CN113399792B

CN113399792B - High-precision laser recognition device and method for welding

Info

Publication number: CN113399792B
Application number: CN202110765760.1A
Authority: CN
Inventors: 郭家友; 王继文; 侯克文; 王伟昌
Original assignee: Anhui Gongbu Zhizao Industrial Technology Co ltd
Current assignee: Anhui Gongbu Zhizao Industrial Technology Co ltd
Priority date: 2021-07-08
Filing date: 2021-07-08
Publication date: 2022-09-09
Anticipated expiration: 2041-07-08
Also published as: CN113399792A

Abstract

The invention relates to the technical field of welding, in particular to a high-precision laser recognition device and a method for welding, wherein the device comprises the following steps: the invention discloses a welding device, a clamp, a sensor unit, a protective cover and a shielding part, wherein the sensor unit is arranged on one side of the welding device through the clamp, a welding torch is arranged at the lower end of the welding device, a welding wire is arranged at the lower end of the welding torch, a workpiece is arranged at the lower end of the welding wire, the sensor unit comprises a containing box, a gas supply port, a first connecting terminal, a second connecting terminal, a light-transmitting plate, a light projection part, a detection part and a first gas flow path, the gas supply port, the first connecting terminal and the second connecting terminal are arranged at the upper end of the containing box, and the arrangement of the sealing plate, the back plate and the shielding cover enables the cleaning nozzle at the bottom surface of the protective cover to reciprocate up and down, and the gas sprayed from the second gas spraying port washes and cools the bottom of the protective cover, and simultaneously improves the stability of the gas pressure in the shielding cover.

Description

High-precision laser recognition device and method for welding

Technical Field

The invention relates to the field of welding, in particular to a high-precision laser recognition device and method for welding.

Background

Conventionally, when welding such as butt welding is performed by arc welding or the like on a pair of workpieces such as iron plates having a groove shape, a welding torch is brought close to (a portion of the workpieces in the groove shape of butt welding). In this state, a voltage is applied between the tip of the welding wire fed from the welding torch and the workpiece, and an arc is generated therebetween. By this, the welding wire is melted, the workpieces are heated and melted, and the workpieces can be welded to each other.

When welding, the distance between the welding torch and the workpiece or the shape of the workpiece affects the welding quality of the workpiece, so in the welding process of the prior art, a sensor is needed to measure the distance between the welding torch and the workpiece or the shape of the workpiece, the measurement accuracy of the sensor may be affected if heat generated by welding is transmitted to the sensor, spatter generated by welding may shield the sensor, and the measurement of the sensor is inaccurate, the prior art also adopts a shielding component to shield the heat and the spatter, but the shielding component needs to be replaced frequently, is time-consuming and labor-consuming, and often needs to use shielding gas in the welding process, the shielding gas can absorb a large amount of heat released by welding in the welding process, so that energy consumed in the welding process cannot completely act on the welding wire and the workpiece, and wastes a large amount of energy, these problems in the field of soldering are urgently in need of improvement.

Disclosure of Invention

Accordingly, the present invention has been made in view of the above problems, and it is an object of the present invention to provide a high-precision laser recognition apparatus and method for welding, which can solve the problems that heat and spatter generated during welding affect the measurement precision of a sensor, the service life of a shielding member is not long, and replacement is not required frequently, and welding consumes a large amount of energy using a shielding gas.

