Laser impact device for precise spraying of uniform water confinement layer in fixture

Abstract

The present invention relates to a laser impact device for precisely spraying a uniform water confinement layer within a fixture. The fixture is mounted on an industrial robot, with a water pump's water inlet connected to a distilled water tank and its outlet connected to the inlet of an electromagnetic multi-way control valve. The fixture comprises a base and a carrier, the carrier being provided with a receiving slot for positioning a workpiece. A cover is mounted on the front and rear vertical plates of the carrier adjacent to the receiving slot. A cylindrical cavity is rotatably supported on the front and rear covers. Multiple partitions are radially disposed within the cylindrical cavity, dividing the inner cavity into multiple water inlets. The cylindrical cavity is connected to a water inlet connector connected to corresponding water inlets. A water curtain nozzle assembly is provided within the cylindrical cavity, with multiple water spray outlets distributed thereon. Each water spray outlet is connected to a corresponding water inlet, forming a water spray path through a water inlet and a water inlet connector. The multiple water inlet connectors are all connected to the outlet of the electromagnetic multi-way control valve. A motor is drivably connected to the cylindrical cavity. The water beam moves with the light spot, adjusting the thickness and angle of the sprayed water confinement layer.

Description

Technical Field

[0001] The invention relates to a laser shock device for precisely spraying a uniform water confinement layer in a fixture, belonging to the technical field of laser shock wave surface strengthening. Background Art

[0002] Since the birth of lasers, they have been widely used worldwide in just a few decades. As a research hotspot that is expected to replace traditional mechanical shot peening, the principle of laser shock peening is to transmit a high-energy laser beam through a confining layer to the absorption layer on the surface of the workpiece, causing a plasma to form in the absorption layer near the confining layer. Under the confinement of the confining layer, a high-intensity shock wave pressure is generated on the surface of the workpiece to be processed, with a peak pressure of GPa. This forms a fine grain structure on the surface of the workpiece and residual compressive stress on the surface, achieving the effect of fine grain strengthening and reducing fatigue cracks. Currently, the energy absorption layers commonly used in experiments are mainly black tape and aluminum foil, while the constraining layers are often deionized distilled water and glass.

[0003] The study found that the impact effect of the rigid constraint layer is significantly better than that of the flexible constraint. However, under the action of the laser, a certain residual stress is formed inside the rigid constraint layer. When the residual stress is greater than the tensile strength of the rigid constraint layer, the glass will break and need to be replaced regularly and in a timely manner, which affects the efficiency of the experiment and increases the cost. In addition, if the surface of the workpiece to be processed is uneven, the rigid constraint layer and the workpiece are not tightly fitted, which will also affect the effect of the impact. Therefore, flexible distilled water is often used as the constraint layer. The experiment found that: 1) The water nozzle of the original water constraint layer device is perpendicular to the workpiece surface and sprays water in the same direction as the laser irradiation. The position of the nozzle is not optimized during the impact process, resulting in uneven thickness of the water constraint layer, interference with the laser beam, and no water constraint layer on the surface of the workpiece to be processed at certain times, causing ablation of the absorption layer or poor impact effect; 2) Laser shock strengthening is carried out one by one at a time, while the water constraint layer covers a large area of ​​the processing area, resulting in unnecessary waste of water resources and increased processing costs. Summary of the Invention

[0004] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a laser impact device for accurately spraying a uniform water confinement layer in a fixture.

[0005] The purpose of the present invention is achieved through the following technical solutions:

[0006] A laser impact device for precisely spraying a uniform water confinement layer within a fixture is characterized by: an industrial robot positioned on one side of the laser, a fixture mounted on the industrial robot capable of driving a workpiece on the fixture toward the laser's optical path; a distilled water collection tank located beneath the fixture, connected to the distilled water tank via a distillation filter; a water pump inlet connected to the distilled water tank, and a water outlet connected to the inlet of an electromagnetic multi-way control valve;

[0007] The fixture includes a base connected to the flange seat and a carrier fixed to the base, the carrier is provided with a receiving groove for positioning the workpiece, the front and rear vertical plates of the carrier next to the receiving groove are installed with a cover body, the columnar cavity is rotatably supported on the front and rear cover bodies, a plurality of partitions are radially provided in the columnar cavity to divide the inner cavity into a plurality of water inlets, the columnar cavity is connected with a water inlet joint connected to the corresponding water inlet, a water curtain nozzle assembly is provided on the columnar cavity, a plurality of water spray outlets are distributed on the water curtain nozzle assembly, the water spray outlets are respectively connected to the corresponding water inlets, a water spray outlet forms a water spray passage through a water inlet and a water inlet joint, and the plurality of water inlet joints are all connected to the outlet of the electromagnetic multi-way control valve; the motor is connected to the columnar cavity drive and can drive it to rotate.

