Back atmosphere protection device suitable for tailored blank laser welding
By designing a back atmosphere protection device with three-stage atmosphere treatment zone and extruded partitioned mesh output, the problem of lack of atmosphere protection on the back of metal parts during laser deep melt welding is solved, and the welding quality is improved and the effect of "single-side welding, double-side forming" is achieved.
Patent Information
- Application Number
- CN202421608531.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-09
- Publication Date
- 2025-04-25
- Estimated Expiration
- 2034-07-09
AI Technical Summary
During the laser deep melt welding process, the back of the metal parts lacks effective atmosphere protection, resulting in defects such as oxidation, pores and inclusions of the weld, reducing the mechanical properties of the weld.
A back atmosphere protection device including a U-shaped exhaust top plate, a W-shaped gas separation plate, a bottom plate, a double limit groove side plate and an F-type end cover is designed. Through the three-stage atmosphere treatment area and an extruded partitioned mesh output design, a uniform and stable inert atmosphere protection for the welding area is achieved.
It effectively avoids the pores and oxidation defects caused by air injection on the back of metal parts during welding, improves the welding quality of laser welding, and achieves the effect of "single-side welding and double-side forming".
Smart Images
Figure CN222790877U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of structure design and application of a laser welding auxiliary device, in particular to a back atmosphere protection device suitable for laser welding. Background Art
[0002] In recent years, laser welding technology has been widely used in many fields such as aerospace, automobiles, ships, and machinery. Laser welding technology uses the excellent directionality and high power density of laser beams to work. The laser beam is focused through an optical system to form a highly concentrated heat source radiation zone on the surface of the workpiece to be processed in a very short time, so that the welded workpiece melts rapidly and quickly forms a firm weld point and weld. It is a thermal radiation processing method that achieves hot and cold alternation in a very short time. As an important part of laser welding technology, laser welding technology can weld several metal materials of different thicknesses and different coatings to form a whole plate, profile, etc. to meet the different requirements of parts for material properties. Compared with traditional welding technology, laser welding technology has the advantages of fast speed, high energy density, small deformation, and small heat-affected zone. It can optimize the structure, lighten the equipment, and increase the flexibility of product design. In particular, it can achieve the advantages of "single-sided welding and double-sided forming" in the state of laser deep melting welding. And in order to obtain high-quality welds in laser welding, atmosphere protection is particularly critical. In the process of deep-melting laser welding, high-energy laser beam can easily break through the phase change threshold of the welded metal, realizing the "keyhole effect" in deep-melting welding. The laser entering the keyhole fully utilizes the laser energy through reflection in the hole, forms molten pool stirring in the dynamic welding process, and quickly cools and forms after laser scanning. In this process, if there is no reasonable atmosphere protection on the back of the workpiece material, it is easy to be invaded by air, causing weld oxidation, a large number of pores and inclusions inside the weld, and other defects, which significantly reduce the mechanical properties of the weld area of the formed organization. Therefore, the back atmosphere protection of laser welding is particularly important. Traditional atmosphere protection is to blow air to the back organization in one direction through a straight tube with holes. Its characteristics are that the gas volume is the largest at the input end of the protective gas, and gradually weakens along the direction of the weld. It cannot ensure the stable and uniform output of the airflow along the length of the weld, and it is easy to cause local air turbulence near the weld, resulting in defects such as oxidation and loose pores.
[0003] People are eager to obtain a back atmosphere protection device suitable for laser welding with excellent technical effect. Utility Model Content
[0004] The utility model provides a back atmosphere protection device suitable for laser tailoring welding; it is particularly suitable for the anti-oxidation atmosphere protection of the back tissue forming of "single-sided welding and double-sided forming" of plate-type metal parts in the form of tailoring welding under the state of laser deep melting welding.