A high-precision laser recognition device for welding, comprising: welding set, anchor clamps, the sensor unit, the visor, the shielding part, the sensor unit passes through anchor clamps and installs in welding set's one side, welding set's lower extreme is equipped with the welding torch, the lower extreme of welding torch is equipped with the welding wire, the lower extreme of welding wire is equipped with the work piece, the sensor unit is including holding the box, gaseous supply port, connecting terminal one, connecting terminal two, the light-passing board, light projecting part, the detection part, first gas flow path, the upper end that holds the box is equipped with gaseous supply port, connecting terminal one, connecting terminal two, the inside that holds the box is equipped with light projecting part and detection part, the lower extreme that holds the box is equipped with two light-passing boards, the below that holds the box is equipped with the visor, the inside of holding the box is run through and is equipped with first gas flow path, the visor includes: laser jet-out mouth, the laser receiving port, the installation department, the gaseous flow path of second, a supporting seat, the sprocket, the impeller, the below of the right-hand member of visor is equipped with the installation department, the inside of visor is equipped with the gaseous flow path of second, the lower extreme in the gaseous flow path of second has been seted up laser jet-out mouth and laser receiving port, the right side upper end and the left side lower extreme of visor all are equipped with the supporting seat, the upper end of left side supporting seat is equipped with impeller one, the coaxial fixed sprocket one that is equipped with in upper end of impeller one, the lower extreme of right side supporting seat is equipped with impeller two, the coaxial fixed sprocket two that is equipped with in upper end of impeller two, the occlusion part includes: the back plate is arranged on one side of the shielding cover, the transmission cam is arranged at the lower end of the shielding cover, the transmission cam and the impeller are coaxially and fixedly arranged, the protective cover bottom surface cleaning device is arranged on one side, close to the back plate, of the shielding cover, and the shielding surface cleaning device is arranged on one side, far away from the back plate, of the shielding cover.

Preferably, a projection device is provided on one side of the light projection unit, a laser light source is provided above the light projection unit, a light receiving device is provided on the detection unit, and a detection device is provided above the detection unit.

Preferably, the first gas flow path communicates with the second gas flow path.

Preferably, the impeller II is an axial flow wind wheel, and the chain wheel I is in transmission connection with the chain wheel II through a chain.

Preferably, the back plate is provided with a vertical groove, the surface of the transmission cam is provided with a track, and the lower end of the transmission cam is coaxially provided with a first bevel gear.

Preferably, the shielding surface cleaning device includes: bevel gear two, rotatory trachea, shelter from the face and wash the shower nozzle, rotatory trachea is established in one side of occlusion part, and rotatory trachea one end is equipped with bevel gear two with bevel gear one looks meshing, and rotatory trachea's the other end is equipped with shelters from the face and washs the shower nozzle, and rotatory trachea's upper end just is located the air inlet of having seted up of occlusion part one, shelters from the face and washs the shower nozzle and has seted up air jet one near the lateral surface of occlusion part.

Preferably, the cleaning device for the bottom surface of the protective cover comprises: closing plate, pull rod, visor bottom surface washing shower nozzle, the vertical slip setting of pull rod is in the inside that shelters from the lid, and the lower extreme of pull rod just is located and shelters from the inside closing plate that is equipped with of lid, and the outside vertical slip of backplate is provided with visor bottom surface washing shower nozzle.

Preferably, a cam ejector pin is fixedly arranged at the upper end of the pull rod and arranged in the track, a second air inlet is formed in the surface of the pull rod, a second air jet is formed in the surface of the cleaning sprayer at the bottom of the protective cover, and a vertical sliding block is arranged in a vertical groove.

A method of a high-precision laser recognition device for welding comprises the following steps:

s1: during welding, a voltage is applied between the tip of a welding wire fed from a welding torch and a workpiece, thereby generating an arc therebetween;

s2: the welding wire is melted, a molten pool is generated on the workpiece, and the workpiece can be welded; a welding device is moved from right to left to form a weld (bead) between the workpieces;

s3: the shielding part shields splashed objects which splash out of the molten pool and face the side surface below the containing box, and gas is introduced into the gas supply port and flows into the protective cover;

s4: the first impeller is coaxially and fixedly provided with a first chain wheel, the upper end of a channel of the mounting part is provided with a second impeller, the second impeller is an axial flow wind wheel, the second impeller rotates to generate downward airflow, the downward airflow is input into the shielding part through the mounting part, the second impeller is coaxially and fixedly provided with a second chain wheel, and the first chain wheel and the second chain wheel are in chain transmission; the second impeller drives the transmission cam to rotate;

