Non-contact laser slitting and heat sealing apparatus

Abstract

The present application relates to a kind of non-contact laser slitting heat sealing device.The device includes frame, frame is equipped with laser emitter, beam splitter, first, second galvanometer group, first, second focusing mirror, film conveying roller group, laser power controller, speed encoder and adaptive controller.Beam splitter is used to divide the laser beam into heat sealing beam and slitting beam.The first galvanometer group forms heat sealing zone on the film, and the second galvanometer group is used to control the scanning track of slitting beam, the scanning direction of slitting beam is the same as the scanning direction of the heat sealing beam, and the scanning track of slitting beam is located in the midline position of the width direction of the heat sealing zone.The present application patent is non-contact processing by using laser beam, which completely eliminates the mechanical contact between traditional hot cutting knife and film, fundamentally solves the problem of blade wear and sticking material, without frequent replacement of blade, greatly reduces maintenance cost and downtime.

Description

Technical Field

[0001] This invention relates to the field of heat sealing and slitting technology for plastic films, and specifically to a non-contact laser slitting and heat sealing device. Background Technology

[0002] In the production of plastic packaging bags, heat sealing and slitting are two core processes. Traditionally, heat sealing uses a heat-sealing blade to contact and heat the film, with the blade individually heated and its temperature controlled to achieve the seal through upward and downward compression. Heat cutting uses a movable mechanical heat-cutting blade for downward contact slitting. However, these heat sealing methods suffer from low temperature control precision. The heat-sealing blade relies on contact heat transfer, which exhibits significant response lag. Temperature fluctuations in the sealing area are typically above ±10°C. Excessive temperature causes over-melting of the film and brittleness in the sealing area, while insufficient temperature results in weak seals and defects such as incomplete or missed seals. Furthermore, the heat cutting method presents problems with blade wear and contamination. The mechanical blade inevitably generates wear debris during high-speed cutting of the film. This debris adheres to the film surface, affecting not only the sealing strength but also the product's appearance, potentially leading to finished product scrap. Additionally, the mechanical blade's contact with the film during heat cutting can cause plastic residue to adhere, which, as it accumulates, also impacts product quality. Therefore, a non-contact laser slitting and heat sealing device is needed to solve the above-mentioned technical problems. Summary of the Invention

[0003] The purpose of this invention is to provide a non-contact laser slitting and heat sealing device to solve the technical problems in the prior art where contact slitting and heat sealing methods easily lead to tool wear and plastic film adhesion, resulting in product quality issues.

[0004] To achieve the above objectives, the present invention provides a non-contact laser slitting and heat sealing device, which adopts the following technical solution: a non-contact laser slitting and heat sealing device, comprising a frame; A laser emitter, mounted on the frame, is used to emit a laser beam; A beam splitter, mounted on a frame and located in the output optical path of the laser emitter, is used to split the laser beam into a heat-sealed beam and a split beam; The first galvanometer group is mounted on the frame and located in the propagation optical path of the heat-sealing beam, and is used to control the scanning trajectory of the heat-sealing beam to form a heat-sealing area on the film; The second galvanometer group is mounted on the frame and located in the propagation optical path of the split beam, and is used to control the scanning trajectory of the split beam; the scanning direction of the split beam is the same as the scanning direction of the heat sealing beam, and the scanning trajectory of the split beam is located at the center line position in the width direction of the heat sealing area, dividing the heat sealing area into two independent sealing edges along the center line; The first focusing mirror is disposed on the outgoing light path of the first galvanometer group and is used to focus the heat-sealing beam into a medium power density focal spot to achieve molten heat sealing of the film sealing surface; The second focusing mirror is disposed on the outgoing light path of the second galvanometer group and is used to focus the slitting beam into a high power density focal spot to achieve the melting and slitting of the thin film. A film conveying roller assembly, mounted on the frame, is used to drive the film through the processing area at a set speed; A speed encoder is mounted on the film conveying roller assembly and is used to detect the rotational speed of the film conveying roller assembly. A laser power controller, connected to the laser emitter, is used to adjust the output power of the laser emitter; An adaptive controller is connected to the speed encoder, the laser power controller, the first galvanometer group, and the second galvanometer group, respectively, and is used to adjust the laser power, the galvanometer scanning speed, and the beam position in real time according to the thin film speed signal; and the adaptive controller controls the first galvanometer group and the second galvanometer group to scan synchronously.

