Bulletproof plate laser cutting control method and cutting machine thereof

Abstract

The invention discloses a bulletproof plate laser cutting control method and a bulletproof plate laser cutting machine, and particularly relates to the technical field of bulletproof plate cutting, the bulletproof plate laser cutting machine comprises an equipment body, a laser head, multiple detectors, a driving mechanism and a controller, the multiple detectors are distributed on the side face of the laser head in a circumferential array mode, and the multiple detectors can form a detection area around the laser head; the coordinates of the surfaces of a plurality of bulletproof plates on the cutting path can be detected; the controller can preset a fitting curve of the curved surface of the bulletproof plate according to detection coordinates of the detector; the controller can preset the cutting path of the laser head according to the fitting curve, and the controller can control the movement of the driving mechanism and the rotation of the laser head according to the cutting path. The laser focus cannot always fall on the surface of the material; and when the laser vertically enters the inclined curved surface, the energy density per unit area is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of bulletproof plate cutting, and more specifically, to a bulletproof plate laser cutting control method and a cutting machine thereof. Background Art

[0002] Bulletproof plate is a key equipment that achieves ballistic protection through material and structural design. It mainly uses high-performance materials such as ultra-high molecular weight polyethylene fiber and ceramic composite materials, combined with a "ceramic panel + fiber backboard" composite structure. It can resist the impact energy of projectiles while ensuring lightweight. After the bulletproof plate is processed and formed, it is generally cut using a laser cutting machine.

[0003] However, bulletproof plates are generally curved plates designed according to ergonomics. When cutting curved surfaces, laser cutting machines may cause beam focusing problems because the laser head is usually designed for plane cutting and the laser focus position is fixed on the plane. When the surface height of the curved surface changes at different positions, the laser focus cannot always fall on the material surface, and the incision depth fluctuates, which will cause the local strength of the bulletproof plate to fail to meet the standard.

[0004] A Chinese patent with application number 202410235219.3 discloses a steel laser cutting machine. The invention sets a lifting mechanism at the four corners of a material stabilizing frame, allowing the steel placed on the material stabilizing frame to adjust its angle, thereby solving the problem that traditional laser cutting machines can only cut steel at a fixed angle and have a narrow range of application. However, when cutting bulletproof plates, the cutting path usually needs to match the size of the bulletproof plate, and a piece of material can usually cut multiple bulletproof plates. Therefore, it is necessary to adjust the angle multiple times for cutting, and it is inconvenient to change the cutting angle by adjusting the material stabilizing frame.

[0005] At the same time, when the laser beam has a certain angle with the irradiated surface, the light spot will become elliptical, the actual effective area will increase, and the energy density per unit area will decrease, which may lead to incomplete cutting. The steep area of ​​the curved surface may accumulate heat due to multiple reflections, resulting in material burning or performance degradation. Therefore, the present invention proposes a bulletproof plate laser cutting control method and a cutting machine thereof to solve the above problems. Summary of the invention

[0006] In order to overcome the above-mentioned defects of the prior art, the present invention provides a bulletproof plate laser cutting control method and a cutting machine thereof to solve the problems raised in the above-mentioned background technology.

[0007] To achieve the above object, the present invention provides the following technical solution: a control method for laser cutting of bulletproof plates, comprising the following steps: S1, periodically measuring the coordinates of multiple points on the surface of the bulletproof plate, analyzing the coordinates of the multiple points and selecting at least three key coordinates; S2. Calculate the center and radius of the arc that fits the local surface of the bulletproof plate according to the key coordinates, and calculate the fitting curve according to the center and radius; S3, calculating the coordinates and incident direction of the laser head when it is located at the point to be cut according to the fitting curve; S4, taking the coordinates of the multiple points to be cut and the incident direction as preset parameters, generating a parameter mapping table according to the preset parameters and presetting the cutting path according to the parameter mapping table; S5. Control the laser head to position and cut the bulletproof plate according to the cutting path.

