A laser welding gas protection device

Abstract

The present invention relates to a laser welding gas protection device. It comprises a fixing frame, an air inlet pipe and a flow divider, wherein the fixing frame is fixedly connected to the flow divider and the laser welding device respectively, the flow divider has a top surface, a bottom surface, a center hole, an annular cavity and an air outlet, the center hole penetrates the top surface and the bottom surface of the flow divider, the annular cavity surrounds the center hole and is coaxially arranged with the center hole; the air inlet pipe introduces protective gas into the annular cavity, and the air outlet is evenly distributed at the bottom of the annular cavity; the annular cavity has an inner wall and an outer wall, and the inner wall and / or the outer wall have a conical wall surface that is small at the top and large at the bottom, guiding the protective gas to form a frustum-shaped protective gas block below the flow divider. The laser welding gas protection device of the present invention diffuses and blows the protective gas downward evenly and stably, and forms a large-scale, uniform and stable protective gas block around the laser welding position below the flow divider, thereby improving the protection range and protection effect, simplifying the welding process, and improving the welding efficiency.

Description

Technical Field

[0001] The invention relates to a protective device in a welding process, in particular to a laser welding gas protective device. Background Art

[0002] With the rapid development of the aerospace industry, in order to meet the weight requirements, there are more and more skeleton + skin products. The skin and skeleton are connected by welding, but the traditional welding process has a large heat input, the welded joint has a coarse microstructure, the overall performance of the joint is poor, and the deformation after welding is serious. Laser has attracted much attention due to its advantages such as high brightness, coherence, monochromaticity, and good directionality. In addition, laser welding has high energy density, small heat input, fast crystallization speed, fine weld grains, good mechanical properties of the welded joint and small deformation, making the development and application of laser welding equipment more and more extensive, and the welding area needs to be protected during the laser welding process.

[0003] Existing laser welding gas protection devices usually use the side blowing of inert gas to protect the welding area. For example, a Chinese patent with authorization announcement number CN211490094U discloses a half-axle gear end face sealing welding device, in which a gas nozzle is arranged to blow inert gas in a circular direction toward the laser welding position to cover the entire workpiece to be welded to ensure welding safety; another example is a Chinese patent with authorization announcement number CN212043126U discloses a laser welding protection device, in which a protection box that can be raised and lowered is arranged, the protection box is covered on the surface of the workpiece to be processed, and air is blown into the protection box through the air outlet pipe in the protection box to form an inert gas protection layer on the surface of the workpiece in the protection box.

[0004] However, the protection device using this type of protection has a small protection area and a single direction, and can only achieve effective protection for plane straight line welding or large-angle arc welding. In the process of broken line and small-angle arc welding, segmented welding is required, the programming is cumbersome, which seriously affects the welding efficiency, and the protection effect is poor. Summary of the invention

[0005] The object of the present invention is to provide a laser welding gas protection device to solve the problems of poor protection effect and low welding efficiency of the existing laser welding protection device.

[0006] To achieve the above-mentioned purpose, the laser welding gas protection device in the present invention adopts the following technical scheme: it includes a fixing frame, an air inlet pipe and a flow divider, the flow divider is fixedly connected to the fixing frame, the fixing frame is fixedly connected to the laser welding device so as to move synchronously with the laser welding device, the flow divider has a top surface, a bottom surface, a center hole, an annular cavity and an air outlet, the center hole passes through the top surface and the bottom surface of the flow divider so as to allow the laser of the laser welding device to pass through, the annular cavity surrounds the center hole and is coaxially arranged with the center hole; one end of the air inlet pipe is connected to a protective gas source, and the other end is connected to the annular cavity so as to supply the annular cavity with a protective gas. The protective gas is introduced into the annular cavity, and the air outlet is arranged on the bottom surface of the flow divider to connect the annular cavity with the outside world. The air outlet is evenly distributed in the annular area on the bottom surface of the flow divider with the central hole as the center; the air outlet is inclined away from the central hole from top to bottom; the annular cavity has an inner wall close to the central hole and an outer wall away from the central hole, and the inner wall and / or the outer wall has a conical wall surface, and the size of the conical wall surface gradually increases from top to bottom, which is used to guide the protective gas to move obliquely downward toward the periphery of the flow divider, so as to form a frustum-shaped protective gas block below the flow divider in combination with the annularly distributed air outlet.

