Laser molten pool gas protection device and protection method applied to track enhanced vehicle

Abstract

The application provides a laser molten pool gas protection device and method applied to a track enhanced vehicle. The laser molten pool gas protection device applied to the track enhanced vehicle comprises a base movable along a track and a protection cover installed on the base. The base is used for allowing a laser beam column to pass through and form a laser molten pool on a track operation surface. A cooling cavity and an inert gas cavity are arranged in parallel and are isolated from each other in the protection cover. Water inlet pipes and water outlet pipes that are communicated with the cooling cavity are arranged on the protection cover and are used for connecting a cooling machine. Air inlet pipes that are communicated with the inert gas cavity are arranged on the protection cover and are used for connecting inert gas bottles. An air outlet that is communicated with the inert gas cavity and is close to the laser molten pool is arranged at the bottom of the protection cover. The air outlet is consistent with the extension direction of the laser molten pool and is used for allowing the inert gas delivered to form a protective atmosphere that covers the laser molten pool. The protection cover is cooled while the laser device is synchronously moved along the track, and the protective atmosphere that covers the laser molten pool is formed and is high in sealing property.

Description

Technical Field

[0001] This invention relates to a track reinforcement vehicle, and more particularly to a laser molten pool gas protection device and a laser molten pool gas protection method applied to the track reinforcement vehicle. The protection device travels synchronously along the track with the track reinforcement vehicle and its laser head assembly, and sprays inert gas to protect the laser molten pool. Background Technology

[0002] A track strengthening vehicle is an integrated processing device used in rail transit to strengthen the surface of train tracks. Its core technology involves using a regularly arranged array of laser heads to emit laser beams onto the track surface coated with a special paint. The lasers alloy the paint with the track surface, thus strengthening the track surface. This track strengthening vehicle integrates a spraying unit, a laser unit, and a drying unit, and operates while traveling along the track.

[0003] Laser processing generates a large amount of heat in a short period of time. Under the influence of this heat, the special coating reacts with oxygen in the air, resulting in a large number of bubbles, cracks, and slag, which seriously affects the surface reinforcement effect of the track. Therefore, oxygen in the laser molten pool must be removed during laser processing to ensure the alloying effect.

[0004] In existing technologies, an inert gas is typically used to create a protective atmosphere around the laser cladding pool to block oxygen. For example, the invention patent publication number CN114045490A discloses a gas circulation device for laser cladding, relating to the field of laser cladding. This device includes a laser chamber and a laser cladding mechanism and a workpiece positioning mechanism installed inside the laser chamber. An inert gas delivery device is installed outside the laser chamber to deliver inert gas to the location of the laser cladding mechanism inside the chamber. The exhaust port of the heat exchanger at the top of the laser chamber is connected to the gas circulation device via a pipe. The gas circulation device is used to introduce gas from the lower interior of the laser chamber to ensure that the laser cladding operation is conducted in an inert protective atmosphere.

[0005] For example, the utility model patent with authorization announcement number CN202763282U discloses a special molten pool gas protection device for CO2 lasers, which includes a connecting sleeve, a length adjusting cylinder and a blowing head connected coaxially from top to bottom. A gas storage cavity is formed between the blowing head and the length adjusting cylinder, which can form a vertical protective gas curtain around the laser molten pool. A horizontal air inlet pipe connected to the gas storage cavity and an air inlet pipe that can blow the protective gas directly to the laser molten pool are provided on the blowing head.

[0006] It is evident that existing protective atmosphere formation methods mainly include beam jetting and spatial envelopment, but their direct application to rail reinforcement vehicles faces significant obstacles. Firstly, since the rail working surface, consisting of the top and inner surfaces that frequently contact train wheels, is roughly inverted L-shaped, the laser head assembly of the rail reinforcement vehicle needs to form a laser beam array covering this inverted L-shaped working surface and generate a laser molten pool of corresponding shape. Therefore, beam jetting is not suitable. Secondly, because the laser beam array travels along the rail surface as the rail reinforcement vehicle moves, the inert gas beam generated by beam jetting is prone to deviation due to inertia, leading to oxygen entering the inert gas beam. Spatial envelopment requires a closed, stationary environment to form a protective atmosphere, making it even more difficult to form and apply to a moving laser molten pool, and it is also more costly. Summary of the Invention

[0007] Given that existing methods for forming inert gas protective atmospheres for laser molten pools are difficult to apply to track reinforcement vehicles in motion, this invention provides a laser molten pool gas protection device for track reinforcement vehicles. This device can not only cover the laser molten pool with a shape consistent with the track working surface, but also travel synchronously along the track with the track reinforcement vehicle.

[0008] The technical solution adopted by the present invention to solve the above-mentioned technical problems is as follows: a laser molten pool gas protection device applied to a track-enhanced vehicle, comprising a base that can move along the track and a protective cover installed on the base, wherein the base allows a laser beam to pass through and form a laser molten pool on the track working surface;

[0009] The protective cover contains parallel, isolated cooling chambers and at least one inert gas chamber; the protective cover is provided with an inlet pipe and an outlet pipe communicating with the cooling chambers for connecting to a cooling machine; the protective cover is provided with at least one inlet pipe communicating with the inert gas chambers for connecting to an inert gas cylinder.

