A circular pipe fitting inner and outer circumferential weld joint welding mechanism with adjustable multi - degrees of freedom

Abstract

The present invention relates to a circular pipe fitting inner and outer circumferential seam welding mechanism with adjustable multi - degrees of freedom, belonging to the technical field of circular pipe fitting welding. It includes a welding machine platform; on the welding machine platform, a driving mechanism with adjustable height, a clamping mechanism, an adjustable V - shaped support mechanism and a welding manipulator mechanism with multi - degrees of freedom are sequentially installed; the clamping mechanism is connected to the driving mechanism with adjustable height; a groove is provided on the welding machine platform; the adjustable V - shaped support mechanism is installed in the groove. In the present invention application, the circular pipe fitting is placed on the adjustable V - shaped support mechanism, and under the action of the clamping mechanism and the driving mechanism with adjustable height, it moves at a set rotational speed. After the welding manipulator adjusts its position, it remains stationary, and the pipe fitting rotates slowly while the manipulator remains stationary to achieve automatic welding of the inner and outer circumferential seams of the circular pipe fitting. The adjustable V - shaped support mechanism is installed in the groove, which can reduce the height of the support mechanism itself, thereby obtaining a larger adaptation range for the diameter of the circular pipe fitting.

Description

Technical Field

[0001] The present invention relates to the technical field of circular pipe fitting welding, and particularly to a multi-degree-of-freedom adjustable circular pipe fitting inner and outer circumferential seam welding mechanism. Background Art

[0002] For the welding of the inner and outer circumferential seams (flange plates) of existing circular pipe fittings or the splicing of circular pipes, manual welding is mostly used, with low welding efficiency and high labor intensity. For the welding of the inner and outer circumferential seams (flange plates) of existing large circular pipe fittings or the splicing of circular pipes, self-propelled welding manipulators are often used: that is, the circular pipe fitting is fixed first, and an adjustable magnet track is laid beside the inner and outer circumferential seams of the circular pipe fitting to be welded. The welding manipulator runs on the adjustable magnet track to achieve self-propelled automatic welding. In this way, the welding efficiency is greatly improved, and the labor intensity is reduced to a certain extent. However, after a section of welding is completed, the adjustable magnet track and the welding manipulator on it need to be removed first, and then the adjustable magnet track is adjusted and laid again to achieve self-propelled automatic welding. This cycle is repeated. Due to certain errors in each adjustment, the welding accuracy is difficult to accurately guarantee, and the work efficiency is also reduced. In addition, some enterprises also use large numerical control welding machines to achieve one-time clamping and welding forming, with high welding accuracy and high efficiency. However, such large equipment is expensive and requires professional trained technical operators to control, which is difficult for small and medium-sized enterprises to afford.

[0003] In view of the above phenomena, the inventor believes that there is an urgent need for a multi-degree-of-freedom adjustable circular pipe fitting inner and outer circumferential seam welding mechanism to solve the above problems. Summary of the Invention

[0004] The purpose of the present invention is to provide a multi-degree-of-freedom adjustable circular pipe fitting inner and outer circumferential seam welding mechanism to solve the above problems.

[0005] A multi-degree-of-freedom adjustable circular pipe fitting inner and outer circumferential seam welding mechanism provided by the present invention adopts the following technical solutions:

[0006] A multi-degree-of-freedom adjustable circular pipe fitting inner and outer circumferential seam welding mechanism includes a welding machine platform; a height-adjustable driving mechanism, a clamping mechanism, an adjustable V-shaped support mechanism, and a welding manipulator mechanism with multiple degrees of freedom are sequentially installed on the welding machine platform; the clamping mechanism is installed on the height-adjustable driving mechanism; a groove is provided on the welding machine platform; the adjustable V-shaped support mechanism is installed in the groove.

[0007] Further, a second groove is provided on the welding machine platform; the height-adjustable driving mechanism is installed in the second groove.

[0008] Further, the height-adjustable driving mechanism includes:

[0009] Height adjustment mechanism, which includes four electric push rods evenly and symmetrically installed at the bottom of the second groove and a support plate installed at the output end of the electric push rods;

[0010] Power mechanism, which includes a power machine base installed on the support plate. A rotating shaft is rotatably connected in the power machine base through a bearing, and a driving motor is fixedly installed on one side of the power machine base; a pulley one is installed at the output end of the driving motor; a pulley two is installed on the rotating shaft; the pulley one drives the pulley two to rotate through a belt.