[0008] Furthermore, in the above-mentioned laser impact device for precisely spraying a uniform water confinement layer in a fixture, nine 25×15 mm rectangular water spray ports are evenly spaced on the curtain-shaped nozzle assembly.

[0009] Furthermore, in the above-mentioned laser impact device for precisely spraying a uniform water confinement layer in the fixture, a clamping plate is arranged on the outside of the workpiece, a locking bolt passes through the clamping plate and is screwed onto the carrier, and the locking bolt is adjusted to press the clamping plate toward the workpiece so that the workpiece is locked in the receiving groove.

[0010] Furthermore, in the above-mentioned laser impact device for precisely spraying a uniform water confinement layer in a fixture, the water curtain nozzle assembly is welded to the columnar cavity as one body, and the axial direction of the columnar cavity is parallel to the workpiece.

[0011] Furthermore, in the above-mentioned laser impact device for precisely spraying a uniform water confinement layer in a fixture, a control system is connected to the laser, the industrial robot, the water pump, the electromagnetic multi-way control valve and the motor control.

[0012] Furthermore, in the above-mentioned laser impact device for precisely spraying a uniform water confinement layer in a fixture, the motor is fixed to the flange seat via a fastening ring.

[0013] Furthermore, in the above-mentioned laser impact device for precisely spraying a uniform water confinement layer in a fixture, the main shaft of the motor is drivingly connected to the cylindrical cavity through a shaft coupling.

[0014] Compared with the prior art, the present invention has significant advantages and beneficial effects, which are specifically reflected in the following aspects:

[0015] ① The present invention is a device that integrates workpiece clamping and precise spraying of a stable and uniform water constraint layer. The water beam moves precisely with the light spot, and the thickness and angle of the sprayed water constraint layer can be adjusted, thereby improving the formation of the water constraint layer during laser shock treatment, achieving precise spraying, and saving water. By improving the angle of the constraint layer, the laser shock effect is improved, effectively achieving water-saving processing. After the shock treatment, the surface grain of the workpiece is refined, the residual stress is evenly distributed, and there is no stress void phenomenon.

[0016] ② The water confinement layer system is integrated into the fixture to fully utilize the fixture space and reduce the complexity of the laser shock system. During the laser shock process, it avoids problems such as uneven thickness of the water confinement layer, interference with the laser beam, and the absence of the water confinement layer on the surface of the workpiece at certain times, which may cause ablation of the absorption layer or poor shock effect, thereby improving the surface strengthening effect.

[0017] ③ As the light spot moves relative to the workpiece, the water constraint layer is precisely sprayed to maximize water conservation and reduce costs;

[0018] ④ The angle between the water constraint layer and the workpiece and the thickness of the constraint layer can be adjusted. The motor drives the cylindrical cavity and the water curtain nozzle assembly to rotate, so that the angle between the constraint layer and the workpiece ranges from 35° to 60°. By adjusting the flow rate, pressure and other parameters of the water pump, different thicknesses of water constraint layers can be indirectly formed under different conditions of the torrent impact force on the workpiece, ensuring the uniformity and stability of the impact strengthening quality.

[0019] ⑤ The clamping and positioning of the fixture is reliable and the repeated positioning accuracy is high. During the positioning and clamping process, the locking bolt passes through the clamping plate and is screwed onto the carrier. The locking bolt is adjusted to press the clamping plate toward the workpiece, so that the workpiece is locked in the receiving slot. Compared with the four screws on both sides of the clamping plate, the workpiece clamping time is greatly shortened, the efficiency is more than doubled, and the quality and production efficiency of the laser shock peening of the plate are improved;

[0020] ⑥ The water constraint layer acts on the surface of the workpiece to prevent the fixture from contacting water to the greatest extent, thus preventing the fixture from rusting due to being immersed in water.

[0021] Other features and advantages of the present invention will be described in the following description, and in part will become apparent from the description, or will be understood by practicing the specific embodiments of the present invention. The purposes and other advantages of the present invention can be realized and obtained by the structures particularly pointed out in the written description and the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying any creative work.