[0010] The bottom of the protective cover has an outlet that connects to the inert gas cavity and is close to the laser molten pool. The outlet is aligned with the extension direction of the laser molten pool, which is used to form a protective atmosphere covering the laser molten pool with the delivered inert gas.

[0011] The preferred technical solution adopted by the present invention to solve the above-mentioned technical problems is as follows: the protective cover is disposed in the middle of the base, so that two laser molten pools are formed on both sides of the protective cover;

[0012] The protective cover contains a cooling chamber and two inert gas chambers arranged side by side and isolated from each other, with the cooling chamber positioned between the two inert gas chambers;

[0013] The bottom of the protective cover has an outlet on each side that connects to the inert gas chamber on the same side, and the two outlets are close to the laser melting pool on the same side.

[0014] The preferred technical solution adopted by the present invention to solve the above-mentioned technical problems is as follows: the shape of the protective cover matches the shape of the track working surface, including a longitudinal cover part that matches the top surface of the track and a vertical cover part that matches the side surface of the track, and the longitudinal cover part and the vertical cover part are smoothly transitioned by a transition rounded corner;

[0015] The cooling chamber and the inert gas chamber extend in the same direction as the protective cover;

[0016] Each of the inert gas chambers is connected to two air inlet pipes, one of which is located in the longitudinal cover and the other is located at the transition fillet and aligned with the portion of the inert gas chamber located inside the vertical cover.

[0017] One of the inlet pipe and the outlet pipe is located in the longitudinal cover, and the other is located at the transition rounded corner, aligned with the portion of the cooling cavity located inside the vertical cover.

[0018] The preferred technical solution adopted by the present invention to solve the above-mentioned technical problems is as follows: the base is further provided with at least one smoke collection pipe for connecting a vacuum cleaner, the smoke collection pipe having a smoke inlet facing the laser melting pool; the smoke inlet is rectangular, and its length extends in the same direction as the longitudinal extension direction of the laser melting pool.

[0019] The preferred technical solution adopted by the present invention to solve the above-mentioned technical problem is as follows: at least one pair of roller sets are provided on the base, the roller sets include a first roller that can roll along the top surface of the track and a second roller that can roll along the side surface of the track.

[0020] The preferred technical solution adopted by the present invention to solve the above-mentioned technical problems is as follows: the base is provided with at least one connecting arm, the connecting arm is used to connect with the track reinforcement vehicle so that the base moves synchronously along the track with the track reinforcement vehicle; the connecting arm is set on the base by an elastic device.

[0021] Another technical solution adopted by the present invention to solve the above-mentioned technical problems is: a laser molten pool gas protection device applied to a track-enhanced vehicle, including a base that can move along the track and a protective cover installed on the base, wherein the base allows a laser beam to pass through and form a laser molten pool on the track working surface;

[0022] The protective cover contains parallel, isolated cooling chambers and at least one inert gas chamber; the protective cover is provided with an inlet pipe and an outlet pipe communicating with the cooling chambers for connecting to a cooling machine; the protective cover is provided with at least one inlet pipe communicating with the inert gas chambers for connecting to an inert gas cylinder.

[0023] The bottom of the protective cover has an outlet that connects to the inert gas cavity and is close to the laser molten pool. The outlet is aligned with the extension direction of the laser molten pool and is used to form a protective atmosphere covering the laser molten pool from the inert gas.

[0024] The base is also provided with at least one smoke collection pipe for connecting a vacuum cleaner. The smoke collection pipe has a smoke inlet facing the laser melting pool. The smoke inlet is rectangular and its length extends in the same direction as the longitudinal extension direction of the laser melting pool.

[0025] Another preferred technical solution adopted by the present invention to solve the above-mentioned technical problems is: the protective cover is disposed in the middle of the base, so that two laser molten pools are formed on both sides of the protective cover;

[0026] The protective cover contains a cooling chamber and two inert gas chambers arranged side by side and isolated from each other, with the cooling chamber positioned between the two inert gas chambers;

[0027] The bottom of both sides of the protective cover are respectively provided with an outlet that connects to the inert gas cavity on the same side, and the two outlets are respectively close to the laser melting pool on the same side.

[0028] The base is provided with two smoke collection tubes at each end, which are used to place the two laser melting pools between the two smoke collection tubes, and the smoke inlets of the two smoke collection tubes are arranged opposite each other.

[0029] Another preferred technical solution adopted by the present invention to solve the above-mentioned technical problems is: the shape of the protective cover matches the shape of the track working surface, including a longitudinal cover part that matches the top surface of the track and a vertical cover part that matches the side surface of the track, and the longitudinal cover part and the vertical cover part are smoothly transitioned by a transition rounded corner;

[0030] The cooling chamber and the inert gas chamber extend in the same direction as the protective cover;

[0031] Each of the inert gas chambers is connected to two air inlet pipes, one of which is located in the longitudinal cover and the other is located at the transition fillet and aligned with the portion of the inert gas chamber located inside the vertical cover.