[0005] The technical solution of the utility model is:
[0006] A back atmosphere protection device suitable for laser welding is placed on the back of a metal part during the laser welding process; the key technical features are:
[0007] The back atmosphere protection device suitable for laser welding comprises a U-shaped exhaust top plate 101, a W-shaped gas distribution plate 102, a bottom plate 103, a double-limiting groove side plate 104, a double-limiting groove side plate 2 105, an F-shaped end cover 106, and an F-shaped end cover 2 107; wherein:
[0008] The entire back atmosphere protection device suitable for laser welding is a rectangular parallelepiped structure with a cavity inside; in the length direction, the U-shaped exhaust top plate 101, the bottom plate 103, the double limit groove side plate 104, and the double limit groove side plate 2 105 are respectively arranged in the upper, lower, left, and right directions of the entire back atmosphere protection device suitable for laser welding, and the W-shaped gas distribution plate 102 is arranged in the cavity surrounded by the aforementioned U-shaped exhaust top plate 101, the bottom plate 103, the double limit groove side plate 104, and the double limit groove side plate 2 105; the F-shaped end cover 106 and the F-shaped end cover 2 107 for sealing the internal cavity of the entire back atmosphere protection device suitable for laser welding are respectively arranged at both ends in the length direction;
[0009] The U-shaped exhaust top plate 101 is located at the upper part of the entire device. The two side edges of the U-shaped exhaust top plate 101 in the length direction are respectively matched and connected with the upper limit groove 208 arranged on the inner side of the double limit groove side plate 104 and the double limit groove side plate 105 through clearance fit. The two side edges of the W-shaped gas distributor 102 in the length direction are respectively matched and connected with the middle limit groove 209 arranged on the inner side of the double limit groove side plate 104 and the double limit groove side plate 105 through clearance fit; the two ends of the bottom plate 103 are respectively connected with the limit grooves below the F-type end cover 106 and the F-type end cover 2 107 through clearance fit, and are connected and fixed; finally, the double limit groove side plate 104 and the double limit groove side plate 105 are respectively bonded to the corresponding connections of the bottom plate 103, the F-type end cover 106 and the F-type end cover 2 107 with epoxy resin adhesive as a whole;
[0010] Gas flow channels are provided on the U-shaped exhaust top plate 101 and the W-shaped gas distribution plate 102 .
[0011] The back atmosphere protection device suitable for laser welding described in the utility model preferably claims the following technical contents:
[0012] The back atmosphere protection device suitable for laser welding is provided with a three-level atmosphere treatment area, so as to facilitate the layered treatment of the protective gas and create a high-quality anti-oxidation atmosphere environment for the whole process of back tissue welding; wherein: the primary and secondary protective gas storage chambers realize the storage and slow release of the gas and the uniform extrusion output, and the final output area directly acts on the back of the laser welded metal to create a micro-positive pressure inert atmosphere environment, providing high-quality dynamic inert atmosphere protection for the whole process of laser welding;
[0013] The cross-sectional shape of the W-shaped air distributor 102 is "W"-shaped: an inner annular channel 201 perpendicular to its cross-sectional shape is arranged at its lower part, a narrow slit air inlet 203 is arranged between the lower part of the inner annular channel 201 near the bottom plate 103 and the inner side surface of the bottom plate 103, and an annular protective air inlet 301 arranged on the F-shaped end cover 106 is connected to the upstream of the inner annular channel 201, and the W-shaped air distributor 102, the bottom plate 103 and the double limit groove side plate 106 on the left and right sides below the narrow slit air inlet 203 are connected to the W-shaped air distributor 102, the bottom plate 103 and the double limit groove side plate 106. 104, the local space between the double limit groove side plate 105 is the primary double triangle protective gas storage chamber 202; the primary double triangle protective gas storage chamber 202 is a left-right symmetrical structure; the two primary double triangle protective gas storage chambers 202 on the left and right sides are connected to the internal annular channel 201 through the narrow slit air inlet 203; the primary double triangle protective gas storage chamber 202 can provide a slow release space for the protective gas, so that the input gas can obtain sufficient buffering and make it relatively evenly distributed so as to diffuse to the lower-level space;
[0014] The cavity between the double-limiting groove side plate 1 104, the double-limiting groove side plate 2 105, the F-type end cover 1 106, the F-type end cover 2 107, the U-shaped exhaust top plate 101, and the W-shaped gas distribution plate 102 is the secondary protective gas storage chamber 205;
[0015] The side of the U-shaped exhaust top plate 101 away from the W-shaped gas distributor plate 102 is the final protection gas output area.