[0023] Figure 1 : A schematic structural diagram of the device of the present invention;

[0024] Figure 2 : Axonometric diagram of the fixture;

[0025] Figure 3 : Schematic diagram of the main view of the fixture;

[0026] Figure 4 : Side view of the fixture;

[0027] Figure 5 : Axonometric diagram of the cylindrical cavity;

[0028] Figure 6 : Schematic diagram of the main view of the cylindrical cavity;

[0029] Figure 7 : Figure 6 BB cross-sectional diagram. DETAILED DESCRIPTION

[0030] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, not all of the embodiments. The components of the embodiments of the present invention generally described and shown in the drawings herein can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed invention, 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.

[0031] It should be noted that similar reference numerals and letters represent similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined or explained in subsequent drawings. At the same time, in the description of the present invention, directional terms and order terms are only used to distinguish the description and should not be understood as indicating or implying relative importance.

[0032] like Figures 1 to 4As shown, a laser impact device for precisely spraying a uniform water confinement layer in a fixture is provided. An industrial robot 19 is arranged on one side of a laser 22. A fixture is mounted on the industrial robot 19, which can drive a workpiece on the fixture toward the optical path of the laser 22. A distilled water collection tank 23 is provided below the fixture. The distilled water collection tank 23 is connected to the distilled water tank 17 via a distillation filter 24. The water inlet of a water pump 18 is connected to the distilled water tank 17, and the water outlet is connected to the inlet of an electromagnetic multi-way control valve 20.

[0033] The fixture includes a base 1 connected to a flange seat 15 and a carrier 11 fixed to the base 1, and the base 1 is fixed to the flange seat 15 by four screws 2, and the flange seat 15 is connected to the industrial robot 19; a receiving groove for positioning the workpiece 6 is provided on the carrier 11, and a clamping plate 4 is arranged on the outside of the workpiece 6, and a locking bolt 3 passes through the clamping plate 4 and is screwed onto the carrier 11, and the locking bolt 3 is adjusted to press the clamping plate 4 toward the workpiece 6 so that the workpiece 6 is locked in the receiving groove; a cover body 12 is installed on the front and rear vertical plates of the carrier next to the receiving groove, and the cover body 12 has a central circular hole, and the rotating axis of the cylindrical cavity 8 is rotatably supported in the circular hole, and the cylindrical cavity 8 is rotatably supported on the front and rear covers, and a plurality of partitions are radially provided in the cylindrical cavity 8 to divide the inner cavity into a plurality of water inlets, such as Figures 5-7 , the cylindrical cavity 8 is connected to a water inlet joint 9 connected to the corresponding water inlet, and a water curtain nozzle assembly 7 is provided on the cylindrical cavity 8. The water curtain nozzle assembly 7 is welded to the cylindrical cavity 8 as a whole. The axial direction of the cylindrical cavity 8 is parallel to the workpiece 6. Nine 25×15mm rectangular water spray ports are evenly spaced on the water curtain nozzle assembly 7. The water spray ports are respectively connected to the corresponding water inlets. A water spray port forms a water spray passage through a water inlet and a water inlet joint. Multiple water inlet joints 9 are connected to the outlet of the electromagnetic multi-way control valve 20 through a water pipe 10; the motor 14 is fixed to the flange seat 15 by a fastening ring 16. The fastening ring 16 is shaped like a hoop structure and is locked by a nut 5. The main shaft of the motor 14 is driven and connected to the cylindrical cavity 8 through a shaft coupling 13, which can drive it to rotate.

[0034] To prevent rust, the clamping piece 4, flange 15, carrier 11, base 1, cylindrical cavity 8, and water curtain nozzle assembly 7 are all made of 316L stainless steel, the water pipe 10 is a high molecular polymer PB hose, the workpiece material is 40CrMo steel and Ti6AL4V alloy, and the screws and nuts are made of 304 stainless steel.

[0035] The control system 21 is connected to the laser 22, the industrial robot 19, the water pump 18, the electromagnetic multi-way control valve 20 and the motor 14 to form an integrated control.

[0036] The motor 14 drives the columnar cavity 8 and the water curtain nozzle assembly 7 to rotate at a small angle. Under the drive of the motor, the columnar cavity 8 and the water curtain nozzle assembly 7 adjust the optimal spray angle; the angle between the water curtain nozzle assembly and the workpiece 6 is adjusted to be small, the impact force acting on the workpiece is small, and the thickness of the water layer formed is slightly smaller than the width of the water outlet; the angle is large, the impact force is large, and a torrent is formed on the surface of the workpiece, so the thickness formed on the workpiece is small. The angle can be adjusted between 35° and 60°, and a uniform water layer with a certain flow rate is formed in contact with the surface of the workpiece.