[0011] Further, the clamping mechanism is a three-jaw chuck; the three-jaw chuck is fixedly connected to one end of the rotating shaft close to the adjustable V-shaped support mechanism.

[0012] Further, the adjustable V-shaped support mechanism includes:

[0013] Four platform lifting transmission devices, which are evenly and symmetrically installed at the inner bottom of the groove;

[0014] Support plate, which is installed at the top of the platform lifting transmission device; two slide rails are symmetrically installed on the upper part of the support plate;

[0015] Support components, which include a support wheel group A and a support wheel group B symmetrically arranged on the support plate; sliders are symmetrically arranged at the bottoms of the support wheel group A and the support wheel group B; the sliders are slidably connected to the slide rails.

[0016] Further, the number of the adjustable V-shaped support mechanisms can be set as required according to the length of the circular pipe fitting.

[0017] Further, two slide rails two are provided on the welding platform; the welding manipulator mechanism with multiple degrees of freedom includes:

[0018] Machine base, with sliders two symmetrically arranged at the bottom, and the sliders two are slidably connected to the slide rails two;

[0019] Column, which is installed on the upper part of the machine base. Slide rails three are provided on both sides of the column. A lead screw motor is installed at the bottom of the column, and a fixing plate is installed at the top; the output end of the lead screw motor is connected to a lead screw, and the other end of the lead screw is rotatably connected to the fixing plate;

[0020] Welding arm connecting frame, with both sides slidably connected to the slide rails three through chutes and the middle part screwed to the lead screw;

[0021] Receiving frame, which is fixedly installed on the side of the welding arm connecting frame away from the column; a strip hole is provided on the side of the receiving frame away from the column;

[0022] The welding arm is slidably connected inside the accommodating frame; on the side away from the column, the welding arm is provided with a rack, on the side close to the adjustable V-shaped support mechanism, a welding manipulator is installed, and on the side away from the adjustable V-shaped support mechanism, a wire reel is installed.

[0023] The motor is installed on the side of the accommodating frame away from the column, the output end of the motor is connected with a gear matching the rack, and the gear meshes with the rack through a strip-shaped hole.

[0024] Further, symmetrically arranged upper and lower sliding blocks four are provided inside the accommodating frame, sliding rails four matching the sliding blocks four are arranged on the upper and lower sides of the welding arm, and the sliding blocks four and the sliding rails four are slidably connected.

[0025] Further, limiting blocks are arranged on both of the two sliding rails two.

[0026] In summary, the present invention includes the following beneficial technical effects:

[0027] Place the circular pipe fitting on the adjustable V-shaped support mechanism. Under the clamping of the clamping mechanism and the action of the height-adjustable driving mechanism, it moves at a set rotational speed. After the welding manipulator adjusts its position, it remains stationary, and the pipe fitting rotates slowly while the manipulator remains stationary to achieve automatic welding of the inner and outer circumferential seams of the circular pipe fitting. The adjustable V-shaped support mechanism is installed in the groove, which can reduce the height of the support mechanism itself, thereby obtaining a larger adaptation range for the diameter of the circular pipe fitting.

[0028] In the present invention application, a height-adjustable driving mechanism is provided, and the clamping mechanism is installed on the height-adjustable driving mechanism. By the telescopic movement of the electric push rod, the height of the power mechanism and the clamping mechanism is controlled, so as to adapt to clamping circular pipe fittings of different diameters.

[0029] This application is provided with an adjustable V-shaped support mechanism, which mainly functions to support the circular pipe fitting and can limit and reduce welding deformation. Among them, the support tray can be adjusted up and down, and the support wheel group A and the support wheel group B can slide on the sliding rail, so as to realize the support of circular pipe fittings of different sizes; the support wheel group A and the support wheel group B are symmetrically arranged on the support tray to form a V-shaped support, and the support effect is more stable when the circular pipe fitting rotates.

