A mechanical arm structure for a welding robot

Abstract

The present invention provides a robotic arm structure for a welding robot, comprising: a robotic arm assembly; a mounting frame, the mounting frame being slidably mounted on the final arm of the robotic arm assembly; a swinging device, the swinging device being used to drive the mounting frame to move back and forth horizontally; a rotating device, the rotating device comprising an assembly frame and a second motor, the assembly frame being rotatably mounted in the mounting frame, and the second motor being mounted on the assembly frame; an angle adjustment device, the rotating device being used to drive the assembly frame to rotate; a welding structure, the welding structure comprising a telescopic structure, a welding gun, a rotating shaft, and a fixing frame. The robotic arm structure for a welding robot provided by the present invention can sequentially realize a linear welding trajectory, a zigzag welding trajectory, a crescent-shaped welding trajectory, a circular welding trajectory, etc., and the swing amplitude or rotation diameter of the welding gun can adjust the width of the weld, thereby improving the adaptability of the welding robot.

Description

Technical Field

[0001] The present invention relates to the field of welding robots, and in particular to a mechanical arm structure for welding robots. Background Art

[0002] A welding robot is a highly automated welding equipment that combines robotic arm technology, welding technology and intelligent control systems. It is usually composed of a multi-degree-of-freedom robotic arm, a welding end effector (such as an arc welding gun, a laser welding head), a servo control system and a sensor device. It can replace manual labor to complete various welding tasks.

[0003] During welding, the welding trajectory refers to the path of motion of the welding gun or electrode relative to the workpiece. Different welding methods require a specific welding method, which impacts the quality and efficiency of weld formation. Common welding trajectory types include linear, zigzag, crescent, and circular. The weld width varies for different workpieces, and current welding robots still have room for improvement in adapting to a variety of welding trajectories and adjusting weld width.

[0004] Therefore, it is necessary to provide a mechanical arm structure for a welding robot to solve the above technical problems. Summary of the Invention

[0005] The present invention provides a mechanical arm structure for a welding robot, which solves the problem of how the current welding robot can adapt to a variety of welding trajectories and still have room for improvement in adjusting the width of the weld.

[0006] In order to solve the above technical problems, the present invention provides a mechanical arm structure for a welding robot, comprising: a mechanical arm assembly;

[0007] A mounting frame, the mounting frame being slidably mounted on the final arm of the robotic arm assembly;

[0008] A swing device, the swing device is used to drive the mounting frame to move horizontally back and forth;

[0009] A rotating device, the rotating device comprising an assembly frame and a second motor, the assembly frame being rotatably mounted in the mounting frame, and the second motor being mounted on the assembly frame;

[0010] Angle adjustment device, the rotating device is used to drive the assembly frame to rotate;

[0011] A welding structure comprising a telescopic structure, a welding gun, a rotating shaft and a fixing frame, wherein the top end of the rotating shaft is detachably connected to the output shaft of the second motor, the bottom end of the rotating shaft is mounted on the telescopic structure, the fixing frame is mounted on the telescopic end of the telescopic structure, and the welding gun is mounted on the fixing frame.

[0012] Preferably, the mechanical arm structure for the welding robot also includes a cleaning brush, a connecting frame and a limiting structure. The connecting frame is rotatably installed inside the assembly frame through a support sleeve, the rotating shaft is rotatably connected to the connecting frame, and the cleaning brush is installed on the connecting frame through a connecting rod. The cleaning brush is set at a preset angle to the welding structure, and the limiting structure is used to limit the axial position of the connecting frame.

[0013] Preferably, the mechanical arm structure for the welding robot further includes a spray-sweeping assembly, which includes an air pipe and a nozzle, the air pipe is installed at the bottom of the cleaning brush, and the nozzle is installed on the air pipe.

[0014] Preferably, the angle adjustment device includes a bracket, a first motor and a transmission shaft. The first motor is mounted on the mounting frame through the bracket. The transmission shaft is sleeved on the drive shaft of the first motor and is connected to the drive shaft with a sliding key. A first square hole is opened on the assembly frame, and the transmission shaft is plugged into the first square hole.

[0015] Preferably, the mechanical arm structure for the welding robot also includes a positioning component, which includes a push cylinder, a connecting plate and a limit block. The push cylinder is installed on the bracket, and the connecting plate is installed on the output end of the push cylinder. Two limit blocks are installed on the connecting plate at intervals. Positioning ports are provided at the bottom of the mounting frame and the assembly frame, and the limit blocks are assembled with the two positioning ports.

[0016] Preferably, a second square hole is opened inside the support sleeve, and the second square hole is aligned with the first square hole. A rotating member is installed on the transmission shaft, and the connecting plate is connected to the rotating member through a driving plate.