[0037] There are 9 rectangular water spray outlets distributed on the water curtain nozzle assembly 7. In order to avoid the blind area of ​​the rectangular nozzle gap, the rectangular spray hole is a boss with an inclination angle of 3 to 5 degrees. Within the adjustable angle range, a uniform water constraint layer with a thickness of 5 to 12 mm can be stably formed.

[0038] The industrial robot 19 operates according to the established programming, and feeds back the position of the moving coordinates to the control system 21, and then controls the corresponding rectangular water outlets in the water curtain nozzle assembly 7 through the electromagnetic multi-way control valve 20 to spray the constraint layer; the laser spot irradiation point is relatively stationary, and the industrial robot 19 clamps the fixture to move. When the light spot corresponds to the first rectangular water outlet of the water curtain nozzle assembly 7, the moving position information of the industrial robot 19 is fed back to the control system 21, and the control system 21 controls the corresponding pipeline of the electromagnetic multi-way control valve 20 to open the water supply; when the light spot is close to the second rectangular water outlet of the water curtain nozzle assembly 7, the control system 21 controls the electromagnetic multi-way control valve 20 to close the previous water outlet and open the next water outlet, and so on, so as to always ensure that the water beam can be sprayed to the position of the light spot, thereby achieving the effect of water saving and precise spraying of the water constraint layer.

[0039] Adjust the angle of the water curtain nozzle assembly 7 and the flow rate and pressure of the water pump 18 to achieve the desired spray effect. After the first rectangular water jet forms a stable water confinement layer, activate the laser 22, adjust the laser impact parameters, and begin laser impact according to the pre-programmed trajectory. As the robot 19 moves, the control system 21 controls the electromagnetic multi-way control valve 20, controlling the opening and closing of the corresponding rectangular water jets in the water curtain nozzle assembly 7, thereby ensuring a uniform water confinement layer at the impact spot location. The processed distilled water is collected in the distilled water collection tank 23, filtered through the distillation filter 24, and then flows into the distilled water tank 17 for recycling.

[0040] Example:

[0041] Laser shock strengthened Ti6AL4V alloy material with improved constrained layer;

[0042] Pretreatment: A 10mm×8mm×5mm Ti6AL4V alloy workpiece was polished and cleaned with pyruvic acid. After drying in a drying oven, the side to be impact-strengthened was affixed with black high-temperature-resistant polyester tape and then placed in a fixture.

[0043] Adjust the water pump parameters: The control system starts the water constraint layer injection system and adjusts the water pump flow rate to 50L / min and the pressure to 15MPa;

[0044] Adjust the angle of the water curtain nozzle assembly: the motor rotates, driving the cylindrical cavity and the water curtain nozzle assembly to rotate, and select the appropriate spray angle;

[0045] Laser settings: Adjust the laser power parameters, laser wavelength 1024nm, laser energy 8J, pulse frequency 1.5Hz, square spot horizontal and vertical overlap rate 40%, impact number 1, and start the laser operation;

[0046] Industrial robot operation: When the laser is turned on, the industrial robot runs according to the established planned route program; according to the operating position of the industrial robot, the control system controls the opening and closing of the corresponding outlets of the electromagnetic multi-way control valve. During the whole process, the spray is accurately sprayed to the impact spot area, and the scanning area is set to a 50×50mm square area;

[0047] After the impact is completed, turn off the laser, jet, and industrial robot, remove the workpiece, and the operation is completed.

[0048] To sum up, the present invention is a device that integrates workpiece clamping and precise spraying of a stable and uniform water constraint layer. The water beam moves precisely with the light spot, and the thickness and angle of the sprayed water constraint layer can be adjusted, thereby improving the forming of the laser shock strengthened water constraint layer, achieving precise spraying, and saving water resources. By improving the angle of the constraint layer, the laser shock effect is improved, and water-saving processing is effectively realized. After impact treatment, the surface grains of the workpiece are refined, the residual stress is evenly distributed, and there is no stress void phenomenon, thereby reducing costs.

[0049] The water confinement layer system is integrated into the fixture to fully utilize the fixture space and reduce the complexity of the laser shock system. During the laser shock process, problems such as uneven thickness of the water confinement layer, interference with the laser beam, and the absence of the water confinement layer on the surface of the workpiece to be processed at certain moments, which may cause ablation of the absorption layer or poor shock effect, are avoided, thereby improving the surface strengthening effect.

[0050] As the light spot moves relative to the workpiece, the water constraint layer is precisely sprayed to maximize water conservation and reduce costs.