S5: the shielding surface cleaning nozzle is enabled to rotationally spray gas to clean welding spatters left on the shielding surface, the discharged gas is slowly discharged to the vicinity of a welding area to be used as welding shielding gas, and the shielding gas is preheated by the protective cover and the shielding part, so that heat loss during welding can be reduced, and welding efficiency is improved;

s6: the cleaning nozzle on the bottom surface of the protective cover moves up and down in a reciprocating manner, and the gas ejected from the gas ejection port II washes and cools the bottom of the protective cover, so that the measurement accuracy of the sensor unit is ensured.

The invention has the following beneficial effects:

1. the transmission arrangement among the impeller, the chain wheel and the chain wheel of the invention enables the kinetic energy of the gas input into the second gas flow path from the first gas flow path to be converted into the mechanical energy of the rotation of the impeller, and in the case where the laser emitting port and the laser receiving port are open, the air pressure input from the shielding portion inside the protective cover can be increased, and drives the component in the shielding part to rotate, so that the shielding surface cleaning nozzle can rotate to spray gas to clean welding spatters left on the shielding surface, and the discharged gas is slowly discharged to the vicinity of the welding area to be used as welding shielding gas, the shielding gas is preheated by the protective cover and the shielding part, so that the heat loss during welding can be reduced, the welding efficiency is improved, the cleaning nozzle on the bottom surface of the protective cover reciprocates up and down, and the gas sprayed from the gas nozzle washes and cools the bottom of the protective cover, and the measurement accuracy of the sensor unit is ensured.

2. According to the invention, the sealing plate, the back plate and the shielding cover are arranged, so that the cleaning nozzle on the bottom surface of the protective cover reciprocates up and down, and the shielding cover still keeps sealed while the gas ejected from the gas ejection opening II washes and cools the bottom of the protective cover, thereby improving the stability of the gas pressure in the shielding cover.

Drawings

Fig. 1 is a plan view schematically illustrating the overall structure of the present invention.

Fig. 2 is a perspective view of the overall structure of the present invention.

Fig. 3 is a schematic structural view of the sensor unit, the protective cover, and the shielding portion of the present invention.

Fig. 4 is a schematic diagram of the internal structure of the sensor unit and the protective cover of the present invention.

Fig. 5 is a schematic view of the internal structure of the shielding portion of the present invention.

FIG. 6 is a schematic structural diagram of a cleaning device for the bottom surface of a protective cover according to the present invention.

Fig. 7 is a schematic view of the detailed structure of the lower end of the back plate of the present invention.

Wherein: 1. a welding device; 2. a clamp; 3. a sensor unit; 4. a protective cover; 5. a shielding portion; 11. a welding torch; 12. welding wires; 31. accommodating the box; 32. a gas supply port; 33. a first connecting terminal; 34. a second connecting terminal; 35. a light-transmitting plate; 36. a light projecting section; 37. a detection unit; 38. a first gas flow path; 361. a projection device; 362. a laser light source; 371. a light receiving device; 372. a detection device; 41. a laser emitting port; 42. a laser receiving port; 43. an installation part; 44. a second gas flow path; 45. a supporting seat; 46a, a first chain wheel; 46b and a second chain wheel; 47a, an impeller I; 47b, impeller two; 51. a shielding cover; 52. a back plate; 53. a drive cam; 54. a shielding surface cleaning device; 55. a protective cover bottom surface cleaning device; 521. a vertical slot; 531. a track; 532. a first bevel gear; 541. a second bevel gear; 542. rotating the air pipe; 543. the shielding surface is used for cleaning the spray head; 5421. a first air inlet; 5431. a first air jet; 551. sealing plates; 552. a pull rod; 553. cleaning the spray head on the bottom surface of the protective cover; 5521. a cam thimble; 5522. a second air inlet; 5523. connecting blocks; 5531. and a second gas nozzle.

