A laser following assisted pre-heating incremental forming apparatus and method

Abstract

The application discloses a laser following auxiliary preheating incremental forming device, which comprises a hanger, a forming tool head, a laser head, an angle adjusting knob and a rotary rocker. The forming tool head and the laser head are connected by the hanger and are respectively located on the two sides of a formed part. The laser head is fixed on the swing arm of the angle adjusting knob, and the angle adjusting knob is fixed on the swing arm of the rotary rocker. The rotary rocker controls the deflection direction and angle of the laser head. The application provides a simple and efficient control method for the rotation angle and rotation direction of the laser head, that is, the laser beam always preheats the processing track path point to improve the forming performance of the part. The laser heater and the forming tool head are synchronously driven, and no additional mechanical auxiliary device is needed. Meanwhile, the forming tool head and the laser heating device are arranged on the two sides of the plate, which facilitates the control of the heating angle of the laser and effectively avoids the interference between the laser beam and the tool head.

Description

Technical Field

[0001] This invention belongs to the field of progressive forming assisted processing technology, specifically relating to a laser-following assisted preheating progressive forming device and method. Background Technology

[0002] Incremental forming technology for sheet metal incorporates the layered manufacturing concept of rapid prototyping. It decomposes complex three-dimensional thin-walled parts into a series of contour lines, generating machining trajectories at each layer. Under computer control, the forming tool head processes the sheet metal layer by layer, performing successive local deformations instead of overall forming, ultimately shaping the sheet into the desired workpiece. Materials with poor overall ductility at room temperature (magnesium alloys, titanium alloys, etc.) and high-strength materials (high-strength steel, high-strength aluminum, etc.) are difficult to form using traditional incremental forming methods at room temperature. A combination of thermally assisted and incremental forming, known as thermal incremental forming, is typically used to improve the material's formability and machining accuracy. Thermal incremental forming methods can be divided into two strategies: overall heating and local heating. Overall heating involves heating the entire sheet metal to a high temperature, primarily using oil bath heating, hot air heating, and self-resistance electric heating. Local heating methods mainly include laser-assisted heating, friction heating, single-point electric heating, and halogen lamp heating. Laser-assisted heating progressive forming technology uses a high-energy-density laser beam as a heat source to irradiate the surface of a metal sheet, creating a temperature gradient in the thickness direction of the irradiated area. Under thermal stress, the sheet yields and undergoes plastic deformation. At the same time, the power of laser heating can be adjusted to meet the heating requirements of sheets of different thicknesses and materials, which is beneficial to improving the formability of progressive parts.

[0003] Currently, the equipment and process parameters required for laser-assisted progressive forming technology are quite complex, and most require additional mechanical devices to independently control the laser's movement. Some laser beam preheating devices also require special optical components for guidance, which complicates the forming process and reduces forming performance. Traditional laser-assisted thermal progressive forming technologies mostly fix the laser heating device on the spindle of the forming equipment, keeping it relatively stationary with the forming tool head for synchronous heating. This method easily causes interference between the laser beam and the sheet metal, failing to achieve the desired heating effect and resulting in poor forming performance. Alternatively, a cavity is machined in the center of the tool head, allowing the laser beam to pass through and heat the area being processed on the sheet metal. However, this method reduces the strength and rigidity of the tool head. When the tool head bends during forming, the laser beam cannot reach the sheet metal surface, affecting the progressive forming quality. Therefore, there is currently a lack of a progressive forming laser heating method that offers high heating efficiency, accurate heating range, and simple operation. Summary of the Invention

[0004] To address the aforementioned shortcomings of existing technologies, this invention proposes a laser-guided assisted preheating progressive forming apparatus and method.