[0017] Preferably, an assembly tube is provided on the assembly frame, and the assembly tube is sleeved on the support sleeve, and the limiting structure includes a connecting shaft, an elastic member, a pressure ring, a positioning block and a positioning part. The top end of the connecting shaft passes through the assembly frame, the pressure ring is sleeved on the connecting shaft, the elastic member is sleeved on the connecting shaft and is located between the pressure ring and the assembly frame, the positioning block is installed on the bottom end of the connecting shaft, the bottom end of the positioning block passes through the assembly tube and extends to one side of the support sleeve, the positioning part is provided on one side of the positioning block, and the positioning block is set as an inclined surface toward the side of the positioning component, and the end of the support sleeve is provided with two positioning grooves at a preset angle, and the positioning part is inserted into one of the positioning grooves, and the assembly tube is provided with a receiving groove above the positioning part.

[0018] Preferably, the telescopic structure includes a mounting block and a threaded pin, the mounting block is installed at the bottom end of the rotating shaft, one end of the threaded pin is threadedly connected to the mounting block, and the other end of the threaded pin is provided with a square groove, the square groove, the first square hole and the second square hole are aligned in sequence, one end of the fixing frame is rotatably connected to the threaded pin, and the fixing frame is slidably connected to the mounting block.

[0019] Preferably, the telescopic structure further comprises a sliding rod, one end of which is mounted on the fixing frame, and the other end of which is plugged into the mounting block.

[0020] Preferably, the top end of the rotating shaft is configured to be rectangular, and the rotating device further comprises a U-shaped sleeve, which is mounted on the output shaft of the second motor and is sleeved on the top end of the rotating shaft.

[0021] Compared with the related art, the mechanical arm structure for the welding robot provided by the present invention has the following beneficial effects:

[0022] The present invention provides a mechanical arm structure for a welding robot. During welding, after the mechanical arm assembly drives the welding gun in the welding structure to contact the welding position, the mechanical arm assembly drives the welding gun to move along the weld to achieve a linear welding trajectory.

[0023] When the robotic arm assembly drives the welding structure to move linearly, the swing device drives the mounting frame to swing back and forth, and the mounting frame in turn drives the welding structure to swing back and forth through the assembly frame, so that the welding gun can achieve a zigzag welding trajectory;

[0024] While the robotic arm assembly drives the welding structure to move linearly, the second motor drives the fixed frame to rotate back and forth through the rotating shaft, causing the welding gun to rotate back and forth, thereby achieving a crescent-shaped welding trajectory; wherein, the second motor drives the welding gun to make a small circular motion through the rotating shaft and the fixed frame, thereby achieving a circular welding trajectory.

[0025] Among them, the telescopic structure can adjust the distance between the fixed frame and the rotating shaft, so that the swing amplitude or rotation diameter of the welding gun can be adjusted when the rotating shaft rotates, thereby adjusting the width of the weld;

[0026] For a zigzag welding track, the swing amplitude of the swing device can be adjusted to adjust the width of the weld; thereby improving the adaptability of the welding robot. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 A schematic structural diagram of a preferred embodiment of a mechanical arm structure for a welding robot provided by the present invention;

[0028] Figure 2A partial schematic diagram of the mechanical arm structure for a welding robot provided by the present invention;

[0029] Figure 3 A partial cross-sectional view of the mechanical arm structure for a welding robot provided by the present invention;

[0030] Figure 4 for Figure 3 An enlarged schematic diagram of part A is shown;

[0031] Figure 5 for Figure 2 A schematic diagram of another perspective of the mechanical arm structure of the welding robot is shown;

[0032] Figure 6 A schematic diagram of the state of the angle adjustment device provided by the present invention for adjusting the angle of the welding structure;

[0033] Figure 7 This is a schematic diagram of a state in which the angle adjustment device provided by the present invention can drive the connecting frame to rotate;

[0034] Figure 8 A schematic diagram of the state in which the angle adjustment device provided by the present invention is used to drive the threaded pin to rotate;

[0035] Figure 9 This is a schematic diagram of the angle adjustment device provided by the present invention driving the connecting frame to rotate, wherein: Figure 9 (a) is a schematic diagram of a welding structure. Figure 9 (b) is a schematic diagram of using a cleaning brush.

[0036] Numbers in the figure:

[0037] 1. Robotic arm assembly; 101. Final arm;

[0038] 2. Swinging device;

[0039] 3. Mounting frame; 31. Assembly block;

[0040] 4. Angle adjustment device; 41. Bracket; 42. First motor; 43. Transmission shaft; 44. Rotating member;

[0041] 421, drive shaft; 431, square shaft portion;

[0042] 5. Rotating device; 51. Assembly frame; 52. Second motor; 53. U-shaped sleeve;

[0043] 511, first square hole; 512, assembly tube; 513, storage slot;

[0044] 6. Welding structure; 61. Telescopic structure; 62. Welding gun; 63. Rotating shaft; 64. Fixed frame;

[0045] 611, mounting block; 612, threaded pin; 613, slide rod; 614, square groove;

[0046] 7. Positioning assembly; 71. Push cylinder; 72. Connecting plate; 73. Limit block; 74. Driving plate;

[0047] 8. Connecting frame; 81. Support sleeve; 811. Positioning slot;

[0048] 9. Limiting structure; 91. Connecting shaft; 92. Elastic member; 93. Pressing ring; 94. Positioning block; 95. Positioning portion;

[0049] 10. Positioning port;

[0050] 20. Cleaning brush; 201. Connecting rod;

[0051] 30. Spray-sweeping assembly; 301. Air pipe; 302. Spray nozzle. DETAILED DESCRIPTION

[0052] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0053] The invention provides a mechanical arm structure for a welding robot.