Detailed Description

Preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings, so that those embodiments can be easily implemented by those having ordinary skill in the art to which the present invention pertains. However, the present invention may be embodied in many different forms and is not limited to the embodiments described below. In addition, in order to more clearly describe the present invention, components not connected to the present invention will be omitted from the drawings.

As shown in fig. 1, a high-precision laser recognition apparatus for welding includes: the welding device 1, the clamp 2, the sensor unit 3, the protective cover 4 and the shielding part 5;

as shown in fig. 1, the sensor unit 3 according to the present embodiment is attached to the welding apparatus 1 by a jig 2; welding wire 12 is supplied to welding torch 11 of welding apparatus 1; during welding, a voltage is applied between the tip of the welding wire 12 fed from the welding torch 11 and the workpiece W, thereby generating an arc therebetween; by this, the welding wire 12 is melted to generate a molten pool P in the workpiece W, and the workpiece W can be welded; a weld pool P is formed on the work W, and the welding device 1 is moved from right to left to form a weld (weld bead) B between the works W; in fig. 1, the workpiece W is conveniently depicted as one workpiece, but two or more workpieces are butt-welded, fillet-welded, lap-welded, and the like. The welding method is not particularly limited. In the present embodiment, the welding of the workpieces is defined as arc welding using the welding wire 12, and may be other welding such as TIG welding, electron beam welding, laser beam welding, and gas welding;

In order to stably weld the workpiece W by the welding apparatus 1, it is important to measure the distance between the welding torch 11 and the workpiece W or the shape of the workpiece W. Here, in the present embodiment, as an example, the shape of the workpiece W or the distance to the workpiece W is measured by the sensor unit 3.

As shown in fig. 1, 2, 3, and 4, the sensor unit 3 includes: a container case 31, a gas supply port 32, a first connection terminal 33, a second connection terminal 34, a transparent plate 35, a light projecting section 36, a detecting section 37, and a first gas flow path 38; the sensor unit 3 is a device that measures the shape of the workpiece W or the distance to the workpiece W (from the sensor unit 3) by the detected laser light (detection light); the light projecting section 36 projects laser light toward the surface of the welding workpiece W, and the detecting section 37 detects the laser light reflected from the surface of the welding workpiece W, and the light projecting section 36 includes: a laser light source 362 that generates laser light; a projection device (optical system) 361 for projecting the laser light generated by the laser light source 362 toward the workpiece W;

the detection unit 37 includes: a light receiving device 371 that receives the laser light reflected by the surface of the workpiece W; and a detection device 372, the detection device 372 detects the laser light sent from the light receiving device 371; the light receiving device 371 transmits the received laser light reflected by the surface of the workpiece W to the detecting device 372; a detection device 372, for example, an imaging device (camera), which detects laser light reflected by the workpiece surface W and transmits data of the detected laser light to an image processing device (not shown) provided outside or inside the sensor device; the image processing device measures the shape (state) of the workpiece W or the distance from the sensor unit 3 (specifically, the laser light source 362) to the workpiece W, and for example, the image processing device converts the distance between the welding torch 11 and the workpiece W based on the measured distance;

As shown in fig. 1, 2, 3, and 4, the housing box 31 is configured to house the light projecting section 36 and the detecting section 37 and to allow passage of the projected laser light emitted from the light projecting section 36 and the laser light reflected from the surface of the workpiece W toward the detecting section 37; a light-transmitting plate 35 made of a material (for example, transparent resin, glass, or the like) through which the projected laser light and the reflected laser light can pass, if the light-transmitting plate can pass, for example, the light-transmitting plate may be in an open state; in the present embodiment, a transparent plate 35 through which the projected laser light and the reflected laser light can pass is provided below the storage box 31, and a protective cover 4 is provided below the storage box 31;