[0005] This invention is achieved through the following technical solution:

[0006] A laser-guided preheating progressive forming device includes: a hanger (1), a forming tool head (2), a laser head (3), an angle adjustment knob (4), and a rotating rocker arm (5); the forming tool head (2) and the laser head (3) are connected by the hanger (1) and are located on both sides of the part respectively; the laser head (3) is fixed on the swing arm of the angle adjustment knob (4), and the angle adjustment knob (4) is fixed on the swing arm of the rotating rocker arm (5); the rotating rocker arm (5) controls the deflection direction and rotation angle of the laser head (3); the method for controlling the deflection direction and rotation angle of the laser head (3) is as follows:

[0007] (1) Perform three-dimensional modeling of the part. Arrange the path control points of the forming tool head clockwise from the outside to the inside on the surface of the model according to the principle of equal layer height and equal spacing. Obtain the spatial motion trajectory of the forming tool head and output the coordinates of the path control points in sequence. ;

[0008] (2) Project the path control points of the forming tool head in three-dimensional space onto the XY plane to generate a two-dimensional coordinate scatter plot of the forming tool head on the XY plane, and obtain the coordinates of the laser following heating control points. ;

[0009] (3) Based on the coordinates of the laser-following heating control point Obtain the coordinates of two adjacent control points The plane vectors formed And calculate the angle between two adjacent planar vectors to obtain the rotation angle of the joystick. :

[0010]

[0011] in, is the unit vector in the X-axis direction. ;

[0012] (4) Calculate the normal vector of the plane containing two adjacent planar vectors. And calculate the unit vector in the positive Z-axis direction. and spatial angle To obtain the deflection direction of the rotating joystick when the forming tool head moves to the next path control point;

[0013]

[0014]

[0015] Where the included angle When the angle is 0°, the joystick deflects clockwise in the positive direction; when the angle is... When the angle is 180°, the deflection direction of the joystick is negative and counterclockwise.

[0016] A method for controlling the deflection direction and rotation angle of a laser head in a laser-following assisted preheating progressive forming process, employing the aforementioned laser-following assisted preheating progressive forming device, includes the following steps:

[0017] (1) Perform three-dimensional modeling of the part. Arrange the path control points of the forming tool head clockwise from the outside to the inside on the surface of the model according to the principle of equal layer height and equal spacing. Obtain the spatial motion trajectory of the forming tool head and output the coordinates of the path control points in sequence. ;

[0018] (2) Project the path control points of the forming tool head in three-dimensional space onto the XY plane to generate a two-dimensional coordinate scatter plot of the forming tool head on the XY plane, and obtain the coordinates of the laser following heating control points. ;

[0019] (3) Based on the coordinates of the laser-following heating control point Obtain the coordinates of two adjacent control points The plane vectors formed And calculate the angle between two adjacent planar vectors to obtain the rotation angle of the joystick. :

[0020]

[0021] in, is the unit vector in the X-axis direction. ;

[0022] (4) Calculate the normal vector of the plane containing two adjacent planar vectors. And calculate the unit vector in the positive Z-axis direction. and spatial angle To obtain the deflection direction of the rotating joystick when the forming tool head moves to the next path control point;

[0023]

[0024]

[0025] Where the included angle When the angle is 0°, the joystick deflects clockwise in the positive direction; when the angle is... When the angle is 180°, the deflection direction of the joystick is negative and counterclockwise.

[0026] The laser-guided preheating progressive forming method employs the aforementioned technique. The motion trajectory parameters of the forming tool head, along with the rotation angle and deflection direction of the rotary rocker, are input into a CNC progressive forming machine. Before formal processing, the angle adjustment knob is manually adjusted to ensure the laser head's irradiation position is precisely at the next path control point of the forming tool head, and processing begins. During the forming process, as the laser head follows the movement of the forming tool head in the X, Y, and Z directions via the hanger, the rotation of the rotary rocker in the corresponding direction and angle is calculated and controlled to preheat the path control point. The laser head follows the movement of the forming tool head to heat the area to be formed, and the forming tool head completes layer-by-layer processing of the sheet metal along the generated tool path, thus completing the forming of the entire part.