[0016] In the back atmosphere protection device suitable for laser welding, the angle between the two wings of the W-shaped gas distributor 102 and the bottom plate 103 is 30° to 50°. It is further preferably 40°. A large angle design is used here to maximize the capacity of the primary gas storage space while ensuring the rationality of the device. The triangular space design fully complies with the basic principles of aerodynamics and fluid mechanics, and can maximize the internal circulation, buffering and accumulation of the protective gas in the primary environment;
[0017] In the back atmosphere protection device suitable for laser welding, the gas flow channel provided on the U-shaped exhaust top plate 101 is the annular exhaust port 206;
[0018] There are multiple annular exhaust ports 206, all of which are arranged at the bottom of the U-shaped exhaust top plate 101 near the central part and form a hole array structure; there are 2 to 4 annular exhaust ports 206 in each horizontal row; the aperture of the annular exhaust ports 206 is 0.5 to 12 mm; in the longitudinal direction, the hole spacing between two adjacent annular exhaust ports 206 is 0.5 to 5 times the hole diameter.
[0019] Further preferably: in the back atmosphere protection device suitable for laser welding, the gas flow channel provided on the W-shaped gas distribution plate 102 is a ring-shaped exhaust port 204;
[0020] The annular exhaust port 204 is disposed at the edge closest to both sides of the W-shaped gas distributor plate 102;
[0021] On the single side edge of the W-shaped gas distributor 102, 1 to 4 annular exhaust ports 204 are arranged in each row in the horizontal direction; the aperture of the annular exhaust ports 204 is 1 to 20 mm; in the longitudinal direction, the hole spacing between two adjacent annular exhaust ports 204 is 0.3 to 3 times of the hole diameter.
[0022] The annular protective gas inlet 301 is arranged on the main part of the F-type end cover 106 perpendicular to the length direction of the back atmosphere protection device suitable for laser welding, and the hole axis of the annular protective gas inlet 301 is parallel to the length direction of the back atmosphere protection device suitable for laser welding;
[0023] The cross section of the annular protective gas inlet 301 is circular, and the hole diameter is 4-6 mm.
[0024] The F-type end cap 106 and the F-type end cap 2 107 in the length direction are both inverted "F"-shaped structures, and the lower part thereof is provided with a countersunk threaded hole 302 that matches the bottom plate 103, and the countersunk threaded hole 302 is equipped with a countersunk screw that is convenient for fixing the F-type end cap 106 and the F-type end cap 2 107 to the bottom plate 103 respectively;
[0025] The double-limit groove side plate 1 104 and the double-limit groove side plate 2 105 are provided with a connecting threaded opening 303 for easy connection and fixing.
[0026] When multiple back atmosphere protection devices suitable for laser welding are used in combination, a connecting plate 401 arranged between two adjacent back atmosphere protection devices suitable for laser welding and between the double limit groove side panels 104 or the double limit groove side panels 105 on the two adjacent back atmosphere protection devices suitable for laser welding is also provided; the connecting plate 401 is provided with connecting threaded openings 402 and matching connecting screws which are respectively connected to each double limit groove side panel 104 or the double limit groove side panel 105.
[0027] Two annular exhaust ports 204 are arranged in each row on the single-side edge of the W-shaped gas distributor 102; the aperture of the annular exhaust ports 204 is 1.5-5 mm; in the longitudinal direction, the hole spacing between two adjacent annular exhaust ports 204 is 0.4-0.6 times the hole diameter.
[0028] The annular exhaust ports 206 arranged on the U-shaped exhaust top plate 101 are arranged in three rows in the cross-sectional direction perpendicular to the length direction of the entire back atmosphere protection device suitable for laser welding; the aperture of the annular exhaust ports 206 is 1 to 3 mm; in the longitudinal direction, the hole spacing between two adjacent annular exhaust ports 206 is 0.5 to 2 times the hole diameter.