[0007] Its beneficial effects are: a flow divider with an annular cavity is provided, and the protective gas blown out of the air inlet pipe is radially guided outward by the conical wall of the annular cavity which is small at the top and large at the bottom, and combined with the annularly distributed air outlet holes at the bottom of the annular cavity, the protective gas is evenly diffused and blown out in an annular shape, forming a large and stable protective gas block around the laser welding position below the flow divider, thereby improving the protection range and protection effect; at the same time, there is no need to perform segmented welding for special working conditions, which simplifies the welding process and improves welding efficiency.

[0008] Preferably, at least one diverter plate is provided in the annular cavity, and the diverter plate is arranged parallel to the bottom plate of the diverter body to divide the annular cavity into multiple layers of chambers. The diverter plate is arranged below the air inlet of the air inlet pipe, and diverter holes are provided on the diverter plate to connect the upper and lower adjacent chambers.

[0009] Its beneficial effect is that a diverter plate is arranged in the annular cavity parallel to the bottom plate, dividing the annular cavity into upper and lower multi-layer chambers, stabilizing and diffusing the protective gas blown out from the air inlet pipe multiple times, improving the uniformity and stability of the protective gas flow, and facilitating the control of the formation of the protective gas block.

[0010] Furthermore, the diverter body is a diverter hood, which is a frustum-shaped hood that is small at the top and large at the bottom. The diverter hood includes a central tube, an outer ring plate, a top plate and a bottom plate. The inner hole of the central tube forms a central hole. The outer ring plate is a conical sleeve that is small at the top and large at the bottom and / or the central tube is a conical sleeve that is small at the top and large at the bottom. The air outlet is arranged on the bottom plate, and the annular cavity is surrounded by the central tube, the outer ring plate, the top plate and the bottom plate.

[0011] Its beneficial effect is that the diverter hood surrounded by the central tube, the outer ring plate, the top plate and the bottom plate is used as the diverter body, and the tapered plate wall of the outer ring plate and / or the central tube which is small at the top and large at the bottom can directly form the tapered side wall of the annular cavity to achieve the guidance and diffusion of the protective airflow. The structure is simple, and no further processing of the side wall of the annular cavity is required, so it is easy to manufacture.

[0012] Preferably, the air inlet of the air inlet pipe is arranged on the outer side wall of the annular cavity, and the air inlet direction of the air inlet pipe and the air outlet direction of the air outlet are perpendicular to each other.

[0013] Its beneficial effect is that the air inlet direction of the air inlet pipe is arranged perpendicularly to the air outlet direction of the air outlet, thereby avoiding the protective gas flow from being blown out of the air outlet directly after being blown out of the air inlet pipe, ensuring the flow stabilization and diffusion effect of the annular cavity on the protective gas flow, and facilitating the stable and uniform diffusion of the protective gas flow.

[0014] Preferably, the flow divider is in the shape of a truncated cone.

[0015] The beneficial effect thereof is that it is easy to determine the range of the protective gas block formed below the flow divider.

[0016] Preferably, the air outlet holes are centered on the central hole and are evenly distributed on a plurality of concentric circles centered on the central hole.

[0017] The beneficial effect is that the gas outlet holes are evenly distributed on multiple concentric circles with the central hole as the center, which is beneficial to improving the gas uniformity of the formed protective gas block and expanding the effective protection area of ​​the protective gas block.

[0018] Preferably, the radial positions of the outlet holes and the diversion holes on the adjacent diversion plates are staggered and / or the radial positions of the diversion holes on the upper and lower adjacent diversion plates are staggered, so that the protective gas is stabilized and diffused when entering the lower chamber from the upper chamber and then transmitted downward.

[0019] Its beneficial effect is that the diverter holes and the air outlet holes are radially staggered with each other, so as to prevent the protective gas flow from entering the next layer of chamber through the diverter holes of the upper layer of diverter plate and then being blown out directly from the diverter holes or air outlet holes of the next layer, thereby ensuring the flow stabilization and diffusion effects of each layer of chamber and improving the uniformity, stability and coverage of the protective gas.