as shown in fig. 5, a first gas flow path 38 for flushing communicating with the protective cover 4 is formed in the housing case 31; examples of the gas supplied to the first gas flow path 38 include air (atmospheric air), helium, argon, nitrogen, carbon dioxide, and a mixed gas of these gases; a gas having chemical stability with respect to the welded portion of the work W, i.e., a gas that can be used as a shielding gas for welding;

as shown in fig. 1, 2, 3, and 4, the accommodating case 31 has, on its upper surface: a connection terminal one 33 for outputting a detection signal of the sensor unit 3 and the like; and a second connection terminal 34 for supplying power to the sensor unit 3 and inputting a control signal and the like to the sensor unit 3; further, a gas supply port 32 is provided on the upper surface of the housing case 31, and the gas supply port 32 supplies gas to the protective cover 4 through the first gas flow path 38; further, on the upper surface of the housing box 31, there are provided display lamps (not shown) for displaying the states of power-on, power-off, etc. of the sensor unit 3;

As shown in fig. 1, 2, 3, and 4, the protective cover 4 includes: a laser emitting port 41, a laser receiving port 42, a mounting portion 43, a second gas flow path 44, a support base 45, a sprocket 46, and an impeller 47; the protective cover 4 is made of, for example, a metal material or a resin material, and is attached from the bottom surface side of the storage case 31 by a fastener such as a screw. By mounting the protective cover 4 to the housing box 31, a second gas flow path 44 communicating with the first gas flow path 38 is formed. A laser emitting port 41 and a laser receiving port 42 formed in the second gas flow path 44; the laser emitting port 41 and the laser receiving port 42 are openings, the airflow in the second gas flow path 44 can flow out from the laser emitting port 41 and the laser receiving port 42 to flush away smoke on the laser propagation path, and the airflow ejected from the laser receiving port 42 can flush the surface of the shielding part 5 facing the bottom of the protective cover 4, so as to improve the heat dissipation efficiency; as shown in fig. 4, a mounting portion 43 is disposed below the right end of the protection cover 4 for fixedly mounting the shielding portion 5, and a channel is formed in the mounting portion 43 and is respectively communicated with the protection cover 4 and the shielding portion 5; a first impeller 47a which can be driven by airflow is arranged at the communication part of the first air flow passage 38 and the second air flow passage 44, the structure of the first impeller 47a can be exemplified by an axial flow wind wheel or a wind power generation wind wheel, the first impeller 47a is coaxially and fixedly provided with a chain wheel 46a, the upper end of the passage of the mounting part 43 is provided with a second impeller 47b, the second impeller 47b is an axial flow wind wheel, the second impeller 47b rotates to generate downward airflow, the downward airflow is input into the shielding part 5 through the mounting part 43, the second impeller 47b is coaxially and fixedly provided with a chain wheel 46b, the first impeller 47a and the second impeller 47b are both rotatably arranged on a supporting seat 45 fixedly arranged in the protective cover 4, and the chain wheel 46a and the chain wheel 46b are in chain transmission;

As shown in fig. 1 to 7, the shielding portion 5 includes: a shielding cover 51, a back plate 52, a transmission cam 53, a shielding surface cleaning device 54 and a protective cover bottom surface cleaning device 55; the shielding cover 51 is a cuboid hollow shell, a back plate 52 is arranged in the position facing the bottom surface of the protective cover 4, and the back plate 52 is fixedly arranged in the position facing the bottom surface of the protective cover 4 of the shielding cover 51; a vertical groove 521 is formed in the back plate 52; the transmission cam 53 and the second impeller 47b are coaxially and fixedly arranged, the transmission cam 53 and the second impeller 47b coaxially rotate, a track 531 is arranged on the surface of the transmission cam 53, a first bevel gear 532 is coaxially and fixedly arranged at the lower end of the transmission cam 53, and the shielding surface cleaning device 54 is rotatably arranged in the middle of a main shielding surface of the shielding part 5 in a penetrating manner;