[0054] Please refer to Figure 1 and Figure 2 ,In one embodiment of the present invention, the mechanical arm structure for a welding robot comprises: a mechanical arm assembly 1;

[0055] A mounting frame 3, wherein the mounting frame 3 is slidably mounted on the final arm 101 of the robotic arm assembly 1;

[0056] A swing device 2, the swing device 2 is used to drive the mounting frame 3 to move horizontally back and forth;

[0057] A rotating device 5, the rotating device 5 comprising an assembly frame 51 and a second motor 52, the assembly frame 51 being rotatably mounted in the mounting frame 3, and the second motor 52 being mounted on the assembly frame 51;

[0058] Angle adjustment device 4, the rotating device 5 is used to drive the assembly frame 51 to rotate;

[0059] The welding structure 6 includes a telescopic structure 61, a welding gun 62, a rotating shaft 63 and a fixing frame 64. The top end of the rotating shaft 63 is detachably connected to the output shaft of the second motor 52, the bottom end of the rotating shaft 63 is installed on the telescopic structure 61, the fixing frame 64 is installed at the telescopic end of the telescopic structure 61, and the welding gun 62 is installed on the fixing frame 64.

[0060] During welding, the robot arm assembly 1 drives the welding gun 62 in the welding structure 6 to contact the welding position, and then the robot arm assembly 1 drives the welding gun 62 to move along the weld to achieve a linear welding trajectory;

[0061] As the robotic arm assembly 1 drives the welding structure 6 to move linearly, the swing device 2 drives the mounting frame 3 to swing back and forth. The mounting frame 3, in turn, drives the welding structure 6 to swing back and forth through the assembly frame 51, thereby enabling the welding gun 62 to achieve a zigzag welding trajectory (for cap welding of longitudinal seams of pressure vessel cylinders and surface shaping of fillet welds of bridge steel structures).

[0062] When the robotic arm assembly 1 drives the welding structure 6 to move linearly, the second motor 52 drives the fixed frame 64 to rotate back and forth via the rotating shaft 63, causing the welding gun 62 to rotate back and forth, thereby achieving a crescent-shaped welding trajectory (such as the cap welding of pipeline welding (such as the circumferential seam of a natural gas pipeline)). Among them, the second motor 52 drives the welding gun 62 to make a small circular motion via the rotating shaft 63 and the fixed frame 64, thereby achieving a circular welding trajectory (usually used for spot welding or surfacing welding).

[0063] The telescopic structure 61 can adjust the distance between the fixing frame 64 and the rotating shaft 63, thereby adjusting the swing amplitude or rotation diameter of the welding gun 62 when the rotating shaft 63 rotates, thereby adjusting the width of the weld.

[0064] For a zigzag welding trajectory, the swing amplitude of the swing device 2 can be adjusted to adjust the width of the weld; thereby improving the adaptability of the welding robot.

[0065] Among them, an assembly block 31 is provided on one side of the mounting frame 3, and a plurality of support rods are provided inside the final arm 101. In this embodiment, there are four support rods, and the assembly block 31 is sleeved on the support rods to form a sliding assembly.

[0066] As an optional embodiment of the present invention, the swing device 2 includes a drive motor, a cam, and a cam shaft. The drive motor is mounted on the final arm 101. The output shaft of the drive motor passes through the top of the final arm 101 and is connected to the cam. One end of the cam shaft is eccentrically mounted on the cam. A strip-shaped slot is provided on the assembly block 31. The other end of the cam shaft is inserted into the strip-shaped slot. The drive battery drives the cam to rotate back and forth. The cam shaft slides along the strip-shaped slot, thereby driving the assembly block 31 to swing back and forth along the support rod. The assembly block 31 drives the mounting frame 3 to move back and forth, thereby realizing the reciprocating swing function.

[0067] Among them, by adjusting the reciprocating rotation angle of the driving motor, the amplitude of the cam's swing can be adjusted, thereby adjusting the width of the weld during welding.

[0068] As another optional embodiment of this embodiment, the swing device 2 includes a drive device, a screw rod and a nut. The drive device is mounted on the final arm 101. The screw rod is mounted inside the final arm 101 and passes through the assembly block 31. The assembly block 31 is threadedly connected to the screw rod through the nut. The drive device is used to drive the screw rod to rotate back and forth.

[0069] The reciprocating rotation of the screw drives the assembly block 31 to rotate reciprocally through the nut, realizing the reciprocating swing function of the swing device 2. By adjusting the distance that the nut drives the assembly block 31 to move back and forth along the screw, the swing amplitude is increased, thereby adjusting the width of the weld during welding.