[0020] Preferably, the fixing frame includes a fixing plate and a fixing arm, the fixing plate is arranged at the upper end of the fixing frame, the fixing arm connects the fixing plate and the flow divider, and the fixing frame is fixedly connected to the laser welding device via the fixing plate.

[0021] The beneficial effect is that the laser welding device is installed reliably by using the fixed plate, and the fixed support arm fixedly connects the fixed plate and the flow divider, so that the laser welding device and the laser welding gas protection device move stably and synchronously, ensuring the welding protection effect.

[0022] Furthermore, there are two fixed arms, which are spaced apart on both sides of the air intake pipe. The extending direction of the fixed arms is parallel to the air intake pipe, and the air intake pipe is fixedly installed between the two fixed arms.

[0023] The beneficial effect is that the air intake pipe is extended and installed between two fixed support arms of the fixing frame, and the fixed support arms are used to protect the air intake pipe, thereby improving the assembly reliability of the device.

[0024] Furthermore, a mounting structure is provided on the fixing plate to be fixedly connected to the upper end of the air intake pipe, and the air intake pipe extends downward to be fixedly connected to the flow divider.

[0025] Its beneficial effect is that the upper end of the air intake pipe is fixedly connected to the fixing plate, and the lower end is fixedly connected to the distributor, thereby ensuring the stability and connection reliability of the air intake pipe during the synchronous movement of the laser welding gas protection device and the laser welding device. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic diagram of the three-dimensional structure of the laser welding gas protection device of the present invention.

[0027] Figure 2 It is a cross-sectional view of the flow divider of the present invention.

[0028] Figure 3 It is a schematic diagram of the working state of the fluid distributor of the present invention.

[0029] Figure 4 It is a schematic diagram of the working state of the laser welding gas protection device of the present invention.

[0030] In the figure: 1, workpiece; 2, flow divider; 3, air inlet pipe; 4, fixing frame; 41, fixing plate; 411, mounting boss; 42, fixing arm; 5, flow divider plate; 51, flow divider hole; 6, bottom plate; 61, air outlet hole; 7, center tube; 71, center hole; 8, laser welding device; 9, laser; 10, protective gas block; 11, outer ring plate; 12, top plate. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical scheme and advantages of the present invention clearer, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention, that is, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. The components of the embodiments of the present invention described and shown in the drawings herein can be arranged and designed in various different configurations.

[0032] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making creative work are within the scope of protection of the present invention.

[0033] It should be noted that relational terms such as "first" and "second" that may appear are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, terms such as "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device that includes a series of elements includes not only those elements, but also other elements that are not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by a sentence such as "comprises a..." does not exclude the existence of other identical elements in the process, method, article or device that includes the element.

[0034] The features and performance of the present invention are further described in detail below in conjunction with the embodiments.

[0035] The specific embodiment of the laser welding gas protection device of the present invention is as follows: Figure 1 As shown, the main structure of the laser welding gas protection device of this embodiment mainly includes a flow divider 2, an air intake pipe 3 and a fixing frame 4. The fixing frame 4 includes two fixed arms 42 and a fixing plate 41 fixedly connected to the flow divider 2. The fixing plate 41 is fixedly connected to the upper ends of the two fixed arms 42. A mounting boss 411 is also provided on the back of the fixing plate 41 for fixing the air intake pipe 3. The air intake pipe 3 extends downward between the two fixed arms 42 to fix the flow divider 2. The extension direction of the air intake pipe 3 is always kept parallel to the extension direction of the fixed arms 42.

[0036] In order to more intuitively express the embodiments of the present invention, refer to Figure 2 , Figure 3 , Figure 4As shown for explanation, the flow divider 2 is specifically a truncated cone-shaped flow divider cover, which is composed of a central tube 7, an outer ring plate 11, a top plate 12 and a bottom plate 6. The central tube 7 is located in the center of the flow divider cover, connecting the top plate 12 and the bottom plate 6. The inner hole thereof forms a central hole 71 that passes through the top plate 12 and the bottom plate 6 for the laser 9 emitted by the laser welding device 8 to pass through, so as to realize the laser 9 welding process. The outer ring plate 11 is a conical sleeve with a small upper part and a large lower part, which is coaxially arranged with the central tube 7.

