Limit switches 420 and 421 are installed on the inner wall of the detection cylinder 411. Limit switches 420 and 421 are electrically connected to the solenoid valve 419. Limit switches 420 and 421 control the solenoid valve 419 to close. A pressure relief hole 422 is opened on the inner wall of the detection cylinder 411, which is connected to the outside atmosphere.

[0030] The distance between limit switch 420 and trigger rod 413 is the same as the distance between pressure relief hole 422 and piston plate 412. When the air pressure in the air storage box 45 reaches the set value, when trigger rod 413 presses limit switch 420, the gas in the air storage box 45 is discharged through pressure relief hole 422, maintaining constant air chamber pressure.

[0031] The detection element 49 is used to detect the air pressure value inside the air storage box 45, indirectly reflecting the pressure of the support column 46 on the workpiece. When the air pressure inside the air storage box 45 pushes the piston plate 412 to move, the piston plate 412 pushes the trigger rod 413 to move synchronously. The displacement of the trigger rod 413 is proportional to the air pressure. By detecting whether the trigger rod 413 has reached the preset position through the limit switch 420, it can be determined whether the air pressure has reached the set value, thus realizing the pressure monitoring function.

[0032] When in use, start the air compressor 415. Compressed air is stored in the air tank 416. Open the solenoid valve 419 of the corresponding workstation. Compressed air enters the air storage box 45 through the air supply pipe 417 and rotary joint 418. The air pressure pushes the piston plate 47 in each limit column 44 to extend outward, driving the support column 46 to push against the workpiece surface. Since the workpiece surface is an arc-shaped curved surface, the support column 46 at different positions experiences different reaction forces, which compress the reset spring 48 to different heights, automatically adapting to the curvature of the workpiece surface and achieving uniform contact at all points. When the trigger rod 413 presses the limit switch 421, the solenoid valve 419 closes, so that the pressure of the support column 46 on the workpiece reaches the normal temperature pressure value.

[0033] When welding the workpiece, the temperature of the workpiece between the lower support block 40 and the upper clamping block 41 rises. At this time, in order to prevent the workpiece from warping, the temperature control component 5 controls the solenoid valve 419 to open. As the air pressure in the air storage box 45 continues to rise, the piston plate 412 in the detection cylinder 411 overcomes the elastic force of the reset spring 414 and drives the trigger rod 413 to move outward, which increases the pressure of the support column 46 on the workpiece. The multiple support columns 46 distributed in an array form a pressing surface to suppress the deformation of the workpiece. When the temperature of the workpiece in the support area exceeds the preset threshold, that is, when the temperature of the workpiece in the support area exceeds 400℃, the low carbon steel enters a significant softening range, and its mechanical properties drop precipitously. At this time, the air pressure in the air storage box 45 reaches the set rated value, and the trigger rod 413 presses the trigger limit switch 420. At the same time, the piston plate 412 moves to the outside of the pressure relief hole 422, and the excess gas in the air storage box 45 overflows through the pressure relief hole 422. At this time, the solenoid valve 419 receives the signal from the limit switch 420 and closes, stopping the air supply. The air storage box 45 maintains a constant pressure, preventing the softened plate from being pressed into plastic indentations, thus achieving active high-temperature protection.

[0034] Temperature control assembly 5 includes a water tank 50 mounted on the surface of tooling base 1. A water pump 51 is fixedly connected to the top of the water tank 50. The output end of the water pump 51 is connected to a main water supply pipe 52. A distribution box 53 is fixedly connected to the top of the water tank 50. The main water supply pipe 52 is connected to the distribution box 53. Multiple water supply branch pipes 54 are connected to the top of the distribution box 53. Cavities 55 are respectively opened in the inner walls of the lower support block 40 and the upper clamping block 41. Multiple limiting posts 44 are arrayed inside the cavities 55. A rotary joint 56 is fixedly connected to the end of the water supply branch pipe 54 away from the distribution box 53. Multiple rotary joints 56 are respectively threaded to the corresponding lower support block 40 and upper clamping block 41. The cavities 55 and the water supply branch pipes 54 are connected to each other. The water tank 50 is connected to a return pipe 57 at the top. A rotary joint 3 58 is fixedly connected to the end of the return pipe 57 away from the water tank 50. Multiple rotary joints 3 58 are threadedly connected to the corresponding lower support block 40 and upper clamping block 41. The cavity 55 is connected to the return pipe 57. Multiple temperature measuring elements 59 are provided between the return pipe 57 and the water tank 50 to detect the temperature of the water flow in the return pipe 57. Multiple temperature measuring elements 59 correspond one-to-one with multiple return pipes 57. A speed regulating element 510 is provided between the distribution box 53 and the water supply branch pipe 54 to adjust the flow rate of cooling water entering the cavity 55 according to the change of return water temperature. Multiple speed regulating elements 510 are provided, and multiple speed regulating elements 510 correspond one-to-one with multiple temperature measuring elements 59.

