An industrial welding robot with gas protection

Abstract

This invention discloses an industrial welding robot with gas protection, comprising: a fixed base on which a robotic arm is rotatably mounted via a waist joint turntable; a wrist actuator mounted at the end of the robotic arm, with a mounting shaft on the wrist actuator; a coupling frame fixed to the mounting shaft, with a welding torch assembly mounted below the coupling frame; a wire feed tube fixed to one side of the welding torch assembly via a clamp; and a shielding gas unit inclinedly disposed on one side of the nozzle of the welding torch assembly, wherein an airflow sleeve is coaxially fixed inside the nozzle, and an airflow hole is provided on its side wall at the airflow sleeve. In this invention, a shielding gas delivery channel is provided inside the nozzle, and a shielding gas unit is also assembled around the nozzle. The shielding gas can be sprayed out along the nozzle axis to directly cover the arc and the core area of ​​the molten pool, and can also be supplemented by being sprayed out laterally through the shielding gas unit, which can counteract the disturbance of external airflow to the main airflow and significantly improve wind resistance.

Description

Technical Field

[0001] This invention belongs to the field of welding robot technology, specifically an industrial welding robot with gas protection. Background Technology

[0002] Industrial welding robots are automated devices that combine robotics, welding processes, and sensor technology to complete welding tasks efficiently and accurately. However, in traditional technology, the welding robot nozzle only sprays shielding gas along the welding torch axis, forming a conical gas shield. This results in insufficient gas concentration at the edge of the molten pool and in the heat-affected zone (especially in deep bevels and fillet weld sidewalls), which easily leads to oxidation. Furthermore, traditional systems cannot dynamically adjust the airflow distribution according to the welding position (flat / vertical / overhead) or joint type. In particular, during overhead welding, gravity causes the molten pool to sag, but the airflow is still supplied according to the flat welding parameters, resulting in a very high probability of shielding failure. Summary of the Invention

[0003] To achieve the above objectives, the present invention provides the following technical solution: an industrial welding robot with gas protection, comprising:

[0004] A fixed base, on the upper surface of which a robotic arm is mounted via a waist joint turntable;

[0005] A wrist actuator is installed at the end of a robotic arm, and a mounting shaft is provided on the wrist actuator;

[0006] A coupling frame is fixed on a mounting shaft, and a welding gun device is mounted below the coupling frame. A nozzle is provided at the lower end of the welding gun device.

[0007] The wire feed tube is fixed to one side of the welding torch assembly by a clamp.

[0008] The protective gas unit is inclinedly installed on one side of the nozzle of the welding torch device. A gas flow sleeve is coaxially fixed inside the nozzle, and a gas flow hole is opened on the side wall of the nozzle at the gas flow sleeve. The gas flow hole is connected to the protective gas unit.

[0009] Furthermore, as a preferred embodiment, the coupling frame is constructed in an L-shape, a rotating shaft seat is rotatably connected to the coupling frame, a coupling tube is vertically fixed below the rotating shaft seat, and a rotating shaft is rotatably connected inside the coupling tube;

[0010] The other end of the coupling tube is provided with a suspension plate fixed to the rotating shaft, and the welding gun device is fixed on the suspension plate.

[0011] Furthermore, as a preferred embodiment, the wire feeding tube is rotatably connected to a wire guide wheel, and a fixed paste tube is provided inside the wire feeding tube below the wire guide wheel. A bypass channel is radially opened on the side wall of the fixed paste tube, and a paste feeding tube is sealed and connected to the side wall of the wire feeding tube. The paste feeding tube is connected to the bypass channel.

[0012] The wire feeding tube is equipped with flow-stopping sleeves at the upper and lower ends of the fixed paste tube.

[0013] Furthermore, as a preferred embodiment, the paste delivery tube is externally connected to a flexible tube, and the flexible tube contains alloy paste.

[0014] Furthermore, preferably, the protective gas unit includes:

[0015] An air jet pipe has an extension plate fixed to its outer wall. An air passage communicating with an airflow hole is opened in the extension plate. An air hole is opened on the air jet pipe, and the air hole is sealed and connected to the air passage.

