A metal plate welding device for security door production

Abstract

The present application relates to the technical field of safety door production, and particularly relates to a metal plate welding device for safety door production, which comprises a rack, a mounting box, a mounting frame, vertical electric guide rails and a lifting plate, the top of the rack is connected with the mounting box, the top of the mounting box is connected with two mounting frames, two vertical electric guide rails are installed on the top of the mounting box, the vertical electric guide rails are connected with the mounting frames, and the sliding blocks of the two vertical electric guide rails are connected with the lifting plate. The first laser welding head is used to weld the gap on the top of the door frame, the second laser welding head is used to weld the gap inside the door frame, the third laser welding head is used to weld the gap outside the door frame, the rack can drive the gear to rotate, thereby driving the door frame to rotate, the door frame is automatically turned over, manual intervention is reduced, the workload of the staff is reduced, and the production efficiency is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of safety door production, and particularly relates to a metal plate welding device for safety door production. BACKGROUND

[0002] With the continuous improvement of building safety standards, the market demand for high-quality and high-performance safety doors is increasing, and the safety door is composed of a door frame and a door plate, and the door frame is composed of four metal plates which are connected through welding.

[0003] In the production of safety doors, the four metal plates are generally placed on a bracket and arranged into a door frame shape, then the door frame is fixed through a fixing piece, and a laser welding head is driven by a mechanical arm to move, so that the laser welding head welds the gaps of the door frame. The door frame is placed on the bracket, and the bottom of the door frame is in contact with the bracket, so the laser welding head can only weld the gaps at the top, outside and inside of the door frame. The door frame needs to be turned over to weld the gaps at the bottom of the door frame. The metal plate is relatively heavy, and manual turning over is difficult, which increases the workload of the workers and affects the production efficiency. SUMMARY

[0004] In order to overcome the shortcomings that the metal plate is relatively heavy, manual turning over is difficult, the workload of the workers is large, and the production efficiency is affected, the present application provides a metal plate welding device for safety door production.

[0005] The metal plate welding device for safety door production comprises a rack, a mounting box, mounting frames, vertical electric guide rails, a lifting plate, connecting plates, inclined electric guide rails, first laser welding heads, connecting blocks, first electric push rods, second laser welding heads, second electric push rods, third laser welding heads, rotating shafts, a placing plate, a turnover mechanism and a limiting mechanism.

[0006] Further, the turnover mechanism comprises two L-shaped plates, two racks and two gears, the bottom of the lifting plate is connected with the two L-shaped plates, the L-shaped plates are connected with the racks, the rotating shafts are connected with the gears through one-way clutches, and the racks are engaged with the gears during upward movement.

[0007] Further, the limiting mechanism comprises third electric push rods, first limiting plates, a mounting plate, fourth electric push rods, a moving plate, second limiting plates and fifth electric push rods, the top of the placing plate is connected with the two third electric push rods, the first limiting plates are connected with the extension rods of the two third electric push rods on the left side, the first limiting plates are also connected with the extension rods of the two third electric push rods on the right side, the first limiting plates are used for limiting the door frame, the upper portions of the two first limiting plates are provided with supporting portions for supporting the door frame, the bottom of the placing plate is connected with the mounting plate, the mounting plate is connected with the fourth electric push rods, the extension rods of the fourth electric push rods are connected with the moving plate, the moving plate is slidably connected with the second limiting plates, the bottom of the moving plate is connected with the two fifth electric push rods, the extension rods of the fifth electric push rods are connected with the second limiting plates, and the extension rods of the fifth electric push rods can drive the two second limiting plates to move towards each other, so that the second limiting plates limit the door frame.