[0029] After the gas in the primary gas storage chamber accumulates and generates a certain pressure, it is pressed into the secondary protective gas storage chamber 205 through the symmetrically distributed annular exhaust port 1 204 and released. A pair of air holes are arranged at an interval of 5mm on each side, and the axial direction of the air holes is perpendicular to the two wings of the W-shaped air distributor 102, which can ensure that the shielding gas accumulated in the primary air storage chamber is output obliquely upward and evenly mixed in the secondary shielding gas storage chamber, and further slow down the gas, so that the input gas reaches a stable and uniform state in the layer area. After the pressure accumulates to a certain extent, the uniform and stable shielding gas is squeezed and output vertically upward through the annular exhaust port 206 to reach the final shielding gas output area 207, forming a local inert gas cloud in the back protection area of the metal plate to be welded. After filling, it provides uniform atmosphere protection for the back tissue forming of the metal part. By buffering and releasing the pressure of the circulation of welding shielding gas layer by layer, combined with the extrusion-type partitioned mesh output design, compared with the traditional direct blowing method, the atmosphere protection area is expanded, and the air flow disorder and turbulence caused by excessive or uneven shielding gas flow rate are reduced, and the defects such as pores and oxidation caused by air entrainment in the molten pool on the back of the metal part during welding are avoided, which can better achieve the "single-sided welding, double-sided forming" effect under the laser deep melting welding state.
[0030] The beneficial effects of the utility model are:
[0031] The utility model buffers and releases the flow of welding shielding gas layer by layer, cooperates with the extrusion-type partitioned mesh output design, and realizes spatial uniform distribution of shielding gas through a reasonably designed hierarchical gas buffer space, and outputs it evenly and stably to the back of the part, reducing turbulence, meeting the requirements of the back of the workpiece for oxygen-free stable atmosphere protection during laser welding, and effectively improving the welding quality of laser welding "single-sided welding, double-sided forming". The utility model can effectively meet the application requirements of laser welding technology and has a good back atmosphere protection effect; it has a simple structure, strong operability, and excellent comprehensive technical effects. BRIEF DESCRIPTION OF THE DRAWINGS
[0032] Figure 1This is an exploded view of the back atmosphere protection device suitable for laser welding described in Example 1;
[0033] Figure 2 This is a cross-sectional view of the back atmosphere protection device suitable for laser welding described in Example 1;
[0034] Figure 3 It is a partial enlarged view of the F-type end cover 106 at the end of the back atmosphere protection device suitable for laser welding;
[0035] Figure 4 A schematic structural diagram of two back atmosphere protection devices suitable for laser welding connected as one body by a connecting plate 401;
[0036] Figure 5 It is a schematic diagram of the local structure of the top view of the U-shaped exhaust top plate 101;
[0037] Figure 6 It is a schematic diagram of the partial structure of the axonometric view of the W-shaped gas distributor 102;
[0038] Figure 7 It is a simplified diagram of the end structure of the W-shaped gas distributor plate 102. DETAILED DESCRIPTION
[0039] The present invention will be further described below in conjunction with the embodiments and drawings of the specification, but is not limited thereto.
[0040] Example 1
[0041] A back atmosphere protection device suitable for laser welding; a back atmosphere protection device suitable for laser welding, such as Figure 1 to Figure 7 As shown; it is placed on the back of the metal parts during the laser welding process; it is particularly suitable for the anti-oxidation atmosphere protection of the back structure formation of sheet metal parts in the form of welding under the laser deep melting welding state to achieve "single-sided welding, double-sided forming".
[0042] The technical solution of this embodiment is:
[0043] A back atmosphere protection device suitable for laser welding is placed on the back of a metal part during laser welding; the back atmosphere protection device suitable for laser welding comprises a U-shaped exhaust top plate 101, a W-shaped air distribution plate 102, a bottom plate 103, a double-limiting groove side plate 104, a double-limiting groove side plate 2 105, an F-shaped end cover 106, and an F-shaped end cover 2 107; wherein:
[0044] The entire back atmosphere protection device suitable for laser welding is a rectangular parallelepiped structure with a cavity inside; in the length direction, the U-shaped exhaust top plate 101, the bottom plate 103, the double limit groove side plate 104, and the double limit groove side plate 2 105 are respectively arranged in the upper, lower, left, and right directions of the entire back atmosphere protection device suitable for laser welding, and the W-shaped gas distribution plate 102 is arranged in the cavity surrounded by the aforementioned U-shaped exhaust top plate 101, the bottom plate 103, the double limit groove side plate 104, and the double limit groove side plate 2 105; the F-shaped end cover 106 and the F-shaped end cover 2 107 for sealing the internal cavity of the entire back atmosphere protection device suitable for laser welding are respectively arranged at both ends in the length direction;
[0045] The U-shaped exhaust top plate 101 is located at the upper part of the entire device. The two side edges of the U-shaped exhaust top plate 101 in the length direction are respectively matched and connected with the upper limit groove 208 arranged on the inner side of the double limit groove side plate 104 and the double limit groove side plate 105 through clearance fit. The two side edges of the W-shaped gas distributor 102 in the length direction are respectively matched and connected with the middle limit groove 209 arranged on the inner side of the double limit groove side plate 104 and the double limit groove side plate 105 through clearance fit; the two ends of the bottom plate 103 are respectively connected with the limit grooves below the F-type end cover 106 and the F-type end cover 2 107 through clearance fit, and are connected and fixed; finally, the double limit groove side plate 104 and the double limit groove side plate 105 are respectively bonded to the corresponding connections of the bottom plate 103, the F-type end cover 106 and the F-type end cover 2 107 with epoxy resin adhesive as a whole;
[0046] Gas flow channels are provided on the U-shaped exhaust top plate 101 and the W-shaped gas distribution plate 102 .