[0016] An inner ring sleeve is coaxially disposed inside the jet pipe, and an inner branch pipe is fixed at the center inside the jet pipe;

[0017] A sealing ring sleeve is slidably sleeved outside the inner branch pipe. The inner wall of the inner ring sleeve is provided with an annular guide cavity, and the sealing ring sleeve is provided with a fixed ring cavity. Multiple ribs are fixed circumferentially between the annular guide cavity and the fixed ring cavity.

[0018] The duct is formed in each of the aforementioned stiffeners, and the two ends of the duct are respectively connected to the annular guide cavity and the fixed annular cavity;

[0019] The upper and lower rows of holes are distributed vertically and are opened on the side wall of the inner branch pipe. The inner wall of the sealing ring is provided with a diversion port.

[0020] The diffuser is fixed to the lower end of the jet pipe.

[0021] Furthermore, as a preferred embodiment, the inner ring sleeve is slidably connected to the jet pipe, and a straight groove is formed on the outer wall of the inner ring sleeve, which is connected to the air hole;

[0022] The inner branch pipe is provided with a partition plate between the upper and lower rows of holes. The partition plate divides the interior of the inner branch pipe into two independent channels. An air hood is fixed to the upper end of the inner branch pipe.

[0023] A diffuser is fixed above the inside of the jet pipe.

[0024] Furthermore, preferably, one end of the extension plate is connected and fixed to the nozzle, and the air hole is connected to the airflow hole through the air passage, and the jet pipe is inclined downward toward the nozzle.

[0025] Furthermore, as a preferred embodiment, the diffuser has an arc-shaped cross-section, with its center located above the diffuser.

[0026] Furthermore, as a preferred embodiment, during the synchronous up-and-down sliding of the sealing ring sleeve with the inner ring sleeve, the diversion port is simultaneously connected to the upper row of holes and the lower row of holes, or connected to one of them individually.

[0027] Furthermore, as a preferred embodiment, an adjusting ring is rotatably connected to the upper part of the jet pipe. The adjusting ring is sleeved outside the inner ring sleeve, and a guide pin is vertically fixed on the side wall of the inner ring sleeve. An inclined guide groove is formed on the inner wall of the adjusting ring, and the guide pin is slidably connected to the inclined guide groove.

[0028] A bidirectional motor is provided at the upper end of the jet pipe, and the output end of the bidirectional motor is fixed to the adjusting ring.

[0029] Compared with the prior art, the beneficial effects of the present invention are:

[0030] In this invention, the welding gun of the industrial welding robot is equipped with a wire feed tube. The wire feed tube can transmit welding wire during welding operations and coat the surface of the welding wire with a layer of low-temperature eutectic alloy paste through a fixed paste tube inside. This allows the paste to quickly dissolve and cover the weld during welding, isolating air and completely evaporating at the high welding temperature without leaving any residue. At the same time, a protective gas delivery channel is provided inside the nozzle, and a protective gas unit is also equipped around the nozzle. The protective gas can be sprayed out along the nozzle axis to directly cover the core area of ​​the electric arc pool, or it can be supplemented by being sprayed out laterally through the protective gas unit to form a lateral gas barrier. This avoids the protective blind zone caused by a single axial airflow and can also counteract the disturbance of the external airflow to the main airflow, significantly improving wind resistance.

[0031] Within this protective gas unit, the protective gas can be divided into two separate paths: one is a concentrated jet path guided and delivered by the inner branch pipe, and the other is a wide-range spray path blocked in the opposite direction by the diffuser plate and diffused by the diffuser cover. This allows for the formation of a fractal protective gas curtain with "center anchoring and edge buffering" through the coupling of high-energy jet and low-speed diffusion field, which is suitable for various welding scenarios. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0033] Figure 2 This is a schematic diagram of the connection structure between the welding torch device and the wire feeding tube in this invention;

[0034] Figure 3 This is a schematic diagram of the nozzle structure in this invention;

[0035] Figure 4 This is a schematic diagram of the coupling frame in this invention;

[0036] Figure 5 This is a schematic diagram of the wire feeding tube in this invention;

[0037] Figure 6 This is a schematic diagram of the protective gas unit in this invention;

[0038] Figure 7 for Figure 6 Enlarged structural diagram at point A;