[0035] During use, cooling water is pressurized from water tank 50 by water pump 51 and enters main water supply pipe 52, then flows into distribution box 53, and enters the cooling cavity 55 of lower support block 40 and upper clamping block 41 through each guide hole 519, water supply branch pipe 54, and rotary joint 2 56 respectively. The cooling water quickly absorbs welding heat through the wall of cavity 55 and limit post 44, actively dissipating heat from the workpiece support area. The heated water flows back to water tank 50 through return pipe 57 and rotary joint 3 58, forming a closed loop. Each set of return pipe 57 is equipped with a set of temperature measuring elements 59. The temperature of the return water is detected by the temperature measuring elements 59, and the temperature of the workpiece support surface is determined based on the temperature of the return water. The speed regulating element 510 adjusts the flow rate of cooling water into cavity 55 according to the detection results of temperature measuring elements 59, thereby improving the cooling effect on the workpiece.

[0036] Temperature measuring element 59 includes a connecting box 511, one end of which is connected to the water tank 50, and the other end of which is connected to the return pipe 57. A heat-conducting aluminum sheet 512 is fixedly connected to the inner wall of the connecting box 511 for rapid heat conduction of the water flow. A temperature measuring box 513 is fixedly connected to the outer side of the connecting box 511. A rubber sealing film 514 is fixedly connected to the inner wall of the temperature measuring box 513. Paraffin wax 525 is filled between the rubber sealing film 514 and the temperature measuring box 513. One end of the heat-conducting aluminum sheet 512 is located inside the connecting box 511, and the other end of the heat-conducting aluminum sheet 512 passes through the connecting box 511 and the temperature measuring box 513 and is inserted into the paraffin wax 525. Inside 25, a push rod 515 is fixedly connected to the end of the rubber sealing film 514 away from the paraffin 525. A compression spring 516 is fixedly connected between the push rod 515 and the temperature measuring box 513. The push rod 515 is slidably connected to the inner wall of the temperature measuring box 513. A limit switch 517 is installed on the inner wall of the temperature measuring box 513. The limit switch 517 corresponds to the position of the push rod 515. The limit switch 517 controls the solenoid valve 419 to open. A sliding rheostat 518 is installed on the inner wall of the temperature measuring box 513. The push rod 515 is fixedly connected to the slider of the sliding rheostat 518. The sliding rheostat 518 is connected to the corresponding speed regulating component 510.

[0037] The phase transition temperature and volume expansion coefficient of the paraffin 525 filled in the temperature measuring box 513 are selected by the staff according to the actual situation.

[0038] When the temperature of the return water in the connecting box 511 rises, the paraffin wax 525 melts and expands, pushing the rubber sealing membrane 514 to bulge. The rubber sealing membrane 514 drives the push rod 515 to move, and the push rod 515 drives the slider of the sliding rheostat 518 to move. The resistance of the sliding rheostat 518 decreases, and the speed regulating component 510 controls the increase of the cooling water flow rate.

[0039] When the movement of push rod 515 triggers limit switch 517, the temperature of the return water is high, the paraffin wax 525 is completely melted, and the temperature of the workpiece support surface is high. In order to prevent the workpiece from warping due to the temperature rise, limit switch 517 controls the corresponding solenoid valve 419 to open, and compressed air continues to enter the air storage box 45, thereby increasing the squeezing force of the support column 46 on the workpiece, restraining the workpiece from warping, and improving the flatness of the workpiece surface.

[0040] A guide hole 519 is provided at one end of the distribution box 53 near the water supply branch pipe 54. The speed regulating component 510 includes a sealing plate 520 that is slidably and sealingly connected to the inner wall of the guide hole 519. A movable frame 521 is fixedly connected to the outside of the sealing plate 520. The movable frame 521 is slidably connected to the inner wall of the distribution box 53. A return spring 522 is fixedly connected between the movable frame 521 and the distribution box 53. An electromagnet 523 is installed on the inner wall of the distribution box 53. The electromagnet 523 and the corresponding sliding rheostat 518 are connected in series in the same circuit. An armature 524 is fixedly connected at one end of the movable frame 521 near the electromagnet 523.