[0030] The present invention application is provided with a welding manipulator mechanism with multiple degrees of freedom, which can slide on the guide rail two. The welding arm connecting frame can move up and down under the action of the lead screw motor rotating the lead screw as required. The welding arm can move left and right on the welding arm connecting frame under the action of the motor driving the gear and the gear rotating the rack, so as to achieve the purpose of automatic welding of circular pipe fittings of different sizes.

[0031] The structure of the present invention is compact. Welding can achieve multi-degree-of-freedom adjustment, has strong practicability, is easy to operate, and can complete all welding of a process with one clamping. The welding accuracy is guaranteed, which effectively improves the production efficiency and reduces the labor intensity of workers. It is a cost-effective circular pipe fitting inner and outer circumferential seam welding mechanism. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 is the structural schematic diagram of the present invention;

[0033] Figure 2 is the structural schematic diagram of the welding machine platform of the present invention;

[0034] Figure 3 is the structural schematic diagram of the height-adjustable driving mechanism and clamping mechanism of the present invention;

[0035] Figure 4 is the structural schematic diagram of the adjustable V-shaped support mechanism of the present invention;

[0036] Figure 5 is the partial structural schematic diagram of the adjustable V-shaped support mechanism of the present invention;

[0037] Figure 6 is the partial structural schematic diagram of the adjustable V-shaped support mechanism of the present invention;

[0038] Figure 7 is the structural schematic diagram of the welding manipulator mechanism with multiple degrees of freedom of the present invention;

[0039] Figure 8 is the structural schematic diagram of the welding arm connecting frame and the welding arm of the present invention;

[0040] Figure 9 is the structural schematic diagram of the welding arm connecting frame and the receiving frame of the present invention;

[0041] Figure 10 is of the present invention Figure 7 Partial enlarged view A.

[0042] Description of the reference numerals: 1. Welding machine platform; 2. Circular pipe fitting; 3. Height-adjustable driving mechanism; 4. Clamping mechanism; 5. Adjustable V-shaped supporting mechanism; 6. Welding manipulator mechanism with multiple degrees of freedom; 7. Groove; 8. Second groove; 9. Electric push rod; 10. Support plate; 11. Power seat; 12. Rotating shaft; 13. Driving motor; 14. First pulley; 15. Second pulley; 16. Belt; 17. Three-jaw chuck; 18. Platform lifting transmission device; 19. Support tray; 20. Slide rail; 21. Support wheel set A; 22. Support wheel set B; 23. Slide block; 24. Second slide rail; 25. Second slide block; 26. Machine base; 27. Column; 28. Second slide rail; 29. Screw motor; 30. Fixed plate; 31. Screw rod; 32. Welding arm connecting frame; 33. Accommodating frame; 34. Strip-shaped hole; 35. Welding arm; 36. Rack; 37. Manipulator; 38. Wire feeding and rewinding wheel; 39. Motor; 40. Gear; 41. Fourth slide block; 42. Fourth slide rail; 43. Limiting block. Detailed implementation manners

[0043] The present invention will be further described in detail below with reference to the accompanying drawings.

[0044] As Figure 1 shown in a specific embodiment of a circular pipe fitting inner and outer circumferential seam welding mechanism with adjustable multiple degrees of freedom, it includes a welding machine platform 1; a height-adjustable driving mechanism 3, a clamping mechanism 4, an adjustable V-shaped supporting mechanism 5 and a welding manipulator mechanism 6 with multiple degrees of freedom are sequentially installed on the welding machine platform 1; the clamping mechanism 4 is installed on the height-adjustable driving mechanism 3; a groove 7 is provided on the welding machine platform 1; the adjustable V-shaped supporting mechanism 5 is installed in the groove 7.

[0045] Specifically, the circular pipe fitting 2 is placed on the adjustable V-shaped supporting mechanism 5, and under the clamping of the clamping mechanism 4 and the action of the height-adjustable driving mechanism 3, it moves at a set rotational speed. After the welding manipulator adjusts its position, it remains stationary, and the circular pipe fitting 2 rotates slowly while the manipulator remains stationary to realize the automatic welding of the inner and outer circumferential seams of the circular pipe fitting 2. The adjustable V-shaped supporting mechanism 5 is installed in the groove 7, which can reduce the height of the supporting mechanism itself, thereby obtaining a larger adaptation range for the diameter of the circular pipe fitting 2.