[0037] Specifically, Figure 2 As shown, the inner wall of the central tube 7, the outer ring plate 11, the top plate 12 and the bottom plate 6 enclose an annular cavity of the shroud, the outer ring plate 11 has an air inlet connected to the air inlet pipe 3, the upper end of the air inlet pipe 3 is connected to the protective gas source (not shown in the figure), and the lower end is connected to the annular cavity through the air inlet on the outer ring plate 11, and the bottom plate 6 has an air outlet 61 connecting the annular cavity with the outside, and the air outlet 61 is evenly distributed on multiple circumferences with the central hole 71 as the center. The air inlet direction of the air inlet pipe 3 is perpendicular to the air outlet direction of the air outlet 61 to ensure the uniform diffusion of the air flow in the annular cavity and improve the air flow stability.

[0038] like Figure 3 As shown, the outer wall of the annular cavity (i.e., the inner wall of the outer ring plate 11) is a tapered wall surface whose size gradually increases from top to bottom, so as to guide the shielding gas to move obliquely downward toward the periphery of the flow divider 2, and cooperate with the annular evenly distributed gas outlet holes 61 to form a truncated cone-shaped shielding gas block 10 (see Figure 3 The shaded part shows the effective gas protection for the laser welding process.

[0039] In addition, a diverter plate 5 parallel to the bottom plate 6 is arranged in the annular cavity, and the diverter plate 5 divides the annular cavity into upper and lower multi-layer chambers. The diverter plate 5 is provided with diverter holes 51 connecting the upper and lower adjacent chambers. The diverter holes 51 are evenly distributed on multiple circles with the central hole 71 as the center. The radial positions of the diverter holes 51 and the air outlet 61 are staggered with each other to ensure that the protective gas is stabilized and diffused by the lower chamber before being transmitted downward, which further improves the uniformity, stability and coverage of the protective gas flow.

[0040] When the laser welding gas protection device described in the above embodiment is used, Figure 4 As shown, the laser 9 emitted by the laser welding device 8 passes through the central hole 71 of the distributor 2 to weld the workpiece 1, and a relatively large truncated cone-shaped protective gas block 10 is formed around the welding position below the distributor 2 (see Figure 3At the same time, the laser welding device 8 is rigidly connected and fixed to the flow divider 2 by the fixing frame 4, so that the flow divider 2 moves synchronously with the laser welding device 8, and then the protective gas block 10 formed under the flow divider 2 always moves synchronously with the laser 9, so as to realize effective synchronous protection of the welding position on the workpiece 1, improve the arbitrariness of the welding path, do not need to perform corresponding complex welding programming for special working conditions, simplify the welding process, and improve the laser welding efficiency and welding quality.

[0041] Of course, the laser welding gas protection device of the present invention is not limited to the above-described embodiments. This article also provides several other embodiments of the laser welding gas protection device based on the design concept of the present invention, as follows:

[0042] In other embodiments of the laser welding gas protection device, what is different from the above-mentioned embodiments is that the flow divider may not be a flow divider hood surrounded by multiple plates, but an overall block structure. By punching, grooving, etc. on the block structure to form the above-mentioned annular cavity, center hole, flow divider plate, air inlet, air outlet and other structures, it is possible to achieve stable and uniform diffusion of the protective gas and form a frustum-shaped protective gas block below the flow divider.

[0043] In other embodiments of the laser welding gas protection device, different from the above-mentioned embodiments, the inner wall of the annular cavity may also be a conical wall surface whose size gradually increases from top to bottom, and correspondingly, the center tube may also be a conical sleeve with a small top and a large bottom, so as to achieve the guiding effect of the protective gas flow.

[0044] In other embodiments of the laser welding gas protection device, the difference from the above embodiment is that the flow divider may not be in the shape of a truncated cone, but in the shape of a truncated cone formed by a multi-faceted cone.

[0045] In other embodiments of the laser welding gas protection device, unlike the above-mentioned embodiments, the air inlet of the air inlet pipe may not be arranged on the side wall of the annular cavity, but may be arranged on the top of the annular cavity. Correspondingly, the radial position of the air inlet is staggered with the radial position of the diversion hole or the air outlet below.