[0070] In this embodiment, the robotic arm assembly 1 includes a rotating base, a large arm, a small arm and a final arm 101. The large arm is mounted on the rotating base, and the rotating base can drive the large arm to rotate horizontally. The small arm is mounted on the large arm through a control motor. The small arm is mounted on the large arm through a control motor. The control motor controls the rotation of the large arm and the small arm respectively. The small arm is mounted with a control motor. The final arm 101 is mounted on the output shaft of the control motor for driving the final arm 101 to rotate horizontally.

[0071] The welding robot also includes a control system for controlling the robotic arm to perform welding work.

[0072] See also Figure 5 As a preferred embodiment of this embodiment, the robotic arm structure for the welding robot further includes a cleaning brush 20, a connecting frame 8 and a limiting structure 9. The connecting frame 8 is rotatably mounted inside the assembly frame 51 through a support sleeve 81. The rotating shaft 63 is rotatably connected to the connecting frame 8. The cleaning brush 20 is mounted on the connecting frame 8 through a connecting rod 201. The cleaning brush 20 is set at a preset angle to the welding structure 6. The limiting structure 9 is used to limit the axial position of the connecting frame 8.

[0073] After each welding, the welding slag and the like on the weld need to be cleaned, especially for multi-layer welding, the welding slag and the like need to be cleaned after each welding layer;

[0074] When the welding slag needs to be cleaned, the limiting structure 9 is driven to unlock the axial limit of the connecting frame 8, and then the connecting frame 8 is rotated so that the cleaning brush 20 faces downward, and the welding structure 6 is rotated to one side, such as Figure 9 (a) and Figure 9(b) in the figure; then the robot arm assembly 1 drives the cleaning surface of the cleaning brush 20 to contact the cleaning position, and then the swing device 2 can drive the mounting frame 3 to swing, thereby driving the cleaning brush 20 to swing back and forth to clean the welding surface to be cleaned, thereby eliminating the need to set up additional cleaning equipment for cleaning.

[0075] The cleaning surface of the cleaning brush 20 is a wire brush or sandpaper.

[0076] In this embodiment, the preset angle between the cleaning brush 20 and the welding structure 6 is ninety degrees, that is, the positions of the cleaning brush 20 and the welding structure 6 can be switched by rotating ninety degrees around the center of the support sleeve.

[0077] Connecting sleeves 81 are provided on both sides of the connecting frame 8 to assemble the assembly pipes 512 on both sides of the inner wall of the assembly frame 51 accordingly.

[0078] Please refer again Figure 5 As a preferred embodiment of this embodiment, the robotic arm structure for the welding robot also includes a spray-sweeping assembly 30, which includes an air pipe 301 and a nozzle 302. The air pipe 301 is installed at the bottom of the cleaning brush 20, and the nozzle 302 is installed on the air pipe 301.

[0079] By setting up the spray sweeping assembly 30, after the welding slag and the like on the welding surface are cleaned by the cleaning brush 20, air flow is input to the nozzle 302 through the air supply pipe 301, and the nozzle 302 blows away the cleaned welding slag from the welding surface.

[0080] There are multiple nozzles 302 installed on the gas pipe 301 at intervals.

[0081] The spray sweeping assembly 30 also includes an air pump and a hose. The hose connects the output end of the air pump and the air pipe 301. The air pump can be installed on the robotic arm assembly 1 or installed in other locations through a mounting bracket. The hose has redundant length.

[0082] See also Figure 3 and Figure 4 In this embodiment, the angle adjustment device 4 includes a bracket 41, a first motor 42 and a transmission shaft 43. The first motor 42 is installed on the mounting frame 3 through the bracket 41. The transmission shaft 43 is sleeved on the drive shaft 421 of the first motor 42 and is connected to the drive shaft 421 with a sliding key. A first square hole 511 is opened on the assembly frame 51, and a square shaft portion 431 is provided at one end of the transmission shaft 43, and the square shaft portion 431 is plugged into the first square hole 511.

[0083] When the angle of the welding gun 62 needs to be adjusted to adapt to different welding positions, the first motor 42 drives the transmission shaft 43 to rotate through the drive shaft 421, the transmission shaft 43 drives the assembly frame 51 to rotate, and the assembly frame 51 drives the welding structure 6 to rotate through the connecting frame 8, thereby adjusting the welding angle of the welding gun 62.

[0084] The transmission shaft 43 includes a round shaft portion and a square shaft portion 431. The diameter of the round shaft portion is less than or equal to the side length of the square shaft portion 431. The drive shaft 421 of the first motor 42 is configured as a square shaft, and a corresponding square groove is defined within the transmission shaft 43, so that when the transmission shaft 43 is fitted over the drive shaft 421, a sliding key is formed. Alternatively, a sliding key can be provided on the drive shaft 421, and a corresponding sliding groove is defined within the transmission shaft 43. After the transmission shaft 43 is fitted over the drive shaft 421, the sliding key slides into the sliding groove to form a sliding key assembly.