[0032] One of the water inlet pipe and the water outlet pipe is located in the longitudinal cover, and the other is located at the transition rounded corner, aligned with the part of the cooling cavity located inside the vertical cover.

[0033] The smoke inlet is rectangular, and its extension direction is consistent with that of the longitudinal hood.

[0034] Another preferred technical solution adopted by the present invention to solve the above-mentioned technical problems is: the base is provided with at least one pair of roller groups, the roller groups including a first roller that can roll along the top surface of the track and a second roller that can roll along the side surface of the track;

[0035] The base is provided with at least one connecting arm, which is used to connect with the track reinforcement vehicle so that the base moves synchronously along the track with the track reinforcement vehicle; the connecting arm is set on the base by an elastic device.

[0036] Another technical solution adopted by the present invention to solve the above-mentioned technical problems is: a laser molten pool gas protection method applied to a track-strengthened vehicle.

[0037] The coolant circulates within the cooling chamber through the inlet and outlet pipes of the protective cover to provide circulating cooling for the protective cover.

[0038] The laser beam is projected onto the track working surface through the base to form a laser molten pool within the track working surface;

[0039] Inert gas enters the inert gas chamber of the protective cover through the inlet pipe and is sent out from the outlet at the bottom of the protective cover, which is aligned with the extension direction of the laser molten pool, to form an inert gas protective atmosphere covering the laser molten pool.

[0040] The smoke inlet, whose length extends in the same direction as the longitudinal extension of the laser molten pool, draws the smoke generated by the laser molten pool into the smoke collection pipe.

[0041] The base, along with the protective cover and smoke collection pipe, moves synchronously along the track with the track-enhanced vehicle, ensuring that the laser molten pool is always kept within the protective atmosphere range.

[0042] Compared with the prior art, the advantages of the present invention are as follows: The laser molten pool gas protection device provided by the present invention leads the entire device to move synchronously with the laser device along the track through a base that can move along the track. By opening an outlet at the bottom of the protective cover that is consistent with the extension direction of the laser molten pool and continuously supplying inert gas, a highly sealed inert gas protective atmosphere with a matching shape and covering the entire length of the laser molten pool is formed, effectively preventing oxidation reaction in the laser molten pool. By setting a cooling chamber parallel to and isolated from the inert gas chamber in the protective cover, heat on the protective cover is continuously removed, keeping the temperature of the protective cover within a safe range. Furthermore, by setting a smoke inlet facing the laser molten pool and extending in the same direction as the longitudinal extension direction of the laser molten pool, smoke and exhaust gas generated during the laser alloying process are collected. Attached Figure Description

[0043] The present invention will be further described in detail below with reference to the accompanying drawings and preferred embodiments. However, those skilled in the art will understand that these drawings are drawn only for the purpose of explaining the preferred embodiments and therefore should not be construed as limiting the scope of the invention. Furthermore, unless specifically indicated, the drawings are only schematic representations of the composition or structure of the described objects and may contain exaggerated depictions, and the drawings are not necessarily drawn to scale.

[0044] Figure 1 A schematic diagram of a laser device used by a track-strengthening vehicle to perform surface strengthening operations on the track;

[0045] Figure 2 A schematic diagram of the laser device and the laser molten pool gas protection device for the track-enhanced vehicle;

[0046] Figure 3 This is a schematic diagram of the structure of a laser molten pool gas protection device according to a preferred embodiment of the present invention. Figure 1 ;

[0047] Figure 4 This is a schematic diagram of the structure of a laser molten pool gas protection device according to a preferred embodiment of the present invention. Figure 2 ;

[0048] Figure 5 This is a schematic diagram of the structure of a protective cover according to a preferred embodiment of the present invention. Figure 1 ;

[0049] Figure 6 This is a schematic diagram of the structure of a protective cover according to a preferred embodiment of the present invention. Figure 2 ;

[0050] Figure 7 This is a schematic diagram of the structure of a protective cover according to a preferred embodiment of the present invention. Figure 3 ;

[0051] Figure 8 for Figure 7 Cross-sectional view at point A;

[0052] Figure 9 This is a schematic diagram illustrating the working principle of a laser molten pool gas protection device according to a preferred embodiment of the present invention.

[0053] Figure 10 This is a schematic diagram of the structure of a laser molten pool gas protection device according to a preferred embodiment of the present invention. Figure 3 ;

[0054] Explanation of reference numerals in the attached figures:

[0055] Laser device 200, main body 201, laser head assembly 210, 220, laser head 202, laser beam 203, laser beam array 211, 221, laser molten pool r1, r2, track 300, top surface 301, inner surface 302, track working surface f, laser molten pool gas protection device 100, base 10, upper crossbeam 11, lower crossbeam 12, side beam 13, working area 14, protective cover 20, longitudinal cover 20z Vertical cover 20s, transition rounded corner 20y, cooling chamber 21, inert gas chamber 22a, 22b, water inlet pipe 23i, water outlet pipe 23o, air inlet pipe 24, air outlet 25a, 25b, isolation plate 26, smoke collection pipe 30a, 30b, smoke inlet 31a, 31b, suction end 32, collection end 33, roller group 40, first roller 41, second roller 42, connecting arm 50, elastic device 51. Detailed Implementation

[0056] Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings. Those skilled in the art will appreciate that these descriptions are merely descriptive and exemplary and should not be construed as limiting the scope of the invention.