[0046] In other preferred embodiments, as Figure 2 and Figure 3 shown, a second groove 8 is provided on the welding machine platform 1; the height-adjustable driving mechanism 3 is installed in the second groove 8.

[0047] Specifically, the height-adjustable driving mechanism 3 includes: The height adjustment mechanism includes four electric push rods 9 evenly and symmetrically installed at the bottom of the second groove 8 and a support plate 10 installed at the output end of the electric push rod 9; The power mechanism includes a power machine base 11 installed on the support plate 10. A rotating shaft 12 is rotatably connected to the power machine base 11 through a bearing. A driving motor 13 is fixedly installed on one side of the power machine base 11; A first pulley 14 is installed at the output end of the driving motor 13; A second pulley 15 is installed on the rotating shaft 12; The first pulley 14 drives the second pulley 15 to rotate through a belt 16.

[0048] Specifically, the clamping mechanism 4 is a three-jaw chuck 17; The three-jaw chuck 17 is fixedly connected to one end of the rotating shaft 12 close to the adjustable V-shaped support mechanism 5.

[0049] Specifically, place the circular pipe fitting 2 on the adjustable V-shaped support mechanism 5, fix the adjustable V-shaped support mechanism 5, control the height of the support plate 10 by controlling the telescopic movement of the electric push rod 9, so as to control the height of the three-jaw chuck 17, making the central axis of the three-jaw chuck 17 coincide with the central axis of the circular pipe fitting 2, which is convenient for fixing the circular pipe fitting 2 on the three-jaw chuck 17; Start the driving motor 13, the first pulley 14 drives the second pulley 15 to rotate through the belt 16, thereby driving the rotating shaft 12 to rotate. Since the three-jaw chuck 17 is installed on the rotating shaft 12, the three-jaw chuck 17 clamping the circular pipe fitting 2 rotates at the rotation speed set by the driving motor 13, realizing the automatic welding of the inner and outer circumferential seams of the circular pipe fitting 2.

[0050] In other preferred embodiments, such as Figure 2 and Figures 4 - 6 shown, the adjustable V-shaped support mechanism 5 includes: Four platform lifting transmission devices 18, and the four platform lifting transmission devices 18 are evenly and symmetrically installed at the bottom of the groove 7; The platform lifting transmission device 18 includes a second motor, a worm, a fixed cavity, a turbine and a threaded rod; The worm is connected to the output end of the second motor; The turbine is rotatably connected in the fixed cavity; The worm and the turbine are meshed; The turbine is provided with an internal thread; The turbine is screwed to the threaded rod through the internal thread; The top end of the threaded rod has no thread; A through hole corresponding to the threaded rod is opened at the bottom of the groove 7 to allow the threaded rod to extend to the outside of the bottom of the groove 7; Four fixed seats are installed at the bottom of the support plate 19 corresponding to the threaded rod, and the top end of the threaded rod is rotatably connected in the fixed seat; The second motor drives the worm to rotate. The worm and the turbine are meshed. The turbine is internally provided with an internal thread. The rotation of the turbine drives the threaded rod to move up and down. The upper end of the threaded rod is connected to the support plate, driving the support plate to move up and down; Two slide rails 20 are symmetrically installed on the upper part of the support plate 19; The support assembly includes a support wheel set A 21 and a support wheel set B 22 symmetrically arranged on the support plate 19; Sliders 23 are symmetrically arranged at the bottom of the support wheel set A 21 and the support wheel set B 22; The slider 23 is slidably connected to the slide rail 20.

[0051] Specifically, in this embodiment, in order to ensure a large supporting force, four platform lifting and transmission devices 18 adopt four second motors. In other embodiments, for example, when processing circular pipe fittings with a small pipe diameter, one second motor can be used to control the up and down displacement of four threaded rods through screw drive.

[0052] Specifically, the driving second motor rotates the worm, and the rotation of the turbine drives the up and down displacement of the threaded rod, thereby driving the up and down displacement of the support tray 19, and the height of the support wheel set A21 and the support wheel set B22 themselves can be lowered into the groove 7, so as to obtain a larger adaptation range for the diameter of the circular pipe fitting 2.