[0085] See also Figure 3 and Figure 4 As a preferred embodiment of this embodiment, the mechanical arm structure for the welding robot also includes a positioning component 7, which includes a push cylinder 71, a connecting plate 72 and a limit block 73. The push cylinder 71 is installed on the bracket 41, and the connecting plate 72 is installed at the output end of the push cylinder 71. The two limit blocks 73 are installed on the connecting plate 72 at intervals. The bottom of the mounting frame 3 and the assembly frame 51 are both provided with positioning openings 10, and the limit blocks 73 are assembled with the two positioning openings 10.

[0086] By providing the positioning assembly 7, when the angle of the welding structure 6 is not adjusted, the axial position of the mounting frame 3 is limited, thereby preventing the axial force generated by the mounting frame 3 from acting entirely on the drive shaft 421 of the first motor 42, thereby reducing the impact on the drive shaft 421 of the first motor 42;

[0087] When the mounting frame 3 is limited, the limit block 73 is clamped in the positioning hole 10 at the bottom of the mounting frame 3 and the assembly frame 51. When the welding structure 6 is unlocked, the push cylinder 71 pulls the connecting plate 72 to drive the limit block 73 to move. Figure 6 , so that the limiting block 73 moves out of the positioning hole 10 at the bottom of the assembly frame 51 to achieve unlocking.

[0088] Please refer again Figure 3 and Figure 4 As a preferred embodiment of this embodiment, a second square hole is opened inside the support sleeve 81, and the second square hole is aligned with the first square hole 511. A rotating member 44 is installed on the transmission shaft 43, and the connecting plate 72 is connected to the rotating member 44 through a driving plate 74.

[0089] When the angle adjustment device 4 is used to adjust the angle of the welding structure 6, the square shaft portion 431 in the transmission shaft 43 is assembled with the first square hole 511, so that when the first motor 42 is working, the transmission shaft 43 can cooperate with the first square hole 511 to drive the assembly frame 51 to rotate, thereby adjusting the angle of the welding structure 6.

[0090] When the angle adjustment device 4 is used to drive the connecting frame 8 to rotate and adjust the position of the welding structure 6 and the cleaning brush 20, please refer to Figures 6 and 7 , the push cylinder 71 continues to push the connecting plate 72, and the connecting plate 72 drives the transmission shaft 43 to move through the rotating member 44, so that the square shaft portion 431 at the end of the transmission shaft 43 moves out of the first square hole 511 and enters the second square hole in the support sleeve 81. The limiting structure 9 unlocks the axial direction of the connecting frame 8. When the first motor 42 drives the transmission shaft 43 to rotate, the square shaft portion 431 cooperates with the second square hole, driving the connecting frame 8 to rotate ninety degrees, so that the cleaning brush 20 is facing downward, as shown in FIG. Figure 9 As shown, at this time, the round shaft portion of the transmission shaft 43 is located in the first square hole 511 and thus does not drive the assembly frame 51 to rotate;

[0091] At this time, the limiting block 73 is assembled with the positioning opening 10 at the bottom of the assembly frame 51 and the installation frame 3, so as to limit the assembly machine 51 and avoid axial rotation at this time.

[0092] Thus, the angle adjustment device 4 can be used to sequentially adjust the angle of the welding structure 6 and switch the positions of the welding structure 6 and the cleaning brush 20, thereby realizing the switching between the welding function and the cleaning function.

[0093] The rotating member 44 is a bearing or a guide wheel. When it is a guide wheel, the top end of the driving plate 74 is located between the two side walls of the guide wheel.

[0094] Please refer again Figure 3 and Figure 4As an optional method of this embodiment, the assembly frame 51 is provided with an assembly tube 512, and the assembly tube 512 is sleeved on the support sleeve 81. The limiting structure 9 includes a connecting shaft 91, an elastic member 92, a pressure ring 93, a positioning block 94 and a positioning portion 95. The top end of the connecting shaft 91 passes through the assembly frame 51, the pressure ring 93 is sleeved on the connecting shaft 91, the elastic member 92 is sleeved on the connecting shaft 91, and is located between the pressure ring 93 and the assembly frame 51. The positioning block 94 is installed At the bottom end of the connecting shaft 91, the bottom end of the positioning block 94 passes through the assembly tube 512 and extends to one side of the support sleeve 81. The positioning portion 95 is arranged on one side of the positioning block 94. The positioning block 94 is arranged as an inclined surface on the side facing the positioning assembly 7. The end of the support sleeve 81 is provided with two positioning grooves 811 at a preset angle. The positioning portion 95 is inserted into one of the positioning grooves 811. The assembly tube 512 is provided with a receiving groove 513 above the positioning portion 95.