[0027] This invention proposes a simple and efficient method for controlling the rotation angle and direction of a laser head, ensuring that the laser beam consistently preheats the processing path points to improve the forming performance of the parts. Furthermore, it achieves synchronous driving of the laser heater and the forming tool head, eliminating the need for additional mechanical auxiliary devices. Simultaneously, by placing the forming tool head and the laser heating device on opposite sides of the sheet metal, it facilitates control of the laser's heating angle and effectively prevents interference between the laser beam and the tool head. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of a laser-following heating device;

[0029] Figure 2 This is a schematic diagram of a frustum-shaped component.

[0030] Figure 3 A schematic diagram showing the three-dimensional motion trajectory of the frustum part, the arrangement of tool path points, and the rotation angle and direction of the rocker arm.

[0031] The attached diagram is labeled as follows: 1. Hanger, 2. Forming tool head, 3. Laser head, 4. Angle adjustment knob, 5. Rotary rocker arm, 6. Frustum part, 7. Path control point, 8. Laser follow-heat control point. Detailed Implementation

[0032] The present invention will be described in detail below with reference to specific embodiments.

[0033] like Figure 1 As shown, the laser-guided preheating progressive forming device includes: a bracket 1, a forming tool head 2, a laser head 3, an angle adjustment knob 4, and a rotating rocker arm 5. The forming tool head 2 and the laser head 3 are connected by the bracket 1 and are located on opposite sides of the part. The laser head 3 is fixed to the swing arm of the angle adjustment knob 4, which is in turn fixed to the swing arm of the rotating rocker arm 5. The rotating rocker arm 5 controls the deflection direction and rotation angle of the laser head 3.

[0034] like Figures 1-3 As shown, a laser-guided assisted preheating progressive forming method includes the following steps:

[0035] (1) Perform a three-dimensional model of the frustum part 6. Arrange the path control points of the forming tool head 2 clockwise from the outside to the inside on the surface of the frustum part 6 model according to the principle of equal layer height and equal spacing. Obtain the spatial motion trajectory of the forming tool head 2, and output the coordinates of the path control points 7 in sequence. .

[0036] (2) Project the path control point 7 of the forming tool head 2 in three-dimensional space onto the XY plane to generate a two-dimensional coordinate scatter plot of the forming tool head 2 on the XY plane, and obtain the coordinates of the laser following heating control point 8. .

[0037] (3) Based on the coordinates of laser-following heating control point 8 Obtain the coordinates of two adjacent control points The plane vectors formed And calculate the angle between two adjacent planar vectors to obtain the rotation angle of the laser-following heater rotating rocker 5. :

[0038]

[0039] in, is the unit vector in the X-axis direction. .

[0040] (4) Calculate the normal vector of the plane containing two adjacent planar vectors. And calculate the unit vector in the positive Z-axis direction. and spatial angle The direction of deflection of the joystick 5 is obtained when the forming tool head 2 moves to the next path control point 7.

[0041]

[0042]

[0043] Where the included angle When the angle is 0°, the rotation direction of the joystick 5 is clockwise; when the angle is... When the angle is 180°, the rotation direction of the joystick 5 is negative, counterclockwise.

[0044] (5) Input the machining program of the frustum part 6 and the deflection angle and direction of the rotating rocker arm 5 of the laser follower heater into the CNC progressive forming machine tool. Before the formal machining, manually adjust the angle adjustment knob 4 so that the irradiation position of the laser head 3 is just on the next path control point 7 of the forming tool head 2. Then start machining and keep the laser follower heater moving in the X, Y and Z directions through the hanger 1 with the movement of the forming tool head 2. At the same time, calculate and control the rotation of the rotating rocker arm 5 in the corresponding direction and angle through the program to achieve the purpose of preheating the path control point 7.

[0045] (6) The laser follower heater follows the movement of the forming tool head 2 to heat the area to be formed. The forming tool head 2 processes the sheet material layer by layer along the generated path control point 7 to complete the forming of the frustum part 6.