[0008] Further, the support mechanism is further included, and the support mechanism comprises a guide frame, an insertion plate, a spring, an inclined plate and a pressing rod, guide frames are connected to the left and right sides of the installation box, the insertion plates are slidably connected into the guide frames, the springs are connected between the insertion plates and the guide frames, the inclined plates are connected to the insertion plates, the pressing rods are connected to the inclined plates, the insertion slots are formed in the left and right sides of the placement plate, and the pressing rods are used for pressing the inclined plates so that the insertion plates are inserted into the insertion slots and the placement plate is supported.

[0009] Further, the air injection mechanism is further included, and the air injection mechanism comprises an air outlet pipe, a spray head and an air guide pipe, two air outlet pipes are connected to the connecting plate, the spray heads for spraying carbon dioxide to the welding position of the door frame are connected to the air outlet pipes, and the air guide pipes are connected to the upper ends of the two air outlet pipes on the same connecting plate.

[0010] Further, the unloading mechanism is further included, and the unloading mechanism comprises a pneumatic cylinder and a pushing plate, the pneumatic cylinder is connected to the top of the installation box, and the pushing plate is connected to the telescopic rod of the pneumatic cylinder.

[0011] Further, the guide sleeves are connected to the vertical electric guide rails and used for guiding the U-shaped plates, the U-shaped plates are located in the guide sleeves, and the U-shaped plates and the guide sleeves are slidably connected.

[0012] Further, the notches are arranged at the four corners of the placement plate.

[0013] Further, the containing grooves for containing the second limiting plates are arranged on the front and rear sides of the placement plate.

[0014] The application has the following advantages: 1. The first laser welding head can weld the gap at the top of the door frame, the second laser welding head can weld the gap inside the door frame, the third laser welding head can weld the gap outside the door frame, the rack can drive the gear to rotate, thereby driving the door frame to rotate, automatically turning the door frame, reducing manual intervention, reducing the workload of the staff and improving the production efficiency.

[0015] 2. The insertion plates can support the placement plate, the stability of the placement plate is improved, when the U-shaped plates move upwards, the pressing rods move upwards, the insertion plates are moved out of the insertion slots, the placement plate is loosened, and the placement plate can rotate normally.

[0016] 3. The spray heads can spray carbon dioxide to the welding position of the door frame, promote the metal evaporation in the welding process and improve the welding stability.

[0017] 4. The telescopic rod of the pneumatic cylinder can drive the pushing plate to move forward, the pushing plate can push out the door frame after welding, and the staff can unload the door frame conveniently. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1A perspective view of the present application is shown.

[0019] Figure 2 A perspective view of the present application is shown.

[0020] Figure 3 A perspective view of the present application is shown.

[0021] Figure 4 A perspective view of the present application is shown.

[0022] Figure 5 A perspective view of the present application is shown.

[0023] Figure 6 A perspective view of the present application is shown.

[0024] Figure 7 A perspective view of the present application is shown.

[0025] Figure 8 A perspective view of the present application is shown.

[0026] Figure 9 A perspective view of the present application is shown.

[0027] Figure 10 A perspective view of the present application is shown.

[0028] Figure 11 A perspective view of the present application is shown.

[0029] Figure 12 A perspective view of the present application is shown.

[0030] Figure 13 A perspective view of the present application is shown.

[0031] Figure 14 A perspective view of the present application is shown.

[0032] Figure 15 A perspective view of the present application is shown.

[0033] Reference signs: 1-frame, 2-mounting box, 3-mounting frame, 4-vertical electric guide rail, 5-lifting plate, 6-connection plate, 7-inclined electric guide rail, 8-first laser welding head, 9-connection block, 10-first electric push rod, 11-second laser welding head, 12-second electric push rod, 13-third laser welding head, 131-rotation shaft, 132-placing plate, 14-plate, 15-rack, 16-gear, 17-third electric push rod, 18-first limiting plate, 181-supporting part, 19-mounting plate, 20-fourth electric push rod, 21-moving plate, 22-second limiting plate, 23-fifth electric push rod, 24-guiding frame, 25-inserting plate, 26-spring, 27-inclined plate, 28-pressing rod, 29-inserting slot, 30-outlet pipe, 31-nozzle, 32-air guide pipe, 33-air cylinder, 34-feeding plate, 35-guide sleeve. DETAILED DESCRIPTION

[0034] The application will be described in detail below with reference to the drawings.