[0095] When adjusting the position of the cleaning brush 20, the square shaft portion 431 of the transmission shaft 43 is inserted into the second square hole inside the support sleeve 81. The square shaft portion 431 squeezes the inclined surface of the positioning block 94, so that the positioning block 94 drives the positioning portion 95 to move out of the positioning groove 811, and the positioning portion 95 enters the receiving groove 513. The positioning block 94 pushes the connecting shaft 91 to drive the pressure ring 93 to compress the elastic member 92, thereby achieving axial unlocking of the connecting frame 8, thereby achieving automatic unlocking.

[0096] When the connecting frame 8 is subsequently rotated 90 degrees, the other positioning groove 811 is aligned with the positioning portion 95. When the transmission shaft 43 moves out of the support sleeve 81, the positioning portion 95 enters the corresponding positioning groove 811 through the action of the elastic member 92.

[0097] Wherein, the elastic member 92 is a spring or a reed elastic member;

[0098] An anti-slip sleeve is provided between the support sleeve 81 and the assembly tube 512 so that the connecting frame 8 will not rotate without the action of external force, thereby improving the stability of the connecting frame 8 .

[0099] As another optional method of this embodiment, the limiting structure 9 includes an electric push rod and a positioning shaft. The electric push rod is installed on the assembly frame 51 and suspended above the assembly tube 512. The positioning shaft is installed at the output end of the electric push rod. The positioning shaft passes through the assembly tube 512 and the support sleeve 81 in sequence.

[0100] See also Figure 4In this embodiment, the telescopic structure 61 includes a mounting block 611 and a threaded pin 612. The mounting block 611 is installed at the bottom end of the rotating shaft 63. One end of the threaded pin 612 is threadedly connected to the mounting block 611. The other end of the threaded pin 612 is provided with a square groove 614. The square groove 614, the first square hole 511 and the second square hole are aligned in sequence. One end of the fixing frame 64 is rotatably connected to the threaded pin 612, and the fixing frame 64 is slidably connected to the mounting block 611.

[0101] When it is necessary to adjust the distance between the welding gun 62 and the rotating shaft 63 to adjust the swing amplitude or rotation radius, the push cylinder 71 drives the square shaft portion 431 of the transmission shaft 43 to be inserted into the square groove 614 through the driving plate 74 and the rotating member 44. At this time, the round shaft portion of the transmission shaft 43 is located in the first square hole 511 and the second square hole, so as not to drive the assembly frame 51 and the connecting frame 8 to rotate. The driving shaft 421 of the first motor 42 rotates clockwise or counterclockwise, and the transmission shaft 43 drives the threaded pin 612 to rotate, thereby driving the fixing frame 64 to separate from or approach the mounting block 611, adjusting the distance between the fixing frame 64 and the rotating shaft 63, thereby adjusting the distance between the welding gun 62 and the rotating shaft 63.

[0102] The angle adjustment device 4 can thus be used to adjust the angle of the welding structure 6 and switch the positions of the welding structure 6 and the cleaning brush 20 in turn, realize the switching between the welding function and the cleaning function, and adjust the swing amplitude or rotation radius of the welding gun 62 during welding.

[0103] When the square shaft portion 431 is inserted into the square groove 614 , it is not completely inserted into the square groove 614 , so that the threaded pin 612 can move left and right relative to the square shaft portion 431 to achieve adjustment.

[0104] Among them, preferably, a positioning hole 10 is also opened at the bottom of the connecting frame 8. When the square shaft portion 431 is inserted into the square groove 614, the limit block 73 can be inserted into the positioning hole 10 at the bottom of the connecting frame 8 to assist in limiting the axial direction of the connecting frame 8.

[0105] In other embodiments, the telescopic structure 61 includes a mounting block 611 and an electric push rod, the mounting block 611 is mounted at the bottom end of the rotating shaft 63, the electric push rod is horizontally mounted on the mounting block 611, and the fixing frame 64 is mounted at the output end of the electric push rod.

[0106] As a preferred embodiment of this embodiment, the telescopic structure 61 further includes a sliding rod 613 , one end of which is mounted on the fixing frame 64 , and the other end of which is plugged into the mounting block 611 .

[0107] By providing the sliding rod 613 , the axial position of the fixing frame 64 is limited to prevent the fixing frame 64 from rotating and deviating.

[0108] There are multiple sliding rods 613 , two in this embodiment, which are mounted on the fixing frame 64 and located on both sides of the threaded pin 612 .

[0109] See also Figure 2 As an optional method of this embodiment, the top end of the rotating shaft 63 is set to be rectangular, and the rotating device 5 also includes a U-shaped sleeve 53, which is installed on the output shaft of the second motor 52, and the U-shaped sleeve 53 is sleeved on the top end of the rotating shaft 63.

[0110] When the welding structure 6 needs to be driven to rotate, the second motor 52 drives the rotating shaft 63 to rotate through the U-shaped sleeve 53 and the rectangular portion at the top of the rotating shaft 63, thereby driving the welding structure 6 to rotate;

[0111] Furthermore, when the welding mechanism 6 and the cleaning brush 20 are switched, the rotating shaft 63 can be separated from the U-shaped sleeve 53 , making disassembly simple.