[0008] Preferably, the curved surface of the bulletproof plate is divided into a plurality of independent curved surface segments, and local curved surface parameters are calculated independently for each segment to generate the fitting curve.

[0009] Preferably, in step S1, the coordinates of at least three points on the surface of the bulletproof plate are periodically measured, and the coordinates of the multiple points are coplanar with the coordinates of the points to be cut.

[0010] Preferably, the incident direction of the laser head is perpendicular to the tangent of the fitting curve at the point to be cut.

[0011] Preferably, the initial coordinates of the starting point of the cutting path are calculated according to the initial distance from the laser head to the bulletproof plate and the radius of the fitting curve.

[0012] Preferably, the deflection angle of the laser head is calculated according to the initial coordinates of the starting point of the cutting path and the incident direction.

[0013] Preferably, the cutting path is preset according to the deflection angle of the laser head and the initial distance from the laser head to the curved surface.

[0014] The present application also provides a cutting machine, which adopts the above-mentioned control method for laser cutting of bulletproof plates, including: an equipment body, a laser head, a detector, a driving mechanism and a controller; the laser head is arranged inside the equipment body, and the laser head is connected to the driving mechanism in a transmission manner for laser cutting the bulletproof plate; the detectors are multiple and distributed in a circumferential array on the side of the laser head, and the multiple detectors can form a detection area around the laser head to detect the coordinates of multiple points on the surface of the bulletproof plate; the controller is electrically connected to the detector, and the controller is used to calculate the fitting curve of the surface of the bulletproof plate according to the coordinates of the multiple points detected by the detector, and preset the cutting path of the laser head according to the fitting curve, and then control the driving mechanism to drive the laser head to move or rotate according to the cutting path to cut the bulletproof plate.

[0015] Preferably, one end of the laser head is fixedly connected to a fixing plate, one end of the fixing plate away from the laser head is fixedly connected to an electric push rod, the electric push rod is electrically connected to the controller, and the plurality of detectors are fixedly connected to the fixing plate.

[0016] Preferably, the controller is connected to the driving mechanism by electrical signals, and the controller can remotely control the driving mechanism to drive the laser head for positioning. A motor is fixedly connected to the side of the electric push rod, and one end of the motor is fixedly connected to a mounting plate. The mounting plate is transmission-connected to the driving mechanism, and the motor is connected to the controller by electrical signals.

[0017] Technical effects and advantages of the present invention: 1. The present invention controls the electric push rod according to the fitting curve and the initial distance D through a controller so that the laser head height follows the curvature change of the fitting curve during the cutting process, thereby ensuring that the focus of the laser head is always on the surface of the bulletproof plate, thereby preventing the laser focus from always falling on the material surface when the surface height at different positions of the curved surface changes, causing the incision depth to fluctuate, resulting in the problem that the local strength of the bulletproof plate does not meet the standard.

[0018] 2. The present invention makes the incident direction of the laser perpendicular to the direction of the tangent of the fitting curve at the cutting point, so as to prevent the laser from being incident vertically on the inclined surface, causing the light spot to become elliptical, the energy density per unit area to decrease, and the steep area of ​​the surface to accumulate heat due to multiple reflections, resulting in material burning or performance degradation.

[0019] 3. The present invention prevents data delays during cutting by the laser head and inaccurate incident angles and distances caused by different degrees of curvature at different positions of the bulletproof plate by presetting cutting parameters and refreshing fitting curve data in real time. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of the overall structure of the present invention.

[0021] Figure 2 This is a schematic diagram of the structure of the laser head of the present invention.

[0022] Figure 3 It is a schematic diagram of the coordinates of the curved surface detected by the detector of the present invention.

[0023] Figure 4 This is a schematic diagram of the fitting curve calculated by the controller of the present invention.

[0024] Figure 5 Schematic diagram of incident direction calculation for the controller of the present invention.

[0025] Figure 6 The figure is a flow chart of the control method of the controller of the present invention.