[0057] In the description of this invention, it should be noted that the terms "upper," "lower," "front," "rear," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this invention is in use. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention. Similarly, terms such as "first" and "second" are only for the purpose of facilitating understanding and have no other directional meaning, and should not be regarded as limitations on this invention.

[0058] like Figure 1 The diagram illustrates the surface enhancement operation performed on track 300 by the laser device 200 of the track enhancement vehicle. During train operation, the wheels typically contact the top surface 301 and inner surface 302 of track 300. Therefore, the track surface f requiring surface enhancement includes at least a portion of the top surface 301 of track 300 (i.e., at least the portion near the inner surface 302), at least a portion of the inner surface 302 of track 300 (i.e., at least the portion near the top surface 301), and the transition area between the two. Thus, the track surface f extends laterally along the length of track 300, and its vertical cross-section is approximately inverted L-shaped.

[0059] In the following description, for ease of explanation and understanding, "horizontal" refers to the length direction of track 300, "vertical" refers to the width direction of track 300, and "height" refers to the height direction of track 300.

[0060] Therefore, as Figure 1 As shown, the laser device 200 includes a main body 201 and two rows of parallel laser head groups 210 and 220. Each row of laser head groups 210 and 220 consists of multiple laser heads 202 arranged in an arc. During operation, each laser head 202 emits a laser beam 203 towards the track working surface f, thereby generating two rows of parallel laser beams 211 and 221. After the two rows of laser beams 211 and 221 strike the track working surface f, two laser molten pools r1 and r2 are generated on the track working surface f, thereby alloying the special coating and track surface layer on the track working surface f, achieving track surface reinforcement.

[0061] As can be seen, the two laser molten pools r1 and r2 extend from the top surface 301 of the track 300 to the inner surface 302, roughly inverted L-shape. To avoid oxidation reactions between the heat generated during laser operation and oxygen, existing inert gas protection devices and methods are difficult to apply. In addition, in order to perform surface reinforcement work on the entire track 300 and ensure the consistency of strength at all points on the track working surface f, the track reinforcement vehicle leads the laser device 200 to travel at almost a constant speed along the track 300. Therefore, the two laser molten pools r1 and r2 move synchronously along the length of the track working surface f at almost a constant speed. The inert gas protective atmosphere must move synchronously with the laser molten pools r1 and r2. It is necessary to further overcome the problem that the gas drifts and deviates due to inertia, causing oxygen to seep into the laser molten pools r1 and r2.

[0062] like Figures 2 to 10 The laser molten pool gas protection device 100 provided in this embodiment can be applied in a track-enhanced vehicle and move synchronously with the aforementioned laser device 200 along the track 300. It includes a base 10 that can move along the track 300 and a protective cover 20 installed on the base 10.

[0063] like Figure 10 As shown, the base 10 includes an upper crossbeam 11 located on the top surface 301 of the track 300, a lower crossbeam 12 located on the inner side surface 302 of the track 300, and two side beams 13 connecting the two ends of the upper crossbeam 11 and the lower crossbeam 12. The side beams 13 extend from the top surface 301 of the track 300 to the inner side surface 302 of the track 300, and are approximately inverted L-shaped. Thus, the track working surface f of the track 300 can be exposed from the working area 14 enclosed by the upper crossbeam 11, the lower crossbeam 12 and the two side beams 13. Two rows of laser beams 211 and 221 strike the portion of the surface f to be reinforced within the working area 14, and two laser molten pools r1 and r2 are formed within the working area 14.

[0064] like Figure 3 , Figure 4 , Figure 9 and Figure 10As shown, the protective cover 20 is positioned between and beside the laser melting pools r1 and r2 to accommodate both sides of the laser melting pools r1 and r2. The overall shape of the protective cover 20 matches the working surface f of the track, and its vertical cross-section extends from the top surface 301 of the track 300 to the inner surface 302, roughly inverted L-shape. Its two ends are fixedly mounted on the upper crossbeam 11 and lower crossbeam 12 of the base 10, respectively, so that it can move along the track 300 together with the base 10.

[0065] like Figures 5 to 8 As shown, the protective cover 20 has a cooling chamber 21 and at least one inert gas chamber arranged side by side and isolated from each other. In this embodiment, in order to take into account the laser molten pools r1 and r2 on both sides, a cooling chamber 21 and two inert gas chambers 22a and 22b are arranged side by side and isolated from each other in the protective cover 20. The cooling chamber 21 is located between the two inert gas chambers 22a and 22b. The inert gas chambers 22a and 22b are respectively located near the laser molten pools r1 and r2. The cooling chamber 21 and the inert gas chambers 22a and 22b are separated from each other by an isolation plate 26. The isolation plate 26 is a sealing plate that is neither water-proof nor air-proof.

[0066] The protective cover 20 has an inlet pipe 23i and an outlet pipe 23o at the top position, which are connected to the cooling chamber 21 for connecting to the cooling machine of the track reinforcement vehicle. The protective cover 20 also has at least one air inlet pipe 24 at the top, which is connected to the inert gas chambers 22a and 22b for connecting to the inert gas cylinder of the track reinforcement vehicle.