[0112] As another optional method of this embodiment, a U-shaped sleeve 53 can also be provided at the top end of the rotating shaft 63, and a rectangular portion can be provided at the output end of the second motor 52, and the rectangular portion can be inserted into the U-shaped sleeve 53 to achieve a detachable connection.

[0113] In this embodiment, the push cylinder 71 can be a pneumatic cylinder, a hydraulic cylinder, or an electric push rod.

[0114] The working principle of the mechanical arm structure for the welding robot provided by the present invention is as follows:

[0115] During welding, the robot arm assembly 1 drives the welding gun 62 in the welding structure 6 to contact the welding position, and then the robot arm assembly 1 drives the welding gun 62 to move along the weld to achieve a linear welding trajectory;

[0116] As the robotic arm assembly 1 drives the welding structure 6 to move linearly, the swing device 2 drives the mounting frame 3 to swing back and forth. The mounting frame 3, in turn, drives the welding structure 6 to swing back and forth through the assembly frame 51, thereby enabling the welding gun 62 to achieve a zigzag welding trajectory (for cap welding of longitudinal seams of pressure vessel cylinders and surface shaping of fillet welds of bridge steel structures).

[0117] When the robotic arm assembly 1 drives the welding structure 6 to move linearly, the second motor 52 drives the fixed frame 64 to rotate back and forth via the rotating shaft 63, causing the welding gun 62 to rotate back and forth, thereby achieving a crescent-shaped welding trajectory (such as the cap welding of pipeline welding (such as the circumferential seam of a natural gas pipeline)). Among them, the second motor 52 drives the welding gun 62 to make a small circular motion via the rotating shaft 63 and the fixed frame 64, thereby achieving a circular welding trajectory (usually used for spot welding or surfacing welding).

[0118] The telescopic structure 61 can adjust the distance between the fixing frame 64 and the rotating shaft 63, thereby adjusting the swing amplitude or rotation diameter of the welding gun 62 when the rotating shaft 63 rotates, thereby adjusting the width of the weld.

[0119] For a zigzag welding trajectory, the swing amplitude of the swing device 2 can be adjusted to adjust the width of the weld; thereby improving the adaptability of the welding robot.

[0120] After each welding, the welding slag and the like on the weld need to be cleaned, especially for multi-layer welding, the welding slag and the like need to be cleaned after each welding layer;

[0121] When the welding slag needs to be cleaned, the limiting structure 9 is driven to unlock the axial limit of the connecting frame 8, and then the connecting frame 8 is rotated so that the cleaning brush 20 faces downward, and the welding structure 6 is rotated to one side, such as Figure 9 (a) and Figure 9 (b) in the figure; then the robot arm assembly 1 drives the cleaning surface of the cleaning brush 20 to contact the cleaning position, and then the swing device 2 can drive the mounting frame 3 to swing, thereby driving the cleaning brush 20 to swing back and forth to clean the welding surface to be cleaned, thereby eliminating the need to set up additional cleaning equipment for cleaning.

[0122] When the angle adjustment device 4 is used to adjust the angle of the welding structure 6, the square shaft portion 431 in the transmission shaft 43 is assembled with the first square hole 511, so that when the first motor 42 is working, the transmission shaft 43 can cooperate with the first square hole 511 to drive the assembly frame 51 to rotate, thereby adjusting the angle of the welding structure 6.

[0123] When the angle adjustment device 4 is used to drive the connecting frame 8 to rotate and adjust the position of the welding structure 6 and the cleaning brush 20, please refer to Figures 6 and 7 , the push cylinder 71 continues to push the connecting plate 72, and the connecting plate 72 drives the transmission shaft 43 to move through the rotating member 44, so that the square shaft portion 431 at the end of the transmission shaft 43 moves out of the first square hole 511 and enters the second square hole in the support sleeve 81. The limiting structure 9 unlocks the axial direction of the connecting frame 8. When the first motor 42 drives the transmission shaft 43 to rotate, the square shaft portion 431 cooperates with the second square hole, driving the connecting frame 8 to rotate ninety degrees, so that the cleaning brush 20 is facing downward, as shown in FIG. Figure 9 As shown, at this time, the round shaft portion of the transmission shaft 43 is located in the first square hole 511 and thus does not drive the assembly frame 51 to rotate;

[0124] At this time, the limit block 73 is assembled with the assembly frame 51 and the positioning opening 10 at the bottom of the mounting frame 3, so as to limit the assembly machine 51 and prevent axial rotation at this time;

[0125] When it is necessary to adjust the distance between the welding gun 62 and the rotating shaft 63 to adjust the swing amplitude or rotation radius, the push cylinder 71 drives the square shaft portion 431 of the transmission shaft 43 to be inserted into the square groove 614 through the driving plate 74 and the rotating member 44. At this time, the round shaft portion of the transmission shaft 43 is located in the first square hole 511 and the second square hole, so as not to drive the assembly frame 51 and the connecting frame 8 to rotate. The driving shaft 421 of the first motor 42 rotates clockwise or counterclockwise, and the transmission shaft 43 drives the threaded pin 612 to rotate, thereby driving the fixing frame 64 to separate from or approach the mounting block 611, adjusting the distance between the fixing frame 64 and the rotating shaft 63, thereby adjusting the distance between the welding gun 62 and the rotating shaft 63.