[0026] The accompanying drawings are marked as follows: 1. Equipment body; 2. Laser head; 21. Fixing plate; 22. Electric push rod; 23. Motor; 3. Detector; 4. Driving mechanism; 5. Controller. DETAILED DESCRIPTION

[0027] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] Example 1 In the actual production process, due to the change in surface height at different positions of the curved surface, the laser focus cannot always fall on the material surface, and the incision depth fluctuates, which will cause the local strength of the bulletproof insert to fail to meet the standard. This embodiment is specially invented to solve the above problem.

[0029] See also Figures 1 to 6 As shown, a control method for laser cutting of a bulletproof plate according to an embodiment of the present invention, the control method relates to a cutting machine, comprising: an equipment body 1, a laser head 2, a detector 3, a driving mechanism 4 and a controller 5; the laser head 2 is arranged inside the equipment body 1, and the laser head 2 is connected to the driving mechanism 4 for laser cutting of the bulletproof plate; the detectors 3 are multiple and circumferentially arrayed on the side of the laser head 2, and the multiple detectors 3 can form a detection area around the laser head 2 to detect the coordinates of multiple points on the surface of the bulletproof plate; the controller 5 is electrically connected to the detector 3, and the controller 5 is used to calculate the fitting curve of the surface of the bulletproof plate according to the coordinates of the multiple points detected by the detector 3, and preset the cutting path of the laser head 2 according to the fitting curve, and then control the driving mechanism 4 to drive the laser head 2 to move or rotate according to the cutting path to cut the bulletproof plate.

[0030] See also Figure 2 As shown, one end of the laser head 2 is fixedly connected to a fixing plate 21 , and the end of the fixing plate 21 away from the laser head 2 is fixedly connected to an electric push rod 22 , the electric push rod 22 is electrically connected to the controller 5 , and the multiple detectors 3 are all fixedly connected to the fixing plate 21 .

[0031] See also Figure 1 and Figure 2 As shown, the controller 5 is connected with the driving mechanism 4 by electrical signals. The controller 5 can remotely control the driving mechanism 4 to drive the laser head 2 to position. The side of the electric push rod 22 is fixedly connected with a motor 23. One end of the motor 23 is fixedly connected with a mounting plate. The mounting plate is transmission-connected with the driving mechanism 4. The motor 23 is connected with the controller 5 by electrical signals.

[0032] See also Figure 3 and Figure 4 As shown, the control method of laser cutting includes the following steps: S1. Periodically measure the coordinates of multiple points on the surface of the bulletproof plate, analyze the coordinates of the multiple points, and select at least three key coordinates; S2. Calculate the center and radius of the arc that fits the local surface of the bulletproof plate according to the key coordinates and calculate the fitting curve according to the center and radius; S3, calculating the coordinates and incident direction of the laser head when it is located at the point to be cut according to the fitting curve; S4, taking the coordinates of the multiple points to be cut and the incident direction as preset parameters, generating a parameter mapping table according to the preset parameters and presetting the cutting path according to the parameter mapping table; S5. Control the laser head to locate and cut the bulletproof plate according to the cutting path.

[0033] See also Figure 3 and Figure 4 As shown, the surface of the bulletproof plate is divided into multiple independent surface segments, and the local surface parameters of each segment are calculated independently to generate a fitting curve.

[0034] See also Figure 3 and Figure 4 As shown, in step S1, the coordinates of at least three points on the surface of the bulletproof plate are periodically measured, and the coordinates of the multiple points are coplanar with the coordinates of the points to be cut.

[0035] See also Figure 5 As shown, the incident direction of the laser head 2 is perpendicular to the tangent of the fitting curve at the point to be cut. The controller 5 calculates the initial coordinates of the starting point of the cutting path according to the initial distance from the laser head 2 to the bulletproof plate and the radius of the fitting curve, and calculates the deflection angle of the laser head 2 according to the initial coordinates of the starting point of the cutting path and the incident direction.

[0036] See also Figure 5 As shown, the controller 5 presets the cutting path according to the deflection angle of the laser head 2 and the initial distance from the laser head 2 to the curved surface.