[0035] Example 1: as Figures 1-10As shown, a kind of metal plate welding device for security door production, including rack 1, installation box 2, mounting bracket 3, vertical electric guide rail 4, lifting plate 5, connecting plate 6, inclined electric guide rail 7, first laser welding head 8, connecting block 9, first electric push rod 10, second laser welding head 11, second electric push rod 12, third laser welding head 13, pivot 131, placement plate 132, turnover mechanism and limiting mechanism, rack 1 top is connected by bolt with installation box 2, installation box 2 top left and right sides are all connected by bolt with mounting bracket 3, installation box 2 top left and right sides are all installed with vertical electric guide rail 4, vertical electric guide rail 4 top and mounting bracket 3 are connected, the sliding block between two vertical electric guide rails 4 is connected by bolt with lifting plate 5, lifting plate 5 bottom left and right sides are all connected by bolt with connecting plate 6, connecting plate 6 bottom front and back sides are all connected with inclined electric guide rail 7, the sliding block bottom of inclined electric guide rail 7 is all installed with first laser welding head 8, the upper portion of first laser welding head 8 is all connected with connecting block 9, the side of the bottom of four connecting blocks 9, which is close to each other, is all connected with first electric push rod 10, the lower end of the telescopic rod of first electric push rod 10 is all connected with second laser welding head 11, the side of the bottom of four connecting blocks 9, which is far away from each other, is all connected with second electric push rod 12, the lower end of the telescopic rod of second electric push rod 12 is all connected with third laser welding head 13, the left and right sides of the middle part in installation box 2 are all rotationally connected with pivot 131, the placement plate 132 is connected between two pivots 131, the lower end of second laser welding head 11 and the lower end of third laser welding head 13 are all higher than the lower end of first laser welding head 8, so that second laser welding head 11 and third laser welding head 13 will not touch placement plate 132 when first laser welding head 8 welds the gap at the bottom of door frame, the four corners of placement plate 132 are all provided with notches, so that the gap at the bottom of door frame can be exposed, so that first laser welding head 8 will not touch placement plate 132 when first laser welding head 8 welds the gap at the bottom of door frame, the inclination angle of inclined electric guide rail 7 is consistent with the inclination angle of the gap at the top of door frame, so that first laser welding head 8 can move along the gap at the top of door frame, so that first laser welding head 8 can smoothly weld the gap at the top of door frame, turnover mechanism is arranged on lifting plate 5 for turning over door frame, limiting mechanism is arranged on placement plate 132 for limiting door frame.

[0036] As Figure 5 and Figure 6 shown, turnover mechanism includes backplate 14, rack 15 and gear 16, lifting plate 5 bottom left and right sides are all connected by bolt with backplate 14, backplate 14 inner front side is all connected with rack 15, pivot 131 is all connected with gear 16 through one-way clutch, rack 15 will mesh with gear 16 in the process of moving upwards.

[0037] As Figures 7-10As shown, the limiting mechanism includes a third electric push rod 17, a first limiting plate 18, a mounting plate 19, a fourth electric push rod 20, a moving plate 21, a second limiting plate 22, and a fifth electric push rod 23. The top left and right sides of the placement plate 132 are symmetrically connected to the third electric push rods 17. The telescopic rods of the two third electric push rods 17 on the left side are connected to the first limiting plate 18, and the telescopic rods of the two third electric push rods 17 on the right side are also connected to the first limiting plate 18. The upper sides of the two first limiting plates 18, which are close to each other, are provided with support parts 181. When the door frame is flipped, the support parts 181 of the first limiting plate 18 can support the door frame and prevent... As the door frame descends, a mounting plate 19 is bolted to the bottom center of the placement plate 132. A fourth electric push rod 20 is connected to the middle of the mounting plate 19. A movable plate 21 is connected to the upper end of the telescopic rod of the fourth electric push rod 20. A second limiting plate 22 is slidably connected to both the front and rear sides of the movable plate 21. The front and rear sides of the middle of the placement plate 132 are provided with receiving grooves for accommodating the second limiting plate 22. A fifth electric push rod 23 is symmetrically connected to the bottom of the movable plate 21 on both the front and rear sides. The telescopic rods of the two fifth electric push rods 23 on the front side are connected to the bottom of the second limiting plate 22 on the front side, and the telescopic rods of the two fifth electric push rods 23 on the rear side are connected to the bottom of the second limiting plate 22 on the rear side.