[0067] The bottom of the protective cover 20 has an outlet that connects to the inert gas chambers 22a and 22b and is close to the laser molten pool. Since this embodiment has two inert gas chambers 22a and 22b, corresponding to two outlets 25a and 25b, the bottom sides of the protective cover 20 have outlets 25a and 25b that connect to the inert gas chambers 22a and 22b on the same side. The two outlets 25a and 25b are close to the laser molten pools r1 and r2 on the same side, respectively. The outlet 25a of the inert gas chamber 22a, which is close to the laser molten pool r1, is located on the bottom side of the protective cover 20 near the laser molten pool r1. Similarly, the outlet 25b of the inert gas chamber 22b, which is close to the laser molten pool r2, is located on the bottom side of the protective cover 20 near the laser molten pool r2.

[0068] After the inert gas enters the inert gas chambers 22a and 22b through the inlet pipe 24, it is sent out through the outlets 25a and 25b to the laser molten pools r1 and r2 respectively, so that the sent inert gas forms a protective atmosphere covering the laser molten pools r1 and r2. Therefore, in order to ensure that the protective atmosphere can cover the entire laser molten pools r1 and r2, the outlets 25a and 25b are aligned with the extension direction of the laser molten pools r1 and r2, and can cover the entire length of the laser molten pools r1 and r2.

[0069] Specifically, in this embodiment, firstly, the protective cover 20 extends from the top surface 301 of the track 300 to the inner side surface 302 of the track 300, so that the overall shape of the protective cover 20 matches the track working surface f, but maintains a certain distance from the track working surface f. Its vertical cross-section also extends from the top surface 301 of the track 300 to the inner side surface 302, roughly inverted L-shape. The cooling chamber 21 and the inert gas chambers 22a and 22b are laterally distributed inside the protective cover 20, and their extension direction is consistent with the protective cover 20, and they almost penetrate the entire length of the protective cover 20. At the same time, the air outlets 25a and 25b are opened as a narrow opening along the bottom of the protective cover 20, which also almost penetrates the entire length of the protective cover 20, extending from the top surface 301 of the track 300 to the inner side surface 302 of the track 300. Therefore, for the laser molten pools r1 and r2 extending from the top surface 301 of the track 300 to the inner surface 302 of the track 300 in this embodiment, the design of the protective cover 20 and its air outlets 25a and 25b can cover the entire length of the laser molten pools r1 and r2, and their shapes match.

[0070] Furthermore, such as Figure 3 , Figure 4 , Figure 9 and Figure 10 As shown, the base 10 is also equipped with at least one smoke collection pipe for connecting to the vacuum cleaner of the track-enhanced vehicle. Similarly, to accommodate the laser melting pools r1 and r2 on both sides, the base 10 in this embodiment is equipped with two smoke collection pipes 30a and 30b. The two smoke collection pipes 30a and 30b are respectively located beside the laser melting pools r1 and r2, and have smoke inlets 31a and 31b facing the laser melting pools r1 and r2. In this embodiment, the smoke inlets 31a and 31b of each smoke collection pipe 30a and 30b face the laser melting pools r1 and r2 on the same side, and are opposite to the air outlets 25a and 25b of the protective cover 20 on the same side. The smoke inlet 31a of the smoke collection pipe 30a closer to the laser melting pool r1 faces the direction of the laser melting pool r1, and the smoke inlet 31b of the smoke collection pipe 30b closer to the laser melting pool r2 faces the direction of the laser melting pool r2.

[0071] Specifically, smoke collection pipes 30a and 30b are fixedly installed on the upper crossbeam 11 of the base 10. Their suction end 32 passes through the upper crossbeam 11 and reaches above the working area 14, beside the laser melting pools r1 and r2. The collection end 33 bends upward from the back of the upper crossbeam 11 and connects to the vacuum cleaner of the track-enhanced vehicle. Smoke inlets 31a and 31b are opened along the length of the suction end 32 and are rectangular. The extension direction of their length is consistent with the longitudinal extension direction of the laser melting pools r1 and r2. Preferably, their extension direction is perpendicular to the forward direction of the track-enhanced vehicle.

[0072] The following description, in conjunction with the laser molten pool gas protection method for use in a track-strengthening vehicle provided by this invention, explains the working principle and advantages of the laser molten pool gas protection device 100 provided by this invention. The laser molten pool gas protection method for use in a track-strengthening vehicle is as follows:

[0073] The coolant circulates in the cooling chamber 21 through the inlet pipe 23i and outlet pipe 23o of the protective cover 20 to circulate and cool the protective cover 20.

[0074] It should be noted that the laser alloying process generates a large amount of heat. This heat can cause oxidation when the laser molten pool comes into contact with oxygen, and can also damage the protective cover 20. Therefore, the coolant flowing in the cooling chamber 21 can quickly remove the heat from the protective cover 20, keeping its temperature within a safe range.