[0037] When in use, the staff controls the driving mechanism 4 by operating the controller 5 to move the laser head 2 to the processing area, and controls the electric push rod 22 by the controller 5 to drive the laser head 2 to move so that the focus falls on the surface of the bulletproof plate. At this time, the controller 5 records the initial distance D between the laser head 2 and the bulletproof plate. During cutting, the detector 3 detects the surface coordinates of the bulletproof plate. When the detector 3 detects the surface coordinates of the bulletproof plate, the controller 5 calculates the center and radius of the curved surface of the bulletproof plate according to the detection parameters of the detector 3. For example, the detector 3 detects three coordinates, namely P 1 (x 1 ,y 1 )、P 2 (x 2 ,y2 )、P 3 (x 3 ,y 3 ), then by the following formula , , The coordinates of the center O (h, k) can be calculated. When the controller 5 calculates the coordinates of the center of the curved surface, the radius R of the curved surface can be calculated according to any detected coordinates. A curve fitting the curved surface can be obtained through the center O and the radius R. The controller 5 controls the electric push rod 22 according to the fitting curve and the initial distance D so that the height of the laser head 2 follows the curvature change of the fitting curve during the cutting process, thereby ensuring that the focus of the laser head 2 is always on the surface of the bulletproof plate, thereby preventing the laser focus from not always falling on the material surface when the surface height at different positions of the curved surface changes, causing the incision depth to fluctuate, resulting in the problem of substandard local strength of the bulletproof plate.

[0038] Example 2 In actual use, it is found that when the laser is incident vertically on an inclined surface, the light spot will become elliptical, the actual effective area will increase, and the energy density per unit area will decrease, which may result in incomplete cutting. The steep area of ​​the surface may accumulate heat due to multiple reflections, leading to material burning or performance degradation. Further improvements are made on the basis of the above embodiments.

[0039] On the basis of the above embodiment, when in use, the controller 5 calculates the coordinates of the to-be-cut point according to the fitting curve, and calculates the incident direction at the coordinates of the to-be-cut point according to the center O and radius R of the fitting curve. For example, when the coordinates of the to-be-cut point are P 1 (x 1 ,y 1 ), it can be calculated that the laser head 2 is located at P 1 The angle between the incident direction at the time and the initial incident direction, that is, the angle θ that the laser head 2 needs to deflect:

[0040] like Figure 5 As shown, after the controller 5 calculates the deflection angle θ, it calculates the cutting path of the laser head 2 according to the deflection angle θ and the initial distance D. The controller 5 controls the motor 23 to rotate according to the cutting path and controls the electric push rod 22 to move, so that the laser head 2 changes the incident direction and incident distance of the laser according to the curvature of the fitting curve during cutting, so that the incident direction of the laser is perpendicular to the direction of the tangent of the fitting curve at the cutting point, preventing the laser from becoming elliptical when it is incident vertically on the inclined surface, reducing the energy density per unit area, and the steep area of ​​the surface may accumulate heat due to multiple reflections, resulting in material burning or performance degradation.

[0041] Example 3 It was found in actual use that since the detector 3 and the controller 5 perform calculations while cutting is in progress, it is easy to cause data delay when the laser head 2 is cutting, and the degree of curvature at different positions of the bulletproof plate is different, which will cause the actual incident angle and distance of the laser during cutting to be inaccurate. Further improvements are made on the basis of the above embodiments.