[0039] In the diagram: 1. Robotic arm; 11. Fixed base; 12. Mounting shaft; 2. Coupling bracket; 21. Rotary shaft seat; 22. Coupling tube; 23. Suspension plate; 3. Welding torch assembly; 31. Nozzle; 32. Airflow sleeve; 33. Airflow hole; 34. Jacket; 4. Wire feed tube; 41. Wire guide wheel; 42. Fixed paste tube; 43. Bypass channel; 44. Paste feed tube; 45. Cut-off sleeve; 5. Shielding gas unit; 51. 511. Jet pipe; 52. Air hole; 53. Extension plate; 54. Air passage; 55. Rib; 56. Channel; 57. Diffuser; 58. Adjusting ring; 69. Bidirectional motor; 60. Inner ring sleeve; 61. Inner branch pipe; 62. Sealing ring sleeve; 62. Fixed ring cavity; 63. Annular guide cavity; 64. Upper row of holes; 65. Lower row of holes; 66. Diverter port; 67. Straight groove port; 68. Air hood; 69. Diffuser plate. Detailed Implementation

[0040] Please see Figures 1-7 In this embodiment of the invention, an industrial welding robot with gas protection includes:

[0041] The fixed base 11 has a robotic arm 1 mounted on its upper surface via a waist joint turntable. The waist joint turntable adopts a dual feedback structure of harmonic reducer and absolute encoder to ensure that the positioning accuracy of the turntable is ≤±0.05° during 360° rotation, avoiding misalignment of protective gas coverage due to welding path deviation. The arm body of the robotic arm 1 adopts a hollow structure of carbon fiber composite material, which reduces weight (40% weight reduction compared to traditional steel arms) while the surface can be embedded with protective gas delivery branch pipe (pressure resistant 1MPa) to reduce external pipeline drag interference.

[0042] A wrist actuator is installed at the end of the robotic arm 1, and a mounting shaft 12 is provided on the wrist actuator;

[0043] A coupling frame 2 is fixed on the mounting shaft 12. A welding gun device 3 is mounted below the coupling frame 2. A nozzle 31 is provided at the lower end of the welding gun device 3.

[0044] The wire feeding tube 4 is fixed to one side of the welding gun device 3 by the sleeve 34, and is used to stably feed the welding wire during the welding process;

[0045] The shielding gas unit 5 is inclinedly disposed on one side of the nozzle 31 of the welding torch device 3. An airflow sleeve 32 is coaxially fixed inside the nozzle 31, and an airflow hole 33 is provided on the side wall of the nozzle 31 at the airflow sleeve. The airflow hole 33 is connected to the shielding gas unit 5. The nozzle 31 is provided with a shielding gas delivery channel. Part of the shielding gas can be sprayed out in a straight line along the nozzle 31, while the other part enters the gap between the airflow sleeve 32 and the nozzle 31, and then flows through the airflow hole 33 into the shielding gas unit 5. The shielding gas unit 5 and the axis of the nozzle 31 form an angle of 45° to 60°. The lateral airflow delivered by the shielding gas unit 5 and the axial airflow in the nozzle can converge and form a spiral converging air curtain above the molten pool, expanding the protection range by more than 20%.

[0046] In this embodiment, the coupling frame 2 is constructed in an L-shape, and a rotating shaft seat 21 is rotatably connected to the coupling frame 2. A coupling tube 22 is vertically fixed below the rotating shaft seat 21, and a rotating shaft is rotatably connected inside the coupling tube 22.

[0047] The other end of the coupling tube 22 is provided with a suspension plate 23 fixed to the rotating shaft. The welding gun device 3 is fixed on the suspension plate 23 and can be fixed by quick-release clamps. It supports changing the welding gun type (such as MIG / TIG switching) within 10 seconds.

[0048] In a preferred embodiment, a wire guide wheel 41 is rotatably connected inside the wire feeding tube 4, and the welding wire inside the wire feeding tube 4 can be smoothly fed by the wire guide wheel 41. A fixed paste tube 42 is provided inside the wire feeding tube 4 below the wire guide wheel 41. A bypass channel 43 is radially opened on the side wall of the fixed paste tube 42. A paste feeding tube 44 is sealed and connected to the side wall of the wire feeding tube 4, and the paste feeding tube 44 is connected to the bypass channel 43.