[0075] In addition, to effectively ensure that the protective cover 20 is not damaged by the heat during operation, the coolant circulation in the cooling chamber 21 must be started first before turning on the laser device 200 of the track enhancement vehicle, and then the laser head assembly 210 and 220 of the laser device 200 are turned on.

[0076] Laser beams 211 and 221 project lasers through base 10 onto the track working surface f to form laser molten pools r1 and r2 on the track working surface f located within the working area 14;

[0077] At this time, the track reinforcement vehicle starts and leads the laser device 200 and the laser molten pool gas protection device 100 to move synchronously and at a constant speed along the length of the track 300. The laser beams 211 and 221 sweep evenly across the track working surface f, generating laser molten pools r1 and r2 where they are swept, alloying the special coating on the track working surface f with the track surface layer, thereby performing track surface reinforcement work.

[0078] Inert gas enters the inert gas chambers 22a and 22b of the protective cover 20 through the inlet pipe 24, and is discharged from the outlets 25a and 25b at the bottom of the protective cover 20, which are aligned with the extension direction of the laser molten pools r1 and r2, so as to form an inert gas protective atmosphere covering the laser molten pools r1 and r2.

[0079] It should be noted that, firstly, since the extension direction and shape of the vents 25a and 25b are consistent with those of the laser molten pools r1 and r2, the inert gas protective atmosphere they generate can cover the entire length of the laser molten pools r1 and r2. Secondly, the vents 25a and 25b are respectively located at the bottom of the protective cover 20 near the laser molten pools r1 and r2 on the same side, rather than directly on the side facing the laser molten pools r1 and r2. When the inert gas is sent out from the vents 25a and 25b, it can first be blown downwards onto the track working surface f, and then closely adhere to the surface of the track working surface f to reach the laser molten pools r1 and r2, displacing the air around the laser molten pools r1 and r2. It can also prevent oxygen from seeping into the laser molten pools r1 and r2 from the bottom of the protective atmosphere. Therefore, the protective cover 20 can generate an inert gas protective atmosphere that matches the shape and length of the laser molten pools r1 and r2 and has a high degree of sealing, effectively preventing oxidation reactions from occurring in the laser molten pools r1 and r2.

[0080] In addition, argon or nitrogen can be used as the inert gas. Argon or nitrogen cylinders are installed on the track reinforcement vehicle. The inlet pipes 24 of the inert gas chambers 22a and 22b are connected to the inert gas cylinders, continuously supplying inert gas into the inert gas chambers 22a and 22b.

[0081] The smoke inlets 31a and 31b, whose length extension direction is consistent with the longitudinal extension direction of the laser molten pools r1 and r2, draw the smoke generated by the laser molten pools r1 and r2 into the smoke collection pipes 30a and 30b.

[0082] It should be noted that the fumes and exhaust gases generated during the laser and coating alloying process are not necessarily recycled in some embodiments. However, for the sake of environmental protection, the fumes and exhaust gases are collected by the fumes collection pipes 30a and 30b.

[0083] In addition, the smoke inlets 31a and 31b are rectangular, and their length extends in the same direction as the longitudinal extension of the laser molten pools r1 and r2, so that the smoke and exhaust gas can be drawn in more fully in the longitudinal direction. Preferably, their extension direction is perpendicular to the forward direction of the track-enhanced vehicle. When the laser molten pool gas protection device 100 moves synchronously along the track, the smoke and exhaust gas can enter the smoke inlets 31a and 31b, further improving the collection efficiency of the smoke and exhaust gas.

[0084] Furthermore, the smoke inlets 31a and 31b are positioned opposite to the exhaust outlets 25a and 25b of the protective cover 20 on the same side. The inert gas continuously delivered from the exhaust outlets 25a and 25b can also push the smoke and exhaust gas into the smoke inlets 31a and 31b.

[0085] The base 10 leads the protective cover 20 and the smoke collection tubes 30a and 30b to move synchronously along the track 300 with the track-enhancing vehicle, so that the laser molten pools r1 and r2 are always kept within the working area 14, on both sides of the protective cover 20, between the two smoke collection tubes 30a and 30b, and within the protective atmosphere.

[0086] Therefore, the laser molten pool gas protection device 100 provided by the present invention leads the entire device along the laser device 200 to move along the track 300 via the base 10 that can move along the track 300. By opening the gas outlets 25a and 25b at the bottom of the protective cover 20 close to and consistent with the extension direction of the laser molten pools r1 and r2, and continuously supplying inert gas, a highly sealed inert gas protective atmosphere with matching shape and covering the entire length of the laser molten pools r1 and r2 is formed, effectively preventing oxidation reaction in the laser molten pools r1 and r2. By setting the cooling chamber 21 in the protective cover 20 parallel to and isolated from the inert gas chambers 22a and 22b, the heat on the protective cover 20 is continuously removed, and the temperature of the protective cover 20 is controlled within a safe range. Furthermore, by setting the smoke inlet 31a and 31b facing the laser molten pools r1 and r2 and with the extension direction consistent with the longitudinal extension direction of the laser molten pools r1 and r2, the smoke and exhaust gas generated during the laser alloying process are collected.