the mask cleaning device 54 includes: the rotating air pipe 542 is rotatably arranged in the middle of a main shielding surface of the shielding part 5 in a penetrating mode, the bevel gear II 541 in meshing transmission with the bevel gear I532 is coaxially and fixedly arranged at one end, located inside the shielding part 5, of the rotating air pipe 542, an air inlet I5421 is formed in the portion, located inside the shielding part 5, of the rotating air pipe 542, the air inlet I5421 is used for inputting air to the shielding surface cleaning device 54, the shielding surface cleaning nozzle 543 is communicated and arranged at one end, located outside the shielding part 5, of the rotating air pipe 542, the surface, close to the main shielding surface of the shielding part 5, of the shielding surface cleaning nozzle 543 is provided with an air outlet I5431, the rotation of the bevel gear I532 can drive the shielding surface cleaning nozzle 543 to rotatably eject welding spatters left on the shielding surface, and discharged air is slowly discharged to the vicinity of a welding area to serve as welding protection air, the shielding gas is preheated by the protective cover 4 and the shielding part 5, so that the heat loss during welding can be reduced, and the welding efficiency is improved;

The protective cover bottom surface cleaning device 55 includes: a sealing plate 551, a pull rod 552, and a cleaning nozzle 553 at the bottom of the protective cover; the area of the sealing plate 551 is approximately equal to the bottom area of the shielding cover 51, the sealing plate 551 is vertically slidably disposed inside the shielding cover 51, the pull rod 552 is vertically slidably disposed inside the shielding cover 51, the upper end of the pull rod 552 is fixedly provided with a cam thimble 5521, the cam thimble 5521 is disposed in the track 531 of the transmission cam 53, the transmission cam 53 drives the cam thimble 5521 to reciprocate up and down when rotating, and further drives the pull rod 552 to reciprocate up and down, the surface of the pull rod 552 is provided with a second air inlet 5522, the second air inlet 5522 is used for inputting air to the protective cover bottom surface cleaning device 55, the outer side of the back plate 52 is vertically slidably provided with a protective cover bottom surface cleaning nozzle 553, the connecting block 5523 disposed at the lower end of the pull rod 552 is communicated with the protective cover bottom surface cleaning nozzle 553, the surface of the protective cover bottom surface cleaning nozzle 553 is provided with a second air outlet 5531 relative to the bottom surface of the protective cover 4, the cleaning nozzle 553 on the bottom surface of the protective cover reciprocates up and down and the second gas jet port 5531 jets gas to wash and cool the bottom of the protective cover 4, so that the measurement accuracy of the sensor unit 3 is ensured, the connecting block 5523 is vertically and slidably arranged in the vertical groove 521 of the back plate 52, the sealing plate 551 is fixedly connected with the lower end of the pull rod 552, a certain gap is reserved between the lower end of the back plate 52 and the bottom surface of the shielding cover 51, and the gap is used for stabilizing the air pressure between the bottom surface of the sealing plate 551 and the bottom surface of the shielding cover 51; when the pull rod 552 moves upward, the sealing plate 551 moves upward, and the interior of the shielding cover 51 can be sealed.

s1: during welding, a voltage is applied between the tip of a welding wire 12 fed from a welding torch 11 and a workpiece W, thereby generating an arc therebetween;

s2: the welding wire 12 melts to generate a molten pool P on the workpiece W, so that the workpiece W can be welded; a weld pool P is formed on the work W, and the welding device 1 is moved from right to left to form a weld (weld bead) B between the works W;

s3: a shield portion 5 for shielding the splashed material splashed from the molten pool P toward the lower side surface of the storage box 31, and for introducing gas into the gas supply port 32 so that the gas flows into the protective cover 4;