[0049] Inside the wire feeding tube 4, at the upper and lower ends of the fixed paste tube 42, respectively, there are flow-stopping sleeves 45.

[0050] In this embodiment, the paste delivery tube 44 is externally connected to a flexible tube, which delivers alloy paste. The alloy paste can be a low-temperature eutectic alloy paste (or a decomposable polymer gel, etc.), with a melting point much lower than the welding temperature (such as bismuth-based alloys, melting point <200°C). During welding, it melts rapidly, covering the weld and isolating air. Specifically, the alloy paste can enter the bypass channel 43 through the paste delivery tube 44 and continuously flow into the fixed paste tube 42, thereby filling the interior of the fixed paste tube 42. At this time, when the welding wire is continuously delivered, the alloy paste can coat its surface to form a coating layer, thereby completely evaporating at the high welding temperature without leaving any residue.

[0051] In this embodiment, the protective gas unit 5 includes:

[0052] The jet pipe 51 has an extension plate 52 fixed to its outer wall. The extension plate 52 has an air passage 53 that communicates with the airflow hole 33. The jet pipe 51 has an air hole 511. The air hole 511 can be sealed and connected to the air passage 53 so that the protective gas entering the gap between the airflow sleeve 32 and the nozzle 31 can flow into the air hole 511 through the air passage 53.

[0053] The inner ring sleeve 6 is coaxially arranged inside the jet pipe 51, and the inner branch pipe 61 is fixed at the center inside the jet pipe 51;

[0054] A sealing ring sleeve 62 is slidably sleeved outside the inner branch pipe 61. The inner wall of the inner ring sleeve 6 is provided with an annular guide cavity 63, and the sealing ring sleeve 62 is provided with a fixed annular cavity 621. Multiple reinforcing bars 54 are circumferentially fixed between the annular guide cavity 63 and the fixed annular cavity 621.

[0055] The channel 55 is formed in each of the ribs 54, and the two ends of the channel 55 are respectively connected to the annular guide cavity 63 and the fixed annular cavity 621; wherein, the protective gas delivered in the air hole 511 can preferentially enter the annular guide cavity 63 of the inner ring sleeve 6, and then flow into the fixed annular cavity 621 of the sealing ring sleeve 62 through the channel 55 in each rib 54.

[0056] The upper row of holes 64 and the lower row of holes 65 are distributed vertically and are opened on the side wall of the inner branch pipe 61. The inner wall of the sealing ring sleeve 62 is provided with a diversion port 66. The protective gas entering the fixed ring cavity 621 can enter the upper row of holes 64 and the lower row of holes 65 through the diversion port 66, and then the protective gas is sprayed out by the inner branch pipe 61.

[0057] The diffuser 56 is fixed to the lower end of the jet pipe 51.

[0058] In this embodiment, the inner ring sleeve 6 is slidably connected to the jet pipe 51, and a straight groove 67 is provided on the outer wall of the inner ring sleeve 6. The straight groove 67 is always connected to the air hole 511 to ensure the gas delivery sealing.

[0059] The inner branch pipe 61 is provided with an isolation rib between the upper row of holes 64 and the lower row of holes 65. The isolation rib divides the interior of the inner branch pipe 61 into two independent channels. An air cover 68 is fixed to the upper end of the inner branch pipe 61.

[0060] A diffuser plate 69 is fixed above the interior of the jet pipe 51. This means that the protective gas entering the sealing ring 62 can be transported upward along the inner branch pipe 61 through the upper row hole 64 and discharged from the gas cover 68 at the upper end of the inner branch pipe 61. On the other hand, it can be transported downward along the inner branch pipe 61 through the lower row hole 65 and discharged through the concentrated jet at the lower end of the inner branch pipe 61, thus forming two flow paths.

[0061] In a preferred embodiment, one end of the extension plate 52 is connected and fixed to the nozzle 31, and the air hole 511 is connected to the air flow hole 33 through 53. The air jet pipe 51 is inclined downward toward the nozzle 31 so that the protective gas unit 5 can efficiently supply gas to the weld pool.