[0053] Specifically, the support wheel set A21 and the support wheel set B22 can slide on the slide rail 20. Two groups of rollers are provided on both the support wheel set A21 and the support wheel set B22, forming a V shape, making the rotation of the circular pipe fitting 2 more stable, so as to realize the support of circular pipe fittings 2 of different sizes.

[0054] Specifically, the number of the adjustable V-shaped support mechanisms 5 can be set as required according to the length of the circular pipe fitting.

[0055] In other preferred embodiments, as Figures 7 - 10 shown, two second slide rails 24 are provided on the welding machine platform 1; the welding manipulator mechanism 6 with multiple degrees of freedom includes: sliders two 25 are symmetrically provided at the bottom of the machine base 26, and the sliders two 25 are slidably connected with the second slide rails 24; the column 27 is installed on the upper part of the machine base 26, and third slide rails 28 are provided on both sides of the column 27. A screw motor 29 is installed at the bottom of the column 27, and a fixing plate 30 is installed at the top; the output end of the screw motor 29 is connected with a screw rod 31, and the other end of the screw rod 31 is rotatably connected to the fixing plate 30; both sides of the welding arm connecting frame 32 are slidably connected to the third slide rails 28 through chutes, and a threaded hole is opened in the middle, and is screwed on the screw rod 31 through the threaded hole. Starting the screw motor 29, the screw rod 31 drives the welding arm connecting member 32 to move up and down, so as to drive the welding manipulator 37 to move up and down; the receiving frame 33 is fixedly installed on the side of the welding arm connecting frame 32 away from the column 27; a strip hole 34 is provided on the side of the receiving frame 33 away from the column 27; the welding arm 35 is slidably connected in the receiving frame 33; a rack 36 is provided on the side of the welding arm 35 away from the column 27, a welding manipulator 37 is installed on the side of the welding arm 35 close to the adjustable V-shaped support mechanism 5, and a wire feeding and taking-up wheel 38 is installed on the side away from the adjustable V-shaped support mechanism 5; the motor 39 is installed on the side of the receiving frame 33 away from the column 27, the output end of the motor 39 is connected with a gear 40 matching the rack 36, and the gear 40 is meshed with the rack 36 through the strip hole 34. Starting the motor 39 drives the gear 40 to rotate, and the gear 40 drives the rack 36 to move, so that the welding arm 35 can move left and right.

[0056] Specifically, the welding manipulator mechanism 6 with multiple degrees of freedom can slide on the second slide rail 24. The welding arm connecting frame 32 can move up and down under the action of the lead screw motor 29 rotating the lead screw 31 as required. The welding arm 35 can move left and right on the welding arm connecting frame 32 under the drive of the motor 39 rotating the gear 40 and the gear 40 rotating the rack 36, so that the welding manipulator 37 has multiple degrees of freedom to achieve the purpose of automatically welding circular pipe fittings 2 of different sizes.

[0057] In other preferred embodiments, symmetrically arranged upper and lower sliding blocks four 41 are provided inside the receiving frame 33. Slide rails four 42 matching the sliding blocks four 41 are arranged on the upper and lower sides of the welding arm 35, and the sliding blocks four 41 are slidably connected to the slide rails four 42.

[0058] Specifically, the welding arm 35 is slidably arranged in the receiving frame 33, ensuring the stability of the welding arm 35 when the gear 40 rotates the rack 36 to displace.

[0059] In other preferred embodiments, as Figure 2 shown, limiting blocks 43 are provided on both of the two second slide rails 24.

[0060] Specifically, the limiting block 43 is slidably connected to the second slide rail 24. A bolt is provided on the upper part of the limiting block 43. When manually adjusting the welding manipulator mechanism 6 with multiple degrees of freedom to a specified position, tighten the bolt so that the bottom of the bolt contacts the second slide rail 24 to complete the fixation, ensuring that the second sliding block 25 will not displace during the working process. When the position needs to be adjusted, loosen the bolt, and the limiting block 43 returns to a movable state, and the second sliding block 25 can also displace, ensuring the stability of the machine base 26 during the processing.