[0041] When the return water temperature rises, the paraffin wax 525 melts and expands in volume, pushing the rubber sealing membrane 514 to bulge outward. This causes the push rod 515 to slide outward against the spring force of the compression spring 516. The push rod 515 then moves the slider of the sliding rheostat 518, causing the resistance of the sliding rheostat 518 to decrease. The decrease in resistance increases the circuit current of the electromagnet 523 connected in series, strengthening the attraction of the electromagnet 523. This attracts the armature 524, causing the moving frame 521 and the sealing plate 520 to move outward. This increases the cross-sectional area of ​​the guide hole 519, increasing the cooling water flow rate and enhancing heat dissipation in this area. When the return water temperature decreases, the paraffin wax 525 solidifies and shrinks, the push rod 515 resets under the action of the compression spring 516, the resistance of the sliding rheostat 518 increases, the attraction of the electromagnet 523 weakens, and the sealing plate 520 resets to reduce the flow rate, thereby realizing automatic matching of the flow rate with the local heat load.

[0042] Example 2 In this second embodiment, the other structures remain unchanged. The difference from the first embodiment is that a variable frequency chiller 6 is installed on the outside of the water tank 50 to cool the coolant in the water tank 50. Multiple sliding rheostats 518 are connected in series in the circuit where the variable frequency chiller 6 is located.

[0043] When the overall welding heat load increases and the temperature of multiple sets of return water rises synchronously, the total resistance continues to decrease. After receiving the signal, the variable frequency chiller 6 increases the operating frequency, the cooling power increases, the cooling rate of the coolant in the water tank 50 accelerates, and the outlet water temperature is kept stable. During production breaks and when the heat load decreases, the chiller automatically reduces the frequency to save energy.

[0044] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0045] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A welding fixture for machining automotive parts, comprising: Tooling base and hydraulic clamping arm, wherein the hydraulic clamping arm is mounted on the surface of the tooling base; Its characteristic is that it also includes a plurality of positioning pins, which are fixedly connected to the tooling base, and the positioning pins are inserted into corresponding positioning holes on the workpiece; The bonding assembly consists of two detachable upper and lower parts. The lower part of the bonding assembly is connected to the tooling base. After assembly, the bonding assembly clamps and bonds the upper and lower surfaces of the workpiece. The bonding assembly also adaptively adjusts according to the surface curvature of the workpiece when bonding with the workpiece surface. A temperature control component is connected to a bonding component. During workpiece welding, the temperature control component quickly conducts away local heat through the contact surface, and adjusts the clamping pressure of the bonding component on the workpiece in real time according to temperature changes.

2. The welding fixture for processing automotive parts according to claim 1, characterized in that: The bonding assembly includes a lower support block and an upper clamping block. The lower support block is fixedly connected to the tooling base. Multiple bolts are fixedly connected to the surface of the lower support block. The upper clamping block is initially connected to the lower support block by a nut. The inner walls of the lower support block and the upper clamping block are respectively provided with abutment members that conform to the shape of the workpiece surface.

3. The welding fixture for processing automotive parts according to claim 2, characterized in that: The abutment component includes multiple limiting posts, which are distributed in a dot matrix pattern on the inner wall of the upper clamping block. The limiting posts are fixed to the inner wall of the upper clamping block. An air storage box is fixedly connected to the inner wall of the upper clamping block, and the air storage box communicates with the multiple limiting posts. A support post is slidably connected to the inner wall of the limiting posts. The end of the support post near the workpiece is made of silicon nitride ceramic. A piston plate is slidably and sealingly connected to the inner wall of the limiting post. The piston plate is fixedly connected to the support post. A return spring is sleeved on the outside of the support post. The two ends of the return spring are fixed to the piston plate and the inner wall of the limiting post, respectively. A detection element for detecting the pressure between the support post and the workpiece surface is provided on the inner wall of the air storage box. An adjustment element for adjusting the pressure between the support post and the workpiece surface is provided on the outside of the air storage box.

4. The automotive parts processing and welding fixture according to claim 3, characterized in that: The detection component includes a detection cylinder that communicates with the gas storage box. A piston plate two is slidably and sealingly connected to the inner wall of the detection cylinder. A trigger rod is fixedly connected to one end of the piston plate two away from the gas storage box. The trigger rod is slidably connected to the inner wall of the detection cylinder. A reset spring two is sleeved on the outer side of the trigger rod. The two ends of the reset spring two are fixed to the piston plate two and the inner wall of the gas storage box, respectively.