[0051] The clamping and positioning is reliable, and the repeated positioning accuracy is high. During the positioning and clamping process, the locking bolt passes through the clamping plate and is screwed onto the carrier. The locking bolt is adjusted to press the clamping plate toward the workpiece, so that the workpiece is locked in the receiving slot. Compared with clamping with four screws on both sides of the clamping plate, the workpiece clamping time is greatly shortened, the efficiency is more than doubled, and the quality and production efficiency of laser shock peening of plates are improved.

[0052] The angle between the water constraint layer and the workpiece and the thickness of the constraint layer can be adjusted. The motor drives the cylindrical cavity and the water curtain nozzle assembly to rotate, so that the angle between the constraint layer and the workpiece ranges from 35° to 60°. By adjusting the flow rate, pressure and other parameters of the water pump, water constraint layers of different thicknesses are indirectly formed under different conditions of the torrent impact force on the workpiece, ensuring the uniformity and stability of the impact strengthening quality.

[0053] The water constraint layer acts on the surface of the workpiece to prevent the fixture from contacting with water to the greatest extent, thus avoiding rusting of the fixture due to immersion in water.

[0054] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Various modifications and variations are readily apparent to those skilled in the art. Any modifications, equivalent substitutions, improvements, and the like made within the spirit and principles of the present invention are intended to be included within the scope of protection of the present invention. It should be noted that similar reference numerals and letters denote similar items in the following figures. Therefore, once an item is defined in one figure, it need not be further defined or explained in subsequent figures.

[0055] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with this technical field can easily think of changes or replacements within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

[0056] It should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply the existence of any such actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article, or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or device. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of other identical elements in the process, method, article, or device comprising the element.

Claims

1. Laser impact device for precisely spraying a uniform water confinement layer in a fixture, characterized by: An industrial robot (19) is arranged on one side of the laser (22). A fixture is installed on the industrial robot (19) to drive a workpiece on the fixture toward the optical path of the laser (22). A distilled water collection tank (23) is provided below the fixture. The distilled water collection tank (23) is connected to the distilled water tank (17) through a distillation filter (24). The water inlet of the water pump (18) is connected to the distilled water tank (17), and the water outlet is connected to the inlet of the electromagnetic multi-way control valve (20). The fixture comprises a base (1) connected to a flange seat (15) and a carrier (11) fixed to the base (1); a receiving groove for positioning a workpiece (6) is provided on the carrier (11); a cover (12) is installed on the front and rear vertical plates of the carrier next to the receiving groove; the columnar cavity (8) is rotatably supported on the front and rear covers; a plurality of partitions are radially provided in the columnar cavity (8) to divide the inner cavity into a plurality of water inlets; a water inlet joint (9) connected to the corresponding water inlets is connected to the columnar cavity (8); a water curtain nozzle assembly (7) is provided on the columnar cavity (8); a plurality of water spray ports are distributed on the water curtain nozzle assembly (7); the water spray ports are respectively connected to the corresponding water inlets; a water spray port forms a water spray passage through a water inlet and a water inlet joint; the plurality of water inlet joints (9) are all connected to the outlet of the electromagnetic multi-way control valve (20); the motor (14) is connected to the columnar cavity (8) for driving the rotation thereof.

2. The laser impact device for precisely spraying a uniform water confinement layer in a fixture according to claim 1, characterized in that: Nine 25×15 mm rectangular water spraying ports are evenly spaced on the water curtain nozzle assembly (7).

3. The laser impact device for precisely spraying a uniform water confinement layer in a fixture according to claim 1, characterized in that: A clamping piece (4) is arranged on the outside of the workpiece (6), a locking bolt (3) passes through the clamping piece (4) and is screwed onto the carrier (11), and the locking bolt (3) is adjusted to press the clamping piece (4) toward the workpiece (6), so that the workpiece (6) is locked in the receiving groove.

4. The laser impact device for precisely spraying a uniform water confinement layer in a fixture according to claim 1, characterized in that: The water curtain nozzle assembly (7) and the columnar cavity (8) are welded together as a whole, and the axial direction of the columnar cavity (8) is parallel to the workpiece (6).

5. The laser impact device for precisely spraying a uniform water confinement layer in a fixture according to claim 1, characterized in that: The control system (21) is connected to the laser (22), the industrial robot (19), the water pump (18), the electromagnetic multi-way control valve (20) and the motor (14).

6. The laser impact device for precisely spraying a uniform water confinement layer in a fixture according to claim 1, characterized in that: The motor (14) is fixed on the flange seat (15) via a fastening ring (16).

7. The laser impact device for precisely spraying a uniform water confinement layer in a fixture according to claim 1 or 6, characterized in that: The main shaft of the motor (14) is drivingly connected to the columnar cavity (8) via a shaft coupling (13).

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