[0046] In other embodiments of the laser welding gas protection device, different from the above-mentioned embodiments, the fixed support frame may not be provided with a fixed support arm, a fixed plate and a mounting structure, but the manifold and the laser welding device may be directly fixedly connected by an integral fixed frame, so that the laser welding device and the laser welding gas protection device can move synchronously, and correspondingly, the air inlet pipe is separately provided outside the fixed frame.

[0047] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. The patent protection scope of the present invention shall be based on the claims. All equivalent structural changes made using the contents of the description and drawings of the present invention should also be included in the protection scope of the present invention.

Claims

1. A laser welding gas protection device, comprising a fixing frame and an air inlet pipe, wherein the fixing frame is used to be fixedly connected to the laser welding device so as to move synchronously with the laser welding device, and one end of the air inlet pipe is connected to a protective gas source, wherein: It also includes a flow divider, which is fixedly connected to the fixing frame, and has a top surface, a bottom surface, a center hole, an annular cavity and an air outlet, wherein the center hole passes through the top surface and the bottom surface for the laser of the laser welding device to pass through, and the annular cavity surrounds the center hole and is coaxially arranged with the center hole; The other end of the air inlet pipe is connected to the annular cavity so as to introduce protective gas into the annular cavity. The air outlet holes are arranged on the bottom surface of the flow divider so as to connect the annular cavity with the outside. The air outlet holes are evenly distributed in the annular area of ​​the bottom surface with the central hole as the center; the air outlet holes are inclined away from the central hole from top to bottom; The annular cavity has an inner wall close to the center hole and an outer wall away from the center hole, and both the inner wall and the outer wall have a conical wall surface, and the size of the conical wall surface gradually increases from top to bottom, and is used to guide the protective gas to move obliquely downward toward the periphery of the diverter flow body, so as to form a frustum-shaped protective gas block under the diverter flow body in combination with the annularly distributed air outlet holes; at least one diverter plate is arranged in the annular cavity, and the diverter plate is arranged parallel to the bottom plate to divide the annular cavity into multi-layer chambers, and the diverter plate is arranged below the air inlet of the air inlet pipe, and diverter holes are arranged on the diverter plate to connect the upper and lower adjacent chambers, and the radial positions of the diverter holes and the air outlet holes are staggered with each other, and the air inlet of the air inlet pipe is arranged on the outer wall of the annular cavity, and the air inlet direction of the air inlet pipe is perpendicular to the air outlet direction of the air outlet holes, and the air outlet holes are centered on the center hole and evenly distributed on multiple concentric circles with the center hole as the center.

2. The laser welding gas protection device according to claim 1 is characterized in that: The diverter body is a diverter cover, which is a frustum-shaped cone with a small top and a large bottom. The diverter cover includes a central tube, an outer ring plate, a top plate and a bottom plate. The inner hole of the central tube forms the central hole. The outer ring plate is a conical sleeve with a small top and a large bottom and the central tube is a conical sleeve with a small top and a large bottom. The air outlet is arranged on the bottom plate, and the annular cavity is surrounded by the central tube, the outer ring plate, the top plate and the bottom plate.

3. The laser welding gas protection device according to claim 1 is characterized in that: The flow divider is in the shape of a truncated cone.

4. The laser welding gas protection device according to claim 1 is characterized in that: The fixing frame includes a fixing plate and a fixing arm. The fixing plate is arranged at the upper end of the fixing frame. The fixing arm connects the fixing plate and the flow divider. The fixing frame is fixedly connected to the laser welding device via the fixing plate.

5. The laser welding gas protection device according to claim 4 is characterized in that: There are two fixed arms, which are arranged at intervals on both sides of the air intake pipe. The extending direction of the fixed arms is parallel to the air intake pipe, and the air intake pipe is fixedly installed between the two fixed arms.

6. The laser welding gas protection device according to claim 5 is characterized in that: The fixing plate is provided with a mounting structure to be fixedly connected with the upper end of the air intake pipe, and the air intake pipe extends downward to be fixedly connected with the flow divider.

Images