s4: the first impeller 47a is driven by airflow, a first chain wheel 46a is coaxially and fixedly arranged on the first impeller 47a, a second impeller 47b is arranged at the upper end of a channel of the mounting portion 43, the second impeller 47b is an axial-flow wind wheel, the second impeller 47b can generate downward airflow when rotating, the downward airflow can be input into the shielding portion 5 through the mounting portion 43, a second chain wheel 46b is coaxially and fixedly arranged on the second impeller 47b, and the first chain wheel 46a and the second chain wheel 46b are in chain transmission; the second impeller 47b drives the transmission cam 53 to rotate;

s5: the shielding surface cleaning nozzle 543 is rotated to spray gas to clean welding spatter left on the shielding surface, and the discharged gas is slowly discharged to the vicinity of a welding area to be used as welding shielding gas, and the shielding gas is preheated by the protective cover 4 and the shielding part 5, so that heat loss during welding can be reduced, and welding efficiency is improved;

S6: the cleaning nozzle 553 at the bottom of the protective cover reciprocates up and down and the second gas nozzle 5531 ejects gas to wash and cool the bottom of the protective cover 4, thereby ensuring the measurement accuracy of the sensor unit 3.

Claims

1. A high-precision laser recognition device for welding, comprising: the welding device comprises a welding device (1), a clamp (2), a sensor unit (3), a protective cover (4) and a shielding part (5); the method is characterized in that: the sensor unit (3) is installed on one side of the welding device (1) through a clamp (2), a welding torch (11) is arranged at the lower end of the welding device (1), a welding wire (12) is arranged at the lower end of the welding torch (11), a workpiece (W) is arranged at the lower end of the welding wire (12), the sensor unit (3) comprises a containing box (31), a gas supply port (32), a first connecting terminal (33), a second connecting terminal (34), a light transmitting plate (35), a light projecting part (36), a detection part (37) and a first gas flow path (38), the upper end of the containing box (31) is provided with the gas supply port (32), the first connecting terminal (33) and the second connecting terminal (34), the light projecting part (36) and the detection part (37) are arranged inside the containing box (31), the two light transmitting plates (35) are arranged at the lower end of the containing box (31), a protective cover (4) is arranged below the containing box (31), the inside of the containing box (31) is provided with a first gas flow path (38) in a penetrating way, and the protective cover (4) comprises: the laser irradiation device comprises a laser irradiation hole (41), a laser receiving hole (42), a mounting part (43), a second gas flow path (44), a supporting seat (45), a chain wheel (46) and an impeller (47), wherein the mounting part (43) is arranged below the right end of the protective cover (4), the second gas flow path (44) is arranged inside the protective cover (4), the first gas flow path (38) is communicated with the second gas flow path (44), the laser irradiation hole (41) and the laser receiving hole (42) are arranged at the lower end of the second gas flow path (44), the supporting seats (45) are arranged at the upper end of the right side and the lower end of the left side of the protective cover (4), a first impeller (47 a) is arranged at the upper end of the supporting seat (45) on the left side, a first chain wheel (46 a) is coaxially and fixedly arranged at the upper end of the first impeller (47 a), a second impeller (47 b) is arranged at the lower end of the supporting seat (45) on the right side, the upper end of the second impeller (47 b) is coaxially and fixedly provided with a second chain wheel (46 b), and the shielding part (5) comprises: shelter from lid (51), backplate (52), transmission cam (53), shelter from face belt cleaning device (54), visor bottom surface belt cleaning device (55), one side of sheltering from lid (51) is equipped with backplate (52), the lower extreme of sheltering from lid (51) is equipped with transmission cam (53), and transmission cam (53) and two (47 b) coaxial fixed settings of impeller, one side that shelter from lid (51) is close to backplate (52) is equipped with visor bottom surface belt cleaning device (55), one side that shelter from lid (51) and keep away from backplate (52) is equipped with shelter from face belt cleaning device (54), shelter from face belt cleaning device (54) and include: bevel gear two (541), rotatory trachea (542), shelter from face and wash shower nozzle (543), establish in one side of occlusion part (5) rotatory trachea (542), the one end of rotatory trachea (542) is equipped with bevel gear two (541) with bevel gear (532) engaged with, and the other end of rotatory trachea (542) is equipped with shelters from face and washs shower nozzle (543), the upper end of rotatory trachea (542) just is located one side surface of occlusion part (5) and has seted up air inlet one (5421), shelter from face and wash shower nozzle (543) and seted up air jet one (5431) near occlusion part (5), visor bottom surface belt cleaning device (55) include: sealing plate (551), pull rod (552), visor bottom surface washing shower nozzle (553), pull rod (552) vertical sliding setting are in the inside of sheltering from lid (51), the lower extreme of pull rod (552) just is located shelter from lid (51) inside and be equipped with sealing plate (551), the vertical sliding in outside of backplate (52) is provided with visor bottom surface washing shower nozzle (553), the fixed cam thimble (5521) that is provided with in upper end of pull rod (552), cam thimble (5521) set up in track (531), and air inlet two (5522) have been seted up on the surface of pull rod (552), and connecting block (5523) that the lower extreme of pull rod (552) was equipped with, jet orifice two (5531) have been seted up on the surface of visor bottom surface washing shower nozzle (553), connecting block (5523) vertical sliding setting is in vertical groove (521).