[0126] The angle adjustment device 4 can thus be used to adjust the angle of the welding structure 6 and switch the positions of the welding structure 6 and the cleaning brush 20 in turn, realize the switching between the welding function and the cleaning function, and adjust the swing amplitude or rotation radius of the welding gun 62 during welding.

[0127] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention description and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A mechanical arm structure for a welding robot, characterized in that: include: Robotic arm assembly; A mounting frame, the mounting frame being slidably mounted on the final arm of the robotic arm assembly; A swing device, the swing device is used to drive the mounting frame to move horizontally back and forth; A rotating device, the rotating device comprising an assembly frame and a second motor, the assembly frame being rotatably mounted in the mounting frame, and the second motor being mounted on the assembly frame; Angle adjustment device, the rotating device is used to drive the assembly frame to rotate; The welding structure includes a telescopic structure, a welding gun, a rotating shaft and a fixed frame. The top end of the rotating shaft is detachably connected to the output shaft of the second motor, the bottom end of the rotating shaft is installed on the telescopic structure, the fixed frame is installed on the telescopic end of the telescopic structure, and the welding gun is installed on the fixed frame. The mechanical arm structure for the welding robot also includes a cleaning brush, a connecting frame and a limiting structure. The connecting frame is rotatably installed inside the assembly frame through a support sleeve, the rotating shaft is rotatably connected to the connecting frame, the cleaning brush is installed on the connecting frame through a connecting rod, the cleaning brush is set at a preset angle to the welding structure, and the limiting structure is used to limit the axial position of the connecting frame The angle adjustment device includes a bracket, a first motor and a transmission shaft. The first motor is installed on the mounting bracket through the bracket. The transmission shaft is sleeved on the drive shaft of the first motor and is connected to the drive shaft sliding key. A first square hole is opened on the assembly frame, and the transmission shaft is plugged into the first square hole. The mechanical arm structure for the welding robot also includes a positioning component, and the positioning component includes a push cylinder, a connecting plate and a limit block. The push cylinder is installed on the bracket, and the connecting plate is installed at the output end of the push cylinder. The two limit blocks are installed on the connecting plate at intervals. Positioning holes are opened at the bottom of the mounting frame and the assembly frame, and the limit block is assembled with the two positioning holes.

2. The mechanical arm structure for a welding robot according to claim 1, characterized in that: The mechanical arm structure for the welding robot also includes a spray-sweeping assembly, which includes an air pipe and a nozzle. The air pipe is installed at the bottom of the cleaning brush, and the nozzle is installed on the air pipe.

3. The mechanical arm structure for a welding robot according to claim 1, characterized in that: A second square hole is formed inside the support sleeve, and the second square hole is aligned with the first square hole. A rotating member is installed on the transmission shaft, and the connecting plate is connected to the rotating member through a driving plate.

4. The mechanical arm structure for a welding robot according to claim 1, characterized in that: The assembly frame is provided with an assembly tube, and the assembly tube is sleeved on the support sleeve. The limiting structure includes a connecting shaft, an elastic member, a pressure ring, a positioning block and a positioning portion. The top end of the connecting shaft passes through the assembly frame, the pressure ring is sleeved on the connecting shaft, the elastic member is sleeved on the connecting shaft and is located between the pressure ring and the assembly frame, the positioning block is installed on the bottom end of the connecting shaft, the bottom end of the positioning block passes through the assembly tube and extends to one side of the support sleeve, the positioning portion is provided on one side of the positioning block, and the positioning block is set as an inclined surface toward the side of the positioning component. The end of the support sleeve is provided with two positioning grooves at a preset angle, and the positioning portion is inserted into one of the positioning grooves. The assembly tube is provided with a receiving groove above the positioning portion.

5. The mechanical arm structure for a welding robot according to claim 3, characterized in that: The telescopic structure includes a mounting block and a threaded pin. The mounting block is mounted on the bottom end of the rotating shaft. One end of the threaded pin is threadedly connected to the mounting block. The other end of the threaded pin is provided with a square groove. The square groove, the first square hole and the second square hole are aligned in sequence. One end of the fixing frame is rotatably connected to the threaded pin, and the fixing frame is slidably connected to the mounting block.

6. The mechanical arm structure for a welding robot according to claim 5, characterized in that: The telescopic structure further comprises a sliding rod, one end of which is mounted on the fixing frame, and the other end of which is plugged into the mounting block.

7. The mechanical arm structure for a welding robot according to claim 1, characterized in that: The top end of the rotating shaft is configured as a rectangle. The rotating device further comprises a U-shaped sleeve, which is mounted on the output shaft of the second motor. The U-shaped sleeve is sleeved on the top end of the rotating shaft.

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