[0042] When in use, multiple detectors 3 divide the curved surface of the bulletproof plate into several sections, and each section independently calculates the local curved surface parameters and presets the fitting curve through the controller 5. At the same time, during the movement of the laser head 2, the detector 3 moves synchronously while continuously detecting new coordinates and providing them to the controller 5 to calculate the fitting curve, thereby ensuring that during the cutting process, the data of the fitting curve is continuously detected and refreshed. The controller 5 uses the coordinates of multiple points to be cut and the incident direction in the fitting curve as preset parameters. The controller 5 uses the coordinates of each point to be cut in the preset parameters and its corresponding deflection angle as mapping parameters, and generates a mapping parameter table according to the multiple mapping parameters using the coordinate-angle mapping principle (the coordinate-angle mapping principle is to unify the spatial position and the rotation posture into executable processing parameters through geometric modeling and kinematic algorithms) and presets the cutting path according to the mapping parameter table, thereby ensuring that the controller 5 has calculated the parameters of the point to be cut before the laser head 2 moves to the point to be cut. By presetting the cutting parameters and refreshing the fitting curve data in real time, the data delay when the laser head 2 is cutting and the inaccurate incident angle and distance caused by the different degrees of the curved surface at different positions of the bulletproof plate are prevented.

[0043] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A control method for laser cutting of bulletproof plates, characterized in that: The following steps are involved: S1, periodically measuring the coordinates of multiple points on the surface of the bulletproof plate, analyzing the coordinates of the multiple points and selecting at least three key coordinates; S2. Calculate the center and radius of the arc that fits the local surface of the bulletproof plate according to the key coordinates, and calculate the fitting curve according to the center and radius; S3, calculating the coordinates and incident direction of the laser head when it is located at the point to be cut according to the fitting curve; S4, taking the coordinates of the multiple points to be cut and the incident direction as preset parameters, generating a parameter mapping table according to the preset parameters and presetting the cutting path according to the parameter mapping table; S5. Control the laser head to position and cut the bulletproof plate according to the cutting path.

2. The control method according to claim 1, characterized in that: The curved surface of the bulletproof plate is divided into a plurality of independent curved surface segments, and local curved surface parameters are calculated independently for each segment to generate the fitting curve.

3. The control method according to claim 1, characterized in that: In step S1, the coordinates of at least three points on the surface of the bulletproof plate are periodically measured, and the coordinates of the multiple points are coplanar with the coordinates of the points to be cut.

4. The control method according to claim 1, characterized in that: The incident direction of the laser head is perpendicular to the tangent line of the fitting curve at the point to be cut.

5. The control method according to claim 1, characterized in that: The initial coordinates of the starting point of the cutting path are calculated according to the initial distance from the laser head to the bulletproof plate and the radius of the fitting curve.

6. The control method according to claim 5, characterized in that: The deflection angle of the laser head is calculated according to the initial coordinates of the starting point of the cutting path and the incident direction.

7. The control method according to claim 6, characterized in that: The cutting path is preset according to the deflection angle of the laser head and the initial distance from the laser head to the curved surface.

8. A bulletproof plate laser cutting machine, using the control method according to any one of claims 1 to 7, characterized in that: It includes the equipment body, laser head, detector, driving mechanism and controller; The laser head is arranged inside the equipment body, and the laser head is transmission-connected with the driving mechanism for laser cutting the bulletproof plate; The detectors are multiple and circumferentially arrayed on the side of the laser head, and the multiple detectors can form a detection area around the laser head to detect the coordinates of multiple points on the surface of the bulletproof plate; The controller is connected to the detector by electrical signals. The controller is used to calculate the fitting curve of the bulletproof plate surface according to the coordinates of multiple points detected by the detector, and preset the cutting path of the laser head according to the fitting curve, and then control the driving mechanism to drive the laser head to move or rotate according to the cutting path to cut the bulletproof plate.

9. The bulletproof plate laser cutting machine according to claim 8, characterized in that: One end of the laser head is fixedly connected to a fixing plate, and one end of the fixing plate away from the laser head is fixedly connected to an electric push rod, the electric push rod is connected to the controller by electrical signals, and the plurality of detectors are fixedly connected to the fixing plate.

10. The bulletproof plate laser cutting machine according to claim 9, characterized in that: The controller is connected to the driving mechanism by electrical signals. The controller can remotely control the driving mechanism to drive the laser head for positioning. A motor is fixedly connected to the side of the electric push rod. One end of the motor is fixedly connected to a mounting plate. The mounting plate is transmission-connected to the driving mechanism. The motor is connected to the controller by electrical signals.

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