[0038] like Figure 5 As shown, it also includes a guide sleeve 35. The guide sleeve 35 is connected to the side of the two vertical electric guide rails 4 that are close to each other. The spiral plate 14 is located inside the guide sleeve 35, and the spiral plate 14 and the guide sleeve 35 are slidably connected.

[0039] At the beginning, the telescopic rods of the third electric push rod 17 and the fifth electric push rod 23 are in the elongated state; the workers place four metal plates on the placing plate 132 and place the four metal plates into a door frame shape, control the telescopic rod of the third electric push rod 17 to shorten, drive the two first limiting plates 18 to move in the direction of approaching each other, so that the first limiting plate 18 limits the door frame, at this time, the supporting part 181 of the first limiting plate 18 is in contact with the top of the door frame, then control the telescopic rod of the fourth electric push rod 20 to elongate, drive the moving plate 21 to move upwards, the moving plate 21 drives the second limiting plate 22 to move upwards, lifts the second limiting plate 22, so that the top of the second limiting plate 22 is higher than the top of the placing plate 132, then control the telescopic rod of the fifth electric push rod 23 to shorten, drive the two second limiting plates 22 to move in the direction of approaching each other, so that the second limiting plate 22 limits the door frame, avoids the position of the door frame from being deviated, and automatically limits the door frame, the operation is more convenient, the second limiting plate 22 will enter the containing groove on the placing plate 132, avoids the collision between the second limiting plate 22 and the placing plate 132, control the vertical electric guide rail 4 to drive the lifting plate 5 to move downwards, the lifting plate 5 drives the connecting plate 6 to move downwards, the connecting plate 6 drives the first laser welding head 8 to move downwards, so that the first laser welding head 8 is in contact with the gap at the top of the door frame, control the inclined electric guide rail 7 to drive the first laser welding head 8 to move, so that the first laser welding head 8 welds the gap at the top of the door frame, after the gap at the top of the door frame is welded, control the inclined electric guide rail 7 to drive the second laser welding head 11 to move, so that the second laser welding head 11 is aligned with the gap inside the door frame, control the telescopic rod of the first electric push rod 10 to elongate, drive the second laser welding head 11 to move downwards, so that the second laser welding head 11 welds the gap inside the door frame, after the gap inside the door frame is welded, control the telescopic rod of the first electric push rod 10 to shorten, drive the second laser welding head 11 to move upwards and reset, control the inclined electric guide rail 7 to drive the third laser welding head 13 to move, so that the third laser welding head 13 is aligned with the gap outside the door frame, control the telescopic rod of the second electric push rod 12 to elongate, drive the third laser welding head 13 to move downwards, so that the third laser welding head 13 welds the gap outside the door frame, after the gap outside the door frame is welded, control the telescopic rod of the second electric push rod 12 to shorten, drive the third laser welding head 13 to move upwards and reset, then control the vertical electric guide rail 4 to drive the lifting plate 5 to move upwards, the lifting plate 5 drives the first laser welding head 8, the second laser welding head 11, the third laser welding head 13 and the back plate 14 to move upwards, lifts the first laser welding head 8, the second laser welding head 11 and the third laser welding head 13, provides space for the rotation of the placing plate 132, the upward movement of the back plate 14 will drive the rack 15 to move upwards, the rack 15 will engage with the gear 16 in the process of moving upwards, and drive the gear 16 to rotate, the gear 16 drives the rotating shaft 131 to rotate, the rotating shaft 131 drives the placing plate 132 to rotate,The placement plate 132 drives the door frame to rotate, flipping the door frame so that the gap at the bottom of the door frame faces upwards. This automatic flipping reduces manual intervention, lightens the workload of workers, and improves production efficiency. The supporting part 181 of the first limit plate 18 supports the door frame, preventing it from falling. After the door frame flipping is complete, the vertical electric guide rail 4 is controlled to move the lifting plate 5 downwards. The lifting plate 5 moves the first laser welding head 8, the second laser welding head 11, the third laser welding head 13, and the return plate 14 downwards, lowering the first laser welding head 8, the second laser welding head 11, and the third laser welding head 13 so that the first laser welding head 8 contacts the gap at the bottom of the door frame. The first laser welding head 8 then enters the placement plate 132. Within the gap, to prevent the first laser welding head 8 from colliding with the placement plate 132, the downward movement of the shaped plate 14 will cause the rack 15 to move downward. The rack 15 will drive the gear 16 to rotate in the opposite direction. Under the action of the one-way clutch, the gear 16 will not drive the rotating shaft 131 to rotate. The guide sleeve 35 can guide the shaped plate 14, making the up-and-down movement of the shaped plate 14 more stable. Then, the tilting electric guide rail 7 is controlled to drive the first laser welding head 8 to move, so that the first laser welding head 8 welds the gap at the bottom of the door frame. The lower ends of the second laser welding head 11 and the third laser welding head 13 are both higher than the lower end of the first laser welding head 8, so the second laser welding head 11 and the third laser welding head 13 will not touch the placement plate 132.