[0062] In this embodiment, the diffuser plate 69 has an arc-shaped cross-section, and its center is located above the diffuser plate 69.

[0063] In this embodiment, during the synchronous up-and-down sliding of the sealing ring 62 with the inner ring 6, the diversion port 66 is simultaneously connected to the upper row of holes 64 and the lower row of holes 65, or connected to one of them individually. Specifically, when the diversion port 66 is connected to the upper row of holes 64, the protective gas is transported upward along the inner branch pipe 61. At this time, it can flow and impact the surface of the diffuser plate 69 through the gas cover 68, thereby fully diffusing within the jet pipe 51 and being widely dispersed through the diffuser cover 56 below the jet pipe 51. This allows it to interact with the protective gas axially ejected from the nozzle 31. The shielding gas, combined with the shielding gas, fully covers the edge of the molten pool and the heat-affected zone (expanding the protection range by 40%), and can form a low-speed laminar flow (flow velocity 0.5~1.2m / s), preventing external air penetration. When the branch port 66 is connected to the lower row hole 65, the shielding gas is guided downward through the inner branch pipe 61 to form a high-speed concentrated jet. On the one hand, it can increase the welding penetration, and on the other hand, it can ensure that the shielding gas is fully concentrated at the weld pool. Especially in overhead welding, the shielding gas impacts the surface of the molten pool to form a spreading effect, thereby achieving high coverage and ensuring welding stability.

[0064] When the inner ring 6 is positioned between the upper row of holes 64 and the lower row of holes 65, the diversion port 66 can simultaneously connect with both the upper row of holes 64 and the lower row of holes 65. Therefore, a portion of the protective gas is sprayed upwards and diffused through the inner branch pipe 61, while another portion is sprayed downwards and upwards as a straight jet. Thus, the coupling of the high-energy jet and the low-speed diffusion field forms a fractal protective gas curtain with "center anchoring and edge buffering," resulting in a protective gas effectiveness of up to 88%, enhanced wind resistance, and suitability for various welding applications. In this process, the axial fine-tuning of the adjusting ring 57 can effectively change the effective flow area of ​​the diversion port 66 and the upper and lower row of holes 64 and 65, thereby adjusting the flow ratio of the protective gas entering the upper and lower row of holes 64 and changing the flow effect of the fractal protective gas curtain.

[0065] An adjusting ring 57 is rotatably connected to the upper part of the jet pipe 51. The adjusting ring 57 is sleeved on the outer side of the inner ring sleeve 6, and a guide pin is vertically fixed on the side wall of the inner ring sleeve 6. An inclined guide groove is opened on the inner wall of the adjusting ring 57, and the guide pin is slidably connected to the inclined guide groove.

[0066] The upper end of the jet pipe 51 is provided with a bidirectional motor 58. The output end of the bidirectional motor 58 is fixed to the adjusting ring 57. That is to say, under the action of forward and reverse rotation, the bidirectional motor 58 can drive the inner ring sleeve 6 to slide axially through the sliding action of the guide pin and the inclined guide groove, thereby changing the air supply mode of the protective gas unit 5 and realizing autonomous and flexible adjustment.