[0061] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features. However, such modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A multi-degree-of-freedom adjustable internal and external annular seam welding mechanism for circular pipes, comprising a welding machine platform (1); characterized in that: The welding machine platform (1) is sequentially mounted with a height-adjustable driving mechanism (3), a clamping mechanism (4), an adjustable V-shaped supporting mechanism (5), and a welding manipulator mechanism (6) with multiple degrees of freedom; the clamping mechanism (4) is mounted on the height-adjustable driving mechanism (3); a groove (7) is provided on the welding machine platform (1); and the adjustable V-shaped supporting mechanism (5) is mounted in the groove (7); The adjustable V-shaped support mechanism (5) comprises: Four platform lifting transmission devices (18), the four platform lifting transmission devices (18) being evenly and symmetrically installed at the bottom of the groove (7); A support plate (19), the support plate (19) being mounted on the top of the platform lifting transmission device (18); two slide rails (20) are symmetrically mounted on the upper part of the support plate (19); A support assembly, the support assembly comprising a support wheel group A (21) and a support wheel group B (22) symmetrically arranged on a support plate; a slider (23) is symmetrically arranged at the bottom of each of the support wheel group A (21) and the support wheel group B (22); the slider (23) is slidably connected to the slide rail (20); The welding machine platform (1) is provided with two slide rails (24); the welding manipulator mechanism (6) with multiple degrees of freedom comprises: A machine base (26), wherein a second slide block (25) is symmetrically arranged at the bottom of the machine base (26), and the second slide block (25) is slidably connected to a second slide rail (24); A column (27), the column (27) is installed on the upper part of the machine base (26), two sides of the column (27) are provided with slide rails (28), a screw motor (29) is installed at the bottom of the column (27), and a fixing plate (30) is installed at the top; the output end of the screw motor (29) is connected to a screw (31), and the other end of the screw (31) is rotatably connected to the fixing plate (30); A welding arm connecting frame (32), the two sides of the welding arm connecting frame (32) are slidably connected to the slide rail three (28) through sliding grooves, and the middle part is screwed to the screw rod (31) through a threaded hole; A containing frame (33), the containing frame (33) is fixedly mounted on a side of the welding arm connecting frame (32) away from the column (27); a strip-shaped hole (34) is provided on the side of the containing frame (33) away from the column (27); A welding arm (35), the welding arm (35) is slidably connected in the accommodating frame (33); the welding arm (35) is provided with a rack (36) on a side away from the column (27); a welding manipulator (37) is installed on a side of the welding arm (35) close to the adjustable V-shaped support mechanism (5); and a welding wire retracting wheel (38) is installed on a side away from the adjustable V-shaped support mechanism (5); A motor (39), the motor (39) is mounted on a side of the accommodating frame (33) away from the column (27), the output end of the motor (39) is connected to a gear (40) matching the rack (36), and the gear (40) is meshed with the rack (36) through the bar-shaped hole (34); A slider four (41) symmetrically arranged in the upper and lower parts of the containing frame (33), a slide rail four (42) matching the slider four (41) is arranged on the upper and lower sides of the welding arm (35), and the slider four (41) and the slide rail four (42) are slidably connected; The two slide rails (24) are both provided with limiting blocks (43); The welding machine platform (1) is provided with a second groove (8); the height-adjustable driving mechanism (3) is installed in the second groove (8); The height-adjustable driving mechanism (3) comprises: A height adjustment mechanism, the height adjustment mechanism comprising four electric push rods (9) evenly and symmetrically mounted at the bottom of the second groove (8) and a support plate (10) mounted at the output end of the electric push rods (9); The power mechanism comprises a power machine base (11) mounted on a support plate (10), a rotating shaft (12) is rotatably connected to the power machine base (11) via a bearing, a driving motor (13) is fixedly mounted on one side of the power machine base (11); a pulley 1 (14) is mounted on the output end of the driving motor (13); a pulley 2 (15) is mounted on the rotating shaft (12); the pulley 1 (14) drives the pulley 2 (15) to rotate via a belt (16); The clamping mechanism (4) is a three-jaw chuck (17); the three-jaw chuck (17) is fixedly connected to one end of the rotating shaft (12) close to the adjustable V-shaped support mechanism (5); The number of the adjustable V-shaped supporting mechanisms (5) can be set as required according to the length of the circular pipe (2).

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