2. The high-precision laser recognition device for welding according to claim 1, wherein: a projection device (361) is arranged on one side of the light projection part (36), and a laser light source (362) is arranged above the light projection part (36).

3. The high-precision laser recognition device for welding according to claim 1, wherein: the top of detection portion (37) is equipped with light-receiving device (371), the top of detection portion (37) is equipped with detection device (372).

4. The high-precision laser recognition device for welding according to claim 1, wherein: the second impeller (47 b) is an axial flow wind wheel, and the first chain wheel (46 a) is in transmission connection with the second chain wheel (46 b) through a chain.

5. The high-precision laser recognition device for welding according to claim 1, wherein: the back plate (52) is provided with a vertical groove (521), the surface of the transmission cam (53) is provided with a track (531), and the lower end of the transmission cam (53) is coaxially provided with a first bevel gear (532).

6. The use method of the high-precision laser recognition device for high welding according to any one of claims 1 to 5, comprising the steps of:

S1: during welding, a voltage is applied between the tip of a welding wire (12) fed from a welding torch (11) and a workpiece (W), thereby generating an arc therebetween;

s2: the welding wire (12) is melted to generate a molten pool P on the workpiece (W), and the workpiece (W) can be welded; a welding device (1) is moved from right to left with a molten pool P formed on the work (W) to form a welded portion between the works (W);

s3: a shielding part (5) which shields the splashed objects which are splashed out of the molten pool P and face the lower side surface of the containing box (31), and simultaneously gas is introduced into the gas supply port (32) and flows into the protective cover (4);

s4: the air flow driven impeller I (47 a), the impeller I (47 a) is coaxially and fixedly provided with a chain wheel I (46 a), the upper end of a channel of the mounting part (43) is provided with an impeller II (47 b), the impeller II (47 b) is an axial flow wind wheel, the impeller II (47 b) can generate downward air flow when rotating, the downward air flow can be input into the shielding part (5) through the mounting part (43), the impeller II (47 b) is coaxially and fixedly provided with a chain wheel II (46 b), and the chain wheel I (46 a) and the chain wheel II (46 b) are in chain transmission; the second impeller (47 b) drives the transmission cam (53) to rotate;

S5: the shielding surface cleaning nozzle (543) is enabled to rotationally spray gas to clean welding spatters left on the shielding surface, the discharged gas is slowly discharged to the vicinity of a welding area to be used as welding shielding gas, and the shielding gas is preheated by the protective cover (4) and the shielding part (5), so that heat loss during welding can be reduced, and welding efficiency is improved;

s6: the cleaning nozzle (553) on the bottom surface of the protective cover reciprocates up and down, and the gas ejected from the gas ejection opening II (5531) washes and cools the bottom of the protective cover (4), so that the measurement accuracy of the sensor unit (3) is ensured.