5. The automotive parts processing and welding fixture according to claim 4, characterized in that: The adjusting component includes an air compressor and an air tank mounted on the surface of the tooling base. Multiple air supply pipes are connected to the outside of the air tank. A rotary joint is fixedly connected to the end of the air supply pipe away from the air tank. The rotary joint is threadedly connected to the air tank. A solenoid valve is fixedly connected to the end of the air supply pipe near the air tank. Limit switches one and three are installed on the inner wall of the detection cylinder. Limit switches one and three are electrically connected to the solenoid valve. Limit switch one controls the solenoid valve to close. A pressure relief hole is opened on the inner wall of the detection cylinder.

6. The welding fixture for processing automotive parts according to claim 5, characterized in that: The distance between the limit switch and the trigger rod is the same as the distance between the pressure relief hole and the piston plate. When the trigger rod presses the limit switch, the gas in the gas storage box is discharged through the pressure relief hole.

7. The welding fixture for processing automotive parts according to claim 5, characterized in that: The temperature control assembly includes a water tank mounted on the surface of the tooling base. A water pump is fixedly connected to the top of the water tank, and the output end of the water pump is connected to a main water supply pipe. A distribution box is fixedly connected to the top of the water tank, and the main water supply pipe is connected to the distribution box. Multiple branch water supply pipes are connected to the top of the distribution box. Cavities are formed in the inner walls of the lower support block and the upper clamping block, and multiple limiting posts are arrayed inside the cavities. A rotary joint II is fixedly connected to the end of the branch water supply pipe away from the distribution box. Multiple rotary joint IIs are threadedly connected to the corresponding lower support block and upper clamping block. The cavities are connected to the water supply pipes. The branch pipe is connected, and the top of the water tank is connected to a return pipe. A rotary joint three is fixedly connected to the end of the return pipe away from the water tank. Multiple rotary joint three are respectively threadedly connected to the corresponding lower support block and upper clamping block. The cavity is connected to the return pipe. Multiple temperature measuring elements for detecting the water temperature in the return pipe are provided between the return pipe and the water tank. Each of the multiple temperature measuring elements corresponds to a multiple return pipe. A speed regulating element for adjusting the flow rate of cooling water into the cavity according to the change of return water temperature is provided between the distribution box and the water supply branch pipe. Multiple speed regulating elements are provided, and each of the multiple speed regulating elements corresponds to a multiple temperature measuring element.

8. The welding fixture for processing automotive parts according to claim 7, characterized in that: The temperature measuring device includes a connecting box, one end of which is connected to a water tank and the other end of which is connected to a return pipe. A heat-conducting aluminum sheet is fixedly connected to the inner wall of the connecting box, and a temperature measuring box is fixedly connected to the outer side of the connecting box. A rubber sealing membrane is fixedly connected to the inner wall of the temperature measuring box, and paraffin wax is filled between the rubber sealing membrane and the temperature measuring box. One end of the heat-conducting aluminum sheet is located inside the connecting box, and the other end of the heat-conducting aluminum sheet passes through the connecting box and the temperature measuring box and is inserted into the paraffin wax. A push rod is fixedly connected to the end of the rubber sealing membrane away from the paraffin wax. A compression spring is fixedly connected between the push rod and the temperature measuring box. The push rod is slidably connected to the inner wall of the temperature measuring box. A second limit switch is installed on the inner wall of the temperature measuring box, and the second limit switch corresponds to the position of the push rod. The second limit switch controls the opening of the solenoid valve. A sliding rheostat is installed on the inner wall of the temperature measuring box, and the push rod is fixedly connected to the slider of the sliding rheostat. The sliding rheostat is connected to a corresponding speed regulating component. When the temperature of the return water in the connecting box rises, the push rod drives the slider of the sliding rheostat to move, and the resistance of the sliding rheostat decreases.

9. The welding fixture for processing automotive parts according to claim 8, characterized in that: The distribution box has a flow guide hole at one end near the water supply branch pipe. The speed regulating component includes a sealing plate that is slidably and sealingly connected to the inner wall of the flow guide hole. A movable frame is fixedly connected to the outer side of the sealing plate. The movable frame is slidably connected to the inner wall of the distribution box. A return spring is fixedly connected between the movable frame and the distribution box. An electromagnet is installed on the inner wall of the distribution box. The electromagnet and a corresponding sliding rheostat are connected in series in the same circuit. An armature is fixedly connected to one end of the movable frame near the electromagnet.

10. The welding fixture for processing automotive parts according to claim 8, characterized in that: A variable frequency chiller is installed on the outside of the water tank, and multiple sliding rheostats are connected in series in the circuit of the variable frequency chiller.

Images