[0040] Example 2: Based on Example 1, such as Figures 11-13 As shown, it also includes a support mechanism, which includes a guide frame 24, a insert plate 25, a spring 26, an inclined plate 27, and a pressure rod 28. The guide frames 24 are symmetrically connected to the left and right sides of the mounting box 2, and the insert plates 25 are slidably connected inside the guide frames 24. Two springs 26 are connected between the insert plates 25 and the guide frames 24. The top of the insert plates 25 is connected to the inclined plate 27. The pressure rods 28 are connected to the front and back sides of the middle of the U-shaped plate 14. The pressure rods 28 are in contact with the inclined plates 27. The placement plate 132 has slots 29 symmetrically opened on the left and right sides, and the insert plates 25 are located in the slots 29.

[0041] In the initial state, the pressing rod 28 presses the inclined plate 27, the insertion plate 25 is inserted in the insertion slot 29, the placement plate 132 is supported, the stability of the placement plate 132 is improved, and the spring 26 is in a stretched state; when the hairpin-shaped plate 14 moves upward, the pressing rod 28 moves upward, the pressing rod 28 and the inclined plate 27 are out of contact, under the action of the spring 26, the left and right insertion plates 25 move away from each other, the insertion plate 25 moves out of the insertion slot 29, the placement plate 132 is loosened, and the placement plate 132 can rotate normally; when the hairpin-shaped plate 14 moves downward, the pressing rod 28 moves downward, the pressing rod 28 presses the inclined plate 27, the left and right inclined plates 27 move towards each other, the inclined plate 27 drives the left and right insertion plates 25 to move towards each other, the spring 26 is stretched, the insertion plate 25 is inserted into the insertion slot 29, and the placement plate 132 is supported again.