[0046] It should be understood that those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims.

Claims

1. A laser-guided assisted preheating progressive forming device, characterized in that, include: Hanger (1), forming tool head (2), laser head (3), angle adjustment knob (4), and rotary rocker (5); the forming tool head (2) and laser head (3) are connected by the hanger (1) and are located on both sides of the part respectively; the laser head (3) is fixed on the swing arm of the angle adjustment knob (4), and the angle adjustment knob (4) is fixed on the swing arm of the rotary rocker (5); the rotary rocker (5) controls the deflection direction and rotation angle of the laser head (3); the method for controlling the deflection direction and rotation angle of the laser head (3) is as follows: (1) Perform three-dimensional modeling of the part. Arrange the path control points of the forming tool head clockwise from the outside to the inside on the surface of the model according to the principle of equal layer height and equal spacing. Obtain the spatial motion trajectory of the forming tool head and output the coordinates of the path control points in sequence. ; (2) Project the path control points of the forming tool head in three-dimensional space onto the XY plane to generate a two-dimensional coordinate scatter plot of the forming tool head on the XY plane, and obtain the coordinates of the laser following heating control points. ; (3) Based on the coordinates of the laser-following heating control point Obtain the coordinates of two adjacent control points The plane vectors formed And calculate the angle between two adjacent planar vectors to obtain the rotation angle of the joystick. : ； in, is the unit vector in the X-axis direction. ; (4) Calculate the normal vector of the plane containing two adjacent planar vectors. And calculate the unit vector in the positive Z-axis direction. and spatial angle To obtain the deflection direction of the rotating joystick when the forming tool head moves to the next path control point; ； ； Where the included angle When the angle is 0°, the joystick deflects clockwise in the positive direction; when the angle is... When the angle is 180°, the deflection direction of the joystick is negative and counterclockwise.

2. A method for controlling the deflection direction and rotation angle of a laser head in a laser-guided assisted preheating progressive forming process, characterized in that, The laser-following assisted preheating progressive forming apparatus according to claim 1 includes the following steps: (1) Perform three-dimensional modeling of the part. Arrange the path control points of the forming tool head clockwise from the outside to the inside on the surface of the model according to the principle of equal layer height and equal spacing. Obtain the spatial motion trajectory of the forming tool head and output the coordinates of the path control points in sequence. ; (2) Project the path control points of the forming tool head in three-dimensional space onto the XY plane to generate a two-dimensional coordinate scatter plot of the forming tool head on the XY plane, and obtain the coordinates of the laser following heating control points. (3) Based on the coordinates of the laser-following heating control point Obtain the coordinates of two adjacent control points The plane vectors formed And calculate the angle between two adjacent planar vectors to obtain the rotation angle of the joystick. : ; in, is the unit vector in the X-axis direction. ; (4) Calculate the normal vector of the plane containing two adjacent planar vectors. And calculate the unit vector in the positive Z-axis direction. and spatial angle To obtain the deflection direction of the rotating joystick when the forming tool head moves to the next path control point; ； ； Where the included angle When the angle is 0°, the joystick deflects clockwise in the positive direction; when the angle is... When the angle is 180°, the deflection direction of the joystick is negative and counterclockwise.

3. The laser-following assisted preheating progressive forming method using the method described in claim 2, characterized in that, The motion trajectory parameters of the forming tool head, along with the rotation angle and deflection direction of the rotary rocker, are input into the CNC progressive forming machine. Before formal processing, the angle adjustment knob is manually adjusted so that the laser head's irradiation position is exactly at the next path control point of the forming tool head, and then processing begins. During the forming process, while the laser head moves along the X, Y, and Z directions with the forming tool head via the hanger, the rotation of the rotary rocker in the corresponding direction and angle is calculated and controlled to preheat the path control point. The laser head follows the movement of the forming tool head to heat the area to be formed, and the forming tool head completes layer-by-layer processing of the sheet metal along the generated tool path, completing the forming of the entire part.

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