[0047] The back atmosphere protection device suitable for laser welding is provided with a three-level atmosphere treatment area, so as to facilitate the layered treatment of the protective gas and create a high-quality anti-oxidation atmosphere environment for the whole process of back tissue welding; wherein: the primary and secondary protective gas storage chambers realize the storage and slow release of the gas and the uniform extrusion output, and the final output area directly acts on the back of the laser welded metal to create a micro-positive pressure inert atmosphere environment, providing high-quality dynamic inert atmosphere protection for the whole process of laser welding;
[0048] The cross-sectional shape of the W-shaped air distributor 102 is "W"-shaped: an inner annular channel 201 perpendicular to its cross-sectional shape is arranged at its lower part, a narrow slit air inlet 203 is arranged between the lower part of the inner annular channel 201 near the bottom plate 103 and the inner side surface of the bottom plate 103, and an annular protective air inlet 301 arranged on the F-shaped end cover 106 is connected to the upstream of the inner annular channel 201, and the W-shaped air distributor 102, the bottom plate 103 and the double limit groove side plate 106 on the left and right sides below the narrow slit air inlet 203 are connected to the W-shaped air distributor 102, the bottom plate 103 and the double limit groove side plate 106. 104, the local space between the double limit groove side plate 105 is the primary double triangle protective gas storage chamber 202; the primary double triangle protective gas storage chamber 202 is a left-right symmetrical structure; the two primary double triangle protective gas storage chambers 202 on the left and right sides are connected to the internal annular channel 201 through the narrow slit air inlet 203; the primary double triangle protective gas storage chamber 202 can provide a slow release space for the protective gas, so that the input gas can obtain sufficient buffering and make it relatively evenly distributed so as to diffuse to the lower-level space;
[0049] The cavity between the double-limiting groove side plate 1 104, the double-limiting groove side plate 2 105, the F-type end cover 1 106, the F-type end cover 2 107, the U-shaped exhaust top plate 101, and the W-shaped gas distribution plate 102 is the secondary protective gas storage chamber 205;
[0050] The side of the U-shaped exhaust top plate 101 away from the W-shaped gas distributor plate 102 is the final protection gas output area.
[0051] In the back atmosphere protection device suitable for laser welding, the angle between the two wings of the W-shaped gas distributor 102 and the bottom plate 103 is 30° to 50°. The optimal angle is 40°. A large angle design is used here to maximize the capacity of the primary gas storage space while ensuring the rationality of the device. The triangular space design fully complies with the basic principles of aerodynamics and fluid mechanics, and can maximize the internal circulation, buffering and accumulation of the protective gas in the primary environment;
[0052] In the back atmosphere protection device suitable for laser welding, the gas flow channel provided on the U-shaped exhaust top plate 101 is the annular exhaust port 206;
[0053] There are multiple annular exhaust ports 206, all of which are arranged at the bottom of the U-shaped exhaust top plate 101 near the central part and form a hole array structure; there are 2 to 4 annular exhaust ports 206 in each horizontal row; the aperture of the annular exhaust ports 206 is 0.5 to 12 mm; in the longitudinal direction, the hole spacing between two adjacent annular exhaust ports 206 is 0.5 to 5 times the hole diameter.