[0005] The medium power density focal spot is circular with a diameter of 0.3~1.0 mm and a power density of 10. 2 ~10 3 W / mm 2 .

[0006] The high-power-density focal spot is circular with a diameter of 0.05~0.15mm and a power density of 10. 4 ~10 5 W / mm 2 .

[0007] The beam splitter includes a semi-transparent mirror and a reflector. The laser beam emitted by the laser emitter is split into a transmitted beam and a reflected beam after passing through the semi-transparent mirror. The transmitted beam, as a split beam, is reflected by the reflector and enters the second galvanometer group. The reflected beam, as a heat-sealed beam, enters the first galvanometer group. The installation angle of the semi-transparent mirror is adjustable to achieve an adjustable beam splitting ratio. The installation angle of the reflector is adjustable to change the propagation direction of the reflected beam.

[0008] The installation angle adjustment range of the semi-transparent and semi-reflective mirror is 0°~4°, corresponding to a power ratio of 60%~80% for the split beam and a power ratio of 20%~40% for the heat-sealed beam.

[0009] A first beam shaping element is provided on the propagation optical path of the heat-sealing beam, and a second beam shaping element is provided on the propagation optical path of the split beam; the first beam shaping element is used to shape the heat-sealing beam into a first linear beam, and the second beam shaping element is used to shape the split beam into a second linear beam; the first linear beam is focused by the first focusing lens to form a linear heat-sealing focal spot, and the second linear beam is focused by the second focusing lens to form a linear split focal spot.

[0010] The width of the linear heat-sealing scorch mark is 0.5 mm to 5 mm; the width of the linear slicing scorch mark is 0.05 mm to 0.15 mm.

[0011] The first beam shaping element and / or the second beam shaping element are Powell prisms or cylindrical lenses.

[0012] The beneficial effects of this invention are as follows: By setting a beam splitter, a single laser beam is divided into a heat-sealing beam and a slitting beam, which are then scanned synchronously by the first and second galvanometer groups. Furthermore, by setting different focusing lenses, the heat-sealing beam and the slitting beam achieve different power densities. The heat-sealing beam uses a medium power density to achieve melting and heat sealing of the film, while the slitting beam uses a high power density to achieve rapid melting and cutting of the film. The two functions do not interfere with each other and are completed collaboratively, resulting in stable and reliable processing quality. This invention patent, by using a laser beam for non-contact processing, completely eliminates the mechanical contact between the traditional hot-cutting blade and the film, fundamentally solving the problems of blade wear and material adhesion. It eliminates the need for frequent blade replacements, significantly reducing maintenance costs and downtime. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of a first embodiment of the non-contact laser cutting and heat sealing device of the present invention; Figure 2 yes Figure 1 A schematic diagram illustrating the principle; Figure 3 This is a schematic diagram of a second embodiment of the non-contact laser slitting and heat sealing device of the present invention; Figure 4 yes Figure 3 A schematic diagram illustrating the principle. Detailed Implementation

[0014] To facilitate understanding of the present invention, a more detailed description is provided below with reference to the accompanying drawings and specific embodiments. Preferred embodiments of the invention are shown in the drawings. However, the invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a thorough and complete understanding of the disclosure of the invention.

[0015] It should be noted that, unless otherwise defined, the technical and scientific terms used in this specification have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The use of "belonging" in this specification is for the purpose of describing particular embodiments only and is not intended to limit the invention.

[0016] An embodiment of the non-contact laser slitting and heat sealing device of the present invention is as follows: Figures 1-2 As shown, the system includes a frame 1, on which a laser emitter 2 is fixedly mounted for emitting a laser beam. In this embodiment, the laser