[0087] It should be noted that in other embodiments, if the laser device 200 is provided with one or more rows of laser head groups, and one or more laser molten pools are formed on the track working surface f accordingly, the protective cover 20 and the smoke collection pipe should also be adjusted accordingly. For example, a corresponding number of inert gas chambers are provided in the protective cover 20, and a corresponding number of smoke collection pipes are provided on the base 10. Each inert gas chamber, outlet and smoke inlet of the smoke collection pipe is responsible for the protection of one laser molten pool.

[0088] In another embodiment, the protective cover 20 is disposed on one side of the base 10, the smoke collection pipe 30 is disposed on the other side of the base 10, an inert gas chamber is disposed on the side of the protective cover 20 facing the smoke collection pipe, and the outlet is located at the bottom of the protective cover 20, connecting to the inert gas chamber and close to the smoke collection pipe, while the smoke inlet faces the protective cover 20. Regardless of the number of laser molten pools, they are all formed on the track working surface f between the outlet of the protective cover 20 and the smoke inlet of the smoke collection pipe. The inert gas delivered from the outlet forms a protective atmosphere that covers and seals all the laser molten pools.

[0089] However, this implementation method is more suitable for situations with only one laser molten pool. For two or more laser molten pools, the protective atmosphere formed by the inert gas sent out from the outlet of an inert gas chamber needs to travel a long path to cover all laser molten pools, and its stability and sealing are not as good as this embodiment.

[0090] like Figures 5 to 8 As shown, the shape of the protective cover 20 matches the shape of the track working surface f, specifically including a longitudinal cover portion 20z that matches the top surface 301 of the track 300 and a vertical cover portion 20s that matches the inner surface 302 of the track 300. The longitudinal cover portion 20z and the vertical cover portion 20s are smoothly transitioned by a transition fillet 20y. The cooling cavity 21 and the inert gas cavities 22a and 22b inside the protective cover 20 are arranged in parallel and laterally spaced along the same extension direction as the protective cover 20.

[0091] The advantages of this design are twofold: firstly, after the inert gas enters the inert gas chambers 22a and 22b, it forms a gas shape consistent with the extension direction of the laser molten pools r1 and r2. Thus, when the inert gas is discharged from the outlets 25a and 25b, which are consistent with the extension direction of the laser molten pools r1 and r2, a relatively uniform and isotropic inert gas protective atmosphere can be generated; secondly, the coolant can fully contact the protective cover 20 through the cooling chamber 21, thereby improving the cooling efficiency.

[0092] Each inert gas cavity 22a, 22b is connected to two inlet pipes 24. One inlet pipe 24 is located in the longitudinal cover 20z, and the other inlet pipe is located at the transition fillet 20y, aligned with the portion of inert gas cavities 22a, 22b located within the vertical cover 20s. This results in a more uniform distribution of inert gas within the entire inert gas cavity 22a, 22b, and a more uniform distribution of gas along the extension directions of the laser molten pool r1, r2 when it exits from the outlets 25a, 25b, with a more sufficient gas pressure.

[0093] The inlet pipe 23i is located in the longitudinal cover portion 20z, and the outlet pipe 23o is located at the transition fillet 20y, aligned with the portion of the cooling chamber 21 located within the vertical cover portion 20s. This ensures that the coolant can circulate fully within the entire cooling chamber 21, providing sufficient cooling for the entire extension direction of the protective cover 20. Of course, the positions of the inlet pipe 23i and the outlet pipe 23o can be interchanged, but the arrangement used in this embodiment allows the coolant to flow smoothly from the longitudinal cover portion 20z into the vertical cover portion 20s using its own weight, thereby reducing power consumption.

[0094] like Figure 3 and Figure 4As shown, the base 10 is provided with at least one pair of roller sets 40. Each roller set 40 includes a first roller 41 that can roll along the top surface 301 of the track 300 and a second roller 42 that can roll along the inner side surface 302 of the track 300, allowing the base 10 to move smoothly and stably on the track 300. In this embodiment, there are two pairs of roller sets 40, respectively installed on the outer sides of the two side beams 13 of the base 10. The two first rollers 41 are vertically arranged to roll along the top surface 301 of the track 300, and the two second rollers 42 are horizontally arranged to roll along the inner side surface 302 of the track 300. Providing two pairs of roller sets 40, along with the first rollers 41 and the second rollers 42, makes the entire device move more smoothly and steadily.

[0095] like Figures 2 to 4 As shown, the base 10 is provided with at least one connecting arm 50, which is used to connect with the track reinforcement vehicle so that the base 10 moves synchronously along the track with the track reinforcement vehicle. In this embodiment, a total of two connecting arms 50 are provided. The lower ends of the two connecting arms 50 are respectively connected to the upper ends of the two side beams 13 of the base 10, and the upper ends are respectively connected to both sides of the main body 201 of the laser device 200. The connecting arms 50 are set on the base 10 by elastic devices 51. In this embodiment, the elastic device 51 is a spring. The lower end of the connecting arm 50 is connected to the upper end of the side beam 13 through the spring, so that when the base 10 moves along the track 300, and turns and undulates synchronously with the turning and undulation of the track 300, the elastic device 51 can play a buffering role.