[0067] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. An industrial welding robot with gas protection, characterized in that: It includes: A fixed base (11) has a robotic arm (1) mounted on its upper surface via a waist joint turntable; A wrist actuator is installed at the end of the robotic arm (1), and a mounting shaft (12) is provided on the wrist actuator; A coupling frame (2) is fixed on a mounting shaft (12). A welding gun device (3) is mounted below the coupling frame (2). A nozzle (31) is provided at the lower end of the welding gun device (3). The wire feed tube (4) is fixed to one side of the welding torch device (3) by a clamp (34); The protective gas unit (5) is inclinedly installed on one side of the nozzle (31) of the welding torch device (3). The nozzle (31) is coaxially fixed with an airflow sleeve (32), and an airflow hole (33) is opened on the side wall of the nozzle (31) at the airflow sleeve (32). The airflow hole (33) is connected to the protective gas unit (5). The protective gas unit (5) includes: The jet pipe (51) has an extension plate (52) fixed to its outer wall. The extension plate (52) has an air passage (53) that communicates with the airflow hole (33). The jet pipe (51) has an air hole (511) that is sealed and connected to the air passage (53). The inner ring sleeve (6) is coaxially arranged inside the jet pipe (51), and the inner branch pipe (61) is fixed in the center of the jet pipe (51); A sealing ring sleeve (62) is slidably sleeved outside the inner branch pipe (61). The inner wall of the inner ring sleeve (6) is provided with an annular guide cavity (63), and the sealing ring sleeve (62) is provided with a fixed annular cavity (621). Multiple reinforcing rods (54) are circumferentially fixed between the annular guide cavity (63) and the fixed annular cavity (621). A channel (55) is formed in each of the aforementioned stiffeners (54), and the two ends of the channel (55) are respectively connected to the annular guide cavity (63) and the fixed annular cavity (621); The upper row of holes (64) and the lower row of holes (65) are distributed vertically and are opened on the side wall of the inner branch pipe (61). The inner wall of the sealing ring (62) is provided with a diversion port (66). A diffuser (56) is fixed to the lower end of the jet pipe (51); The inner ring sleeve (6) is slidably connected to the jet pipe (51), and a straight groove (67) is provided on the outer wall of the inner ring sleeve (6), which is connected to the air hole (511). The inner branch pipe (61) is provided with an isolation rib between the upper row of holes (64) and the lower row of holes (65). The isolation rib divides the interior of the inner branch pipe (61) into two independent channels. An air hood (68) is fixed at the upper end of the inner branch pipe (61). A diffuser plate (69) is fixed above the interior of the jet pipe (51).

2. The industrial welding robot with gas protection according to claim 1, characterized in that: The coupling frame (2) is constructed in an L-shape. A rotating shaft seat (21) is rotatably connected to the coupling frame (2). A coupling tube (22) is vertically fixed below the rotating shaft seat (21). A rotating shaft is rotatably connected inside the coupling tube (22). The other end of the coupling tube (22) is provided with a suspension plate (23) fixed to the rotating shaft, and the welding gun device (3) is fixed on the suspension plate (23).

3. The industrial welding robot with gas protection according to claim 1, characterized in that: The wire feeding tube (4) is rotatably connected to a wire guide wheel (41), and a fixed paste tube (42) is provided inside the wire feeding tube (4) below the wire guide wheel (41). A bypass channel (43) is radially opened on the side wall of the fixed paste tube (42), and a paste feeding tube (44) is sealed and connected to the side wall of the wire feeding tube (4). The paste feeding tube (44) is connected to the bypass channel (43). Inside the wire feeding tube (4), at the upper and lower ends of the fixed paste tube (42), respectively, there are flow-stopping sleeves (45).

4. An industrial welding robot with gas protection according to claim 3, characterized in that: The paste delivery tube (44) is externally connected to a flexible tube, and alloy paste is delivered inside the flexible tube.

5. An industrial welding robot with gas protection according to claim 1, characterized in that: One end of the extension plate (52) is connected and fixed to the nozzle (31), and the air hole (511) is connected to the air flow hole (33) through the air passage (53). The jet pipe (51) is inclined downward toward the nozzle (31).

6. An industrial welding robot with gas protection according to claim 1, characterized in that: The diffuser plate (69) has an arc-shaped cross-section, and its center is located above the diffuser plate (69).

7. An industrial welding robot with gas protection according to claim 1, characterized in that: During the process of the sealing ring (62) sliding up and down synchronously with the inner ring (6), the diversion port (66) is simultaneously connected to the upper row hole (64) and the lower row hole (65), or connected to one of them individually.

8. An industrial welding robot with gas protection according to claim 1, characterized in that: An adjusting ring (57) is rotatably connected to the upper part of the jet pipe (51). The adjusting ring (57) is sleeved on the outside of the inner ring sleeve (6), and a guide pin is vertically fixed on the side wall of the inner ring sleeve (6). An inclined guide groove is opened on the inner wall of the adjusting ring (57), and the guide pin is slidably connected to the inclined guide groove. The upper end of the jet pipe (51) is provided with a bidirectional motor (58), and the output end of the bidirectional motor (58) is fixed to the regulating ring (57).

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