[0042] As shown in Figure 14 , the jet mechanism further comprises a gas outlet pipe 30, a nozzle 31 and a gas guide pipe 32, two gas outlet pipes 30 are connected to each side of the two connecting plates 6, the two gas outlet pipes 30 on the same connecting plate 6 are symmetrically arranged front and back, the lower end of the gas outlet pipe 30 is connected to the nozzle 31, the nozzle 31 is aligned with the lower end of the first laser welding head 8, so that carbon dioxide can be sprayed to the welding position of the door frame, and the upper ends of the two gas outlet pipes 30 on the same connecting plate 6 are connected to the gas guide pipe 32.

[0043] When the door frame is welded, the gas guide pipe 32 is connected to carbon dioxide, the carbon dioxide is sprayed out of the nozzle 31 through the gas guide pipe 32 and the gas outlet pipe 30, and is sprayed to the welding position of the door frame, so as to promote metal evaporation in the welding process and improve the welding stability.

[0044] As shown in Figure 15 , the unloading mechanism further comprises a gas cylinder 33 and a pushing plate 34, the gas cylinder 33 is connected to the middle of the top rear side of the mounting box 2 through bolts, the pushing plate 34 is connected to the front end of the telescopic rod of the gas cylinder 33, the bottom of the pushing plate 34 is higher than the top of the placement plate 132, and the pushing plate 34 moves forward without colliding with the placement plate 132.

[0045] After the door frame is welded, the extension rod of the third electric push rod 17 is controlled to extend, the two first limiting plates 18 are driven to move away from each other, the welded door frame is loosened, then the extension rod of the fifth electric push rod 23 is controlled to extend, the two second limiting plates 22 are driven to move away from each other, the welded door frame is loosened, then the extension rod of the fourth electric push rod 20 is controlled to shorten, the second limiting plate 22 is driven to move downwards, the second limiting plate 22 is lowered, the top of the second limiting plate 22 is lower than the top of the placing plate 132, so that the welded door frame does not collide with the second limiting plate 22 when the door frame is unloaded, then the extension rod of the air cylinder 33 is controlled to extend, the pushing plate 34 is driven to move forward, the pushing plate 34 pushes the welded door frame out, so that the workers can unload the door frame conveniently.

[0046] The above merely illustrates the embodiments of the present application but should not be used to limit the present application. Any equivalent replacement within the principles of the present application should be included in the protection scope of the present application. The contents not described in detail in the present application belong to the prior art known by the technical personnel in the field.

Claims

1. A metal plate welding device for security door production, comprising a rack (1), a mounting box (2), a mounting frame (3), a vertical electric guide rail (4) and a lifting plate (5), the top of the rack (1) is connected with the mounting box (2), the top of the mounting box (2) is connected with two mounting frames (3), two vertical electric guide rails (4) are installed on the top of the mounting box (2), the vertical electric guide rails (4) are connected with the mounting frames (3), and the sliding blocks of the two vertical electric guide rails (4) are connected with the lifting plate (5), characterized in that, Also include the connecting plate (6), inclined electric guide rail (7), the first laser welding head (8), connecting block (9), the first electric push rod (10), the second laser welding head (11), the second electric push rod (12), the third laser welding head (13), the pivot (131), the placement plate (132), the turnover mechanism and the limiting mechanism, the lifting plate (5) bottom is connected with two connecting plates (6), the connecting plate (6) is connected with two inclined electric guide rails (7), the slider bottom of inclined electric guide rail (7) is installed with first laser welding head (8), first laser welding head (8) is connected with connecting block (9), connecting block (9) is connected with first electric push rod (10) and second electric push rod (12), the telescopic rod of first electric push rod (10) is connected with second laser welding head (11), the telescopic rod of second electric push rod (12) is connected with third laser welding head (13), the installation box (2) is rotatably connected with pivot (131) in left and right sides, and the pivot (131) is connected between two pivot (131), four metal plates are placed on the placement plate (132), and the four metal plates are placed into a door frame shape, the first laser welding head (8), the second laser welding head (11) and the third laser welding head (13) are welded to the gap on the door frame, the lifting plate (5) is equipped with the turnover mechanism for turning over the door frame, and the placement plate (132) is equipped with the limiting mechanism for limiting the door frame.