[0054] In the back atmosphere protection device suitable for laser welding, the gas flow channel provided on the W-shaped gas distribution plate 102 is a ring-shaped exhaust port 204;
[0055] The annular exhaust port 204 is disposed at the edge closest to both sides of the W-shaped gas distributor plate 102;
[0056] On the single side edge of the W-shaped gas distributor 102, 1 to 4 annular exhaust ports 204 are arranged in each row in the horizontal direction; the aperture of the annular exhaust ports 204 is 1 to 20 mm; in the longitudinal direction, the hole spacing between two adjacent annular exhaust ports 204 is 0.3 to 3 times of the hole diameter.
[0057] The annular protective gas inlet 301 is arranged on the main part of the F-type end cover 106 perpendicular to the length direction of the back atmosphere protection device suitable for laser welding, and the hole axis of the annular protective gas inlet 301 is parallel to the length direction of the back atmosphere protection device suitable for laser welding;
[0058] The cross section of the annular protective gas inlet 301 is circular, and the hole diameter is 4-6 mm.
[0059] The F-type end cap 106 and the F-type end cap 2 107 in the length direction are both inverted "F"-shaped structures, and the lower part thereof is provided with a countersunk threaded hole 302 that matches the bottom plate 103, and the countersunk threaded hole 302 is equipped with a countersunk screw that is convenient for fixing the F-type end cap 106 and the F-type end cap 2 107 to the bottom plate 103 respectively;
[0060] The double-limit groove side plate 1 104 and the double-limit groove side plate 2 105 are provided with a connecting threaded opening 303 for easy connection and fixing.
[0061] When multiple back atmosphere protection devices suitable for laser welding are used in combination, a connecting plate 401 arranged between two adjacent back atmosphere protection devices suitable for laser welding and between the double limit groove side panels 104 or the double limit groove side panels 105 on the two adjacent back atmosphere protection devices suitable for laser welding is also provided; the connecting plate 401 is provided with connecting threaded openings 402 and matching connecting screws which are respectively connected to each double limit groove side panel 104 or the double limit groove side panel 105.
[0062] Two annular exhaust ports 204 are arranged in each row on the single-side edge of the W-shaped gas distributor 102; the aperture of the annular exhaust ports 204 is 1.5-5 mm; in the longitudinal direction, the hole spacing between two adjacent annular exhaust ports 204 is 0.4-0.6 times the hole diameter.
[0063] The annular exhaust ports 206 arranged on the U-shaped exhaust top plate 101 are arranged in three rows in the cross-sectional direction perpendicular to the length direction of the entire back atmosphere protection device suitable for laser welding; the aperture of the annular exhaust ports 206 is 1 to 3 mm; in the longitudinal direction, the hole spacing between two adjacent annular exhaust ports 206 is 0.5 to 2 times the hole diameter.
[0064] After the gas in the primary gas storage chamber accumulates and generates a certain pressure, it is pressed into the secondary protective gas storage chamber 205 through the symmetrically distributed annular exhaust port 1 204 and released. A pair of air holes are arranged at an interval of 5mm on each side, and the axial direction of the air holes is perpendicular to the two wings of the W-shaped air distributor 102, which can ensure that the shielding gas accumulated in the primary air storage chamber is output obliquely upward and evenly mixed in the secondary shielding gas storage chamber, and further slow down the gas, so that the input gas reaches a stable and uniform state in the layer area. After the pressure accumulates to a certain extent, the uniform and stable shielding gas is squeezed and output vertically upward through the annular exhaust port 206 to reach the final shielding gas output area 207, forming a local inert gas cloud in the back protection area of the metal plate to be welded. After filling, it provides uniform atmosphere protection for the back tissue forming of the metal part. By buffering and releasing the pressure of the circulation of welding shielding gas layer by layer, combined with the extrusion-type partitioned mesh output design, compared with the traditional direct blowing method, the atmosphere protection area is expanded, and the air flow disorder and turbulence caused by excessive or uneven shielding gas flow rate are reduced, and the defects such as pores and oxidation caused by air entrainment in the molten pool on the back of the metal part during welding are avoided, which can better achieve the "single-sided welding, double-sided forming" effect under the laser deep melting welding state.