[0096] It should be noted that similar labels in the following figures indicate similar items; therefore, once an item is defined in one figure, it may not be further defined and explained in subsequent figures.

[0097] The above describes the laser molten pool gas protection device and protection method for track-enhanced vehicles provided by this invention. Specific examples have been used to illustrate the principles and implementation methods of this invention. The descriptions of the embodiments above are only for the purpose of helping to understand this invention and its core ideas. It should be noted that those skilled in the art can make several improvements and modifications to this invention without departing from the principles of this invention, and these improvements and modifications also fall within the protection scope of the claims of this invention.

Claims

1. A laser molten pool gas protection device applied to a track-strengthened vehicle, characterized in that: It includes a base that can move along a track and a protective cover mounted on the base, the base allowing a laser beam to pass through and form a laser molten pool on the track working surface; The protective cover contains a cooling chamber and two inert gas chambers arranged side by side and isolated from each other, with the cooling chamber located between the two inert gas chambers; the protective cover is provided with an inlet pipe and an outlet pipe communicating with the cooling chamber for connecting to a cooling machine; the protective cover is provided with at least one inlet pipe communicating with the inert gas chamber for connecting to an inert gas cylinder. The bottom of the protective cover has an outlet that connects to the inert gas cavity and is close to the laser molten pool. The outlet is aligned with the extension direction of the laser molten pool and is used to form a protective atmosphere covering the laser molten pool from the inert gas. The base includes an upper crossbeam located on the top surface of the track, a lower crossbeam located on the inner side of the track, and two side beams connecting the two ends of the upper crossbeam and the lower crossbeam. The side beams extend from the top surface of the track to the inner side of the track, so that the track working surface is exposed from the working area enclosed by the upper crossbeam, the lower crossbeam and the two side beams. Two laser melting pools are formed in the working area. The protective cover is located in the middle of the base, so that two laser molten pools are formed on both sides of the protective cover; the two ends of the protective cover are respectively fixedly installed on the upper crossbeam and the lower crossbeam of the base; The bottom of both sides of the protective cover are respectively provided with an outlet that connects to the inert gas cavity on the same side, and the two outlets are respectively close to the laser melting pool on the same side. The shape of the protective cover matches the shape of the track working surface, including a longitudinal cover portion that matches the top surface of the track and a vertical cover portion that matches the side surface of the track, with a smooth transition between the longitudinal cover portion and the vertical cover portion using a transition rounded corner. The cooling chamber and the inert gas chamber extend in the same direction as the protective cover; Each of the inert gas chambers is connected to two air inlet pipes, one of which is located in the longitudinal cover and the other is located at the transition fillet and aligned with the portion of the inert gas chamber located inside the vertical cover. One of the water inlet pipe and the water outlet pipe is located in the longitudinal cover, and the other is located at the transition rounded corner, aligned with the part of the cooling cavity located inside the vertical cover. The base has two smoke collection pipes at each end for connecting to a vacuum cleaner, so that the two laser melting pools are located between the two smoke collection pipes; the smoke collection pipes have smoke inlets facing the laser melting pools, and the smoke inlets of the two smoke collection pipes are arranged opposite each other; The smoke collection pipe is fixedly installed on the upper crossbeam of the base. Its suction end passes through the upper crossbeam to the top of the working area and the side of the laser melting pool. The collection end bends upward from the back of the upper crossbeam and is used to connect to the vacuum cleaner of the rail reinforcement vehicle. The smoke inlet is opened along the length of the suction end and is rectangular. Its length extension direction is consistent with the longitudinal extension direction of the laser melting pool and is used to be perpendicular to the forward direction of the rail reinforcement vehicle. The base is provided with at least one connecting arm, which is used to connect with the track reinforcement vehicle so that the base moves synchronously along the track with the track reinforcement vehicle; the connecting arm is set on the base by an elastic device.

2. The laser molten pool gas protection device for track-enhanced vehicles according to claim 1, characterized in that: The base is provided with at least one pair of roller sets, the roller sets including a first roller that can roll along the top surface of the track and a second roller that can roll along the side surface of the track.

3. A laser molten pool gas protection method applied to a track-strengthened vehicle, characterized in that: Performed by the laser molten pool gas protection device for track-enhanced vehicles as described in any one of claims 1-2; Before turning on the laser device of the orbital augmentation vehicle, the coolant circulation in the cooling chamber is started first; The coolant circulates within the cooling chamber through the inlet and outlet pipes of the protective cover to provide circulating cooling for the protective cover. The laser beam is projected onto the track working surface through the base to form a laser molten pool within the track working surface; Inert gas enters the inert gas chamber of the protective cover through the inlet pipe and is sent out from the outlet at the bottom of the protective cover, which is aligned with the extension direction of the laser molten pool, to form an inert gas protective atmosphere covering the laser molten pool. The smoke inlet, whose length extends in the same direction as the longitudinal extension of the laser molten pool, draws the smoke generated by the laser molten pool into the smoke collection pipe. The base leads the protective cover and smoke collection tube to move synchronously along the track with the track-enhanced vehicle, so that the laser molten pool is always kept within the protective atmosphere range, and the inert gas sent out from the gas outlet pushes the smoke into the smoke collection tube.

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