2. The metal plate welding device for a security door production according to claim 1, characterized in that, The turnover mechanism includes a backplate (14), a rack (15) and a gear (16), the lifting plate (5) bottom is connected with two backplates (14), the backplate (14) is connected with a rack (15), the pivot (131) is connected with a gear (16) through a one-way clutch, and the rack (15) is engaged with the gear (16) in the process of moving upward.

3. The metal plate welding device for a security door production according to claim 2, characterized in that, The limiting mechanism comprises a third electric push rod (17), a first limiting plate (18), a mounting plate (19), a fourth electric push rod (20), a moving plate (21), a second limiting plate (22) and a fifth electric push rod (23), the top of the placing plate (132) is connected with two third electric push rods (17) on the left and right sides, the telescopic rods of the two third electric push rods (17) on the left are jointly connected with the first limiting plate (18), the telescopic rods of the two third electric push rods (17) on the right are also jointly connected with the first limiting plate (18), the first limiting plate (18) is used for limiting the door frame, the upper parts of the two first limiting plates (18) are both provided with a supporting portion (181) used for supporting the door frame, the bottom of the placing plate (132) is connected with the mounting plate (19), the mounting plate (19) is connected with the fourth electric push rod (20), the telescopic rod of the fourth electric push rod (20) is connected with the moving plate (21), the moving plate (21) is slidably connected with the second limiting plate (22) on the front and back sides, the bottom of the moving plate (21) is connected with two fifth electric push rods (23), the telescopic rods of the fifth electric push rods (23) are connected with the second limiting plate (22), and the telescopic rods of the fifth electric push rods (23) can drive the two second limiting plates (22) to move towards each other, so that the second limiting plate (22) limits the door frame.

4. The metal plate welding device for a security door production according to claim 3, characterized in that, The supporting mechanism comprises a guide frame (24), an insertion plate (25), a spring (26), an inclined plate (27) and a pressing rod (28), the guide frames (24) are connected on the left and right sides in the mounting box (2), the insertion plates (25) are slidably connected in the guide frames (24), the springs (26) are connected between the insertion plates (25) and the guide frames (24), the inclined plates (27) are connected on the insertion plates (25), the pressing rods (28) are connected on the meandering plates (14), the left and right sides of the placing plate (132) are both provided with an insertion slot (29), and the pressing rods (28) are used for pressing the inclined plates (27) to insert the insertion plates (25) into the insertion slots (29) and support the placing plate (132).

5. The metal plate welding device for a security door production according to claim 4, characterized in that, The air injection mechanism comprises an air outlet pipe (30), a spray head (31) and an air guide pipe (32), the connecting plates (6) are both connected with two air outlet pipes (30), the air outlet pipes (30) are both connected with the spray heads (31) used for spraying carbon dioxide to the welding position of the door frame, and the air guide pipes (32) are jointly connected with the upper ends of the two air outlet pipes (30) on the same connecting plate (6).

6. The metal plate welding device for a security door production according to claim 5, characterized in that, The unloading mechanism comprises a pneumatic cylinder (33) and a pushing plate (34), the pneumatic cylinder (33) is connected to the top of the mounting box (2), and the pushing plate (34) is connected to the telescopic rod of the pneumatic cylinder (33).

7. The metal plate welding device for a security door production according to claim 6, characterized in that, The mounting box (2) is provided with a guide sleeve (35) used for guiding the meandering plate (14), the meandering plate (14) is located in the guide sleeve (35), and the meandering plate (14) and the guide sleeve (35) are slidably connected.

8. The metal plate welding device for a security door production according to claim 7, characterized in that, The placing plate (132) is provided with a notch at each corner.

9. The metal plate welding device for a security door production according to claim 8, characterized in that, The placing plate (132) is provided with a containing groove for containing the second limiting plate (22) on both front and back sides.

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