[0065] This embodiment buffers and releases the pressure of the welding shielding gas layer by layer, cooperates with the extrusion-type partitioned mesh output design, and uses a reasonably designed hierarchical gas buffer space to achieve spatial uniform distribution of the shielding gas, and outputs it evenly and stably to the back of the part, reducing turbulence. This meets the requirement of the back of the workpiece for inert stable atmosphere protection during laser welding, and effectively improves the welding quality of "single-sided welding, double-sided forming" in laser welding.
Claims
1. A back atmosphere protection device suitable for laser welding, which is placed on the back of a metal part during the laser welding process; characterized in that: The back atmosphere protection device suitable for laser welding comprises a U-shaped exhaust top plate (101), a W-shaped air distribution plate (102), a bottom plate (103), a first double-limiting groove side plate (104), a second double-limiting groove side plate (105), a first F-shaped end cover (106), and a second F-shaped end cover (107); wherein: The entire back atmosphere protection device suitable for laser welding is a rectangular parallelepiped structure with a cavity arranged inside; in the length direction, the U-shaped exhaust top plate (101), the bottom plate (103), the double limit groove side plate one (104), and the double limit groove side plate two (105) are respectively arranged in the upper, lower, left, and right directions of the entire back atmosphere protection device suitable for laser welding, and the W-shaped gas distribution plate (102) is arranged in the cavity surrounded by the aforementioned U-shaped exhaust top plate (101), the bottom plate (103), the double limit groove side plate one (104), and the double limit groove side plate two (105); the F-shaped end cover one (106) and the F-shaped end cover two (107) for sealing the internal cavity of the entire back atmosphere protection device suitable for laser welding are respectively arranged at both ends in the length direction; The U-shaped exhaust top plate (101) is located at the upper part of the entire device. The two side edges of the U-shaped exhaust top plate (101) in the length direction are respectively connected with the upper end limit groove 1 (208) arranged on the inner side surface of the double limit groove side plate 1 (104) and the double limit groove side plate 2 (105) through clearance fit. The two side edges of the W-shaped gas distribution plate (102) in the length direction are respectively connected with the upper end limit groove 1 (208) arranged on the inner side surface of the double limit groove side plate 1 (104) and the double limit groove side plate 2 (105) through clearance fit. 05) the middle limiting groove 2 (209) on the inner side surface is matched and connected; the two ends of the bottom plate (103) are respectively connected with the limiting grooves below the F-type end cover 1 (106) and the F-type end cover 2 (107) through clearance matching, and are connected and fixed; finally, the double limiting groove side plate 1 (104) and the double limiting groove side plate 2 (105) are respectively bonded with the bottom plate (103), the F-type end cover 1 (106), and the F-type end cover 2 (107) at the corresponding connection points with epoxy resin adhesive; Gas flow channels are provided on the U-shaped exhaust top plate (101) and the W-shaped gas distribution plate (102).
2. The back atmosphere protection device suitable for laser welding according to claim 1, characterized in that: The back atmosphere protection device suitable for laser welding is provided with three-level atmosphere treatment zones; The cross-sectional shape of the W-shaped gas distributor (102) is "W"-shaped: an internal annular channel (201) perpendicular to its cross-sectional shape is arranged at its lower portion; a narrow slit air inlet (203) is arranged between the lower portion of the internal annular channel (201) near the bottom plate (103) and the inner side surface of the bottom plate (103); an annular protective gas inlet (301) arranged on the F-shaped end cover (106) is connected to the upstream of the internal annular channel (201); the local space between the W-shaped gas distributor (102), the bottom plate (103) and the double limit groove side plate (104) and the double limit groove side plate (105) on the left and right sides below the narrow slit air inlet (203) is a primary double triangular protective gas storage chamber (202); the primary double triangular protective gas storage chamber (202) is a left-right symmetrical structure; the two primary double triangular protective gas storage chambers (202) on the left and right sides are connected to the internal annular channel (201) through the narrow slit air inlet (203); The cavity between the double-limiting groove side plate 1 (104), the double-limiting groove side plate 2 (105), the F-type end cover 1 (106), the F-type end cover 2 (107), the U-shaped exhaust top plate (101), and the W-shaped gas distribution plate (102) is a secondary protective gas storage chamber (205); The side of the outer side of the U-shaped exhaust top plate (101) away from the W-shaped gas distribution plate (102) is the final protection gas output area.
3. The back atmosphere protection device suitable for laser welding according to claim 2, characterized in that: In the back atmosphere protection device suitable for laser welding, the angle between the two wings of the W-shaped gas distribution plate (102) and the bottom plate (103) is 30° to 50°.
4. The back atmosphere protection device suitable for laser welding according to claim 3, characterized in that: In the back atmosphere protection device suitable for laser welding, the gas flow channel arranged on the U-shaped exhaust top plate (101) is an annular exhaust port 2 (206); There are a plurality of annular exhaust ports 2 (206) which are all arranged at the bottom of the U-shaped exhaust top plate (101) near the central part and form a hole array structure; there are 2 to 4 annular exhaust ports 2 (206) in each horizontal row; the hole diameter of the annular exhaust ports 2 (206) is 0.5 to 12 mm; in the longitudinal direction, the hole spacing between two adjacent annular exhaust ports 2 (206) is 0.5 to 5 times the hole diameter.
5. The back atmosphere protection device suitable for laser welding according to claim 3, characterized in that: In the back atmosphere protection device suitable for laser welding, the gas flow channel arranged on the W-shaped gas distribution plate (102) is an annular exhaust port 1 (204); The annular exhaust port 1 (204) is arranged at the position closest to the two side edges of the W-shaped gas distribution plate (102); One to four annular exhaust ports (204) are arranged in each row on a single side edge of the W-shaped gas distribution plate (102); the diameter of the annular exhaust ports (204) is 1 to 20 mm; in the longitudinal direction, the hole spacing between two adjacent annular exhaust ports (204) is 0.3 to 3 times the hole diameter.
6. The back atmosphere protection device suitable for laser welding according to claim 3, characterized in that: The annular protective gas inlet (301) is arranged on the main part of the F-shaped end cover (106) perpendicular to the length direction of the back atmosphere protection device suitable for laser welding, and the hole axis of the annular protective gas inlet (301) is parallel to the length direction of the back atmosphere protection device suitable for laser welding; The cross section of the annular protective gas inlet (301) is circular, and the hole diameter is 4-6 mm.
7. The back atmosphere protection device for laser welding according to any one of claims 2 to 6, characterized in that: The F-type end cover 1 (106) and the F-type end cover 2 (107) in the length direction are both inverted "F"-shaped structures, and the lower part thereof is provided with a countersunk threaded hole (302) matched with the bottom plate (103), and the countersunk threaded hole (302) is equipped with a countersunk screw for fixing the F-type end cover 1 (106) and the F-type end cover 2 (107) to the bottom plate (103) respectively; A connecting threaded opening 1 (303) for easy connection and fixing is arranged on the double-limiting groove side plate 1 (104) and the double-limiting groove side plate 2 (105).
8. The back atmosphere protection device suitable for laser welding according to claim 7, characterized in that: When a plurality of back atmosphere protection devices suitable for laser welding are used in combination, a connecting plate (401) arranged between the double limit groove side plate 1 (104) or the double limit groove side plate 2 (105) on the two adjacent back atmosphere protection devices suitable for laser welding is also provided between the two adjacent back atmosphere protection devices suitable for laser welding; the connecting plate (401) is provided with connecting threaded opening 2 (402) and matching connecting screws respectively connected to each double limit groove side plate 1 (104) or the double limit groove side plate 2 (105).
9. The back atmosphere protection device suitable for laser welding according to claim 5, characterized in that: Two annular exhaust ports (204) are arranged in each row on a single side edge of the W-shaped gas distribution plate (102); the diameter of the annular exhaust ports (204) is 1.5 to 5 mm; in the longitudinal direction, the hole spacing between two adjacent annular exhaust ports (204) is 0.4 to 0.6 times the hole diameter.
10. The back atmosphere protection device suitable for laser welding according to claim 4, characterized in that: The annular exhaust ports 2 (206) provided on the U-shaped exhaust top plate (101) are arranged in a row of three in a cross-sectional direction perpendicular to the length direction of the entire back atmosphere protection device suitable for laser welding; the aperture of the annular exhaust ports 2 (206) is 1 to 3 mm; in the longitudinal direction, the hole spacing between two adjacent annular exhaust ports 2 (206) is 0.5 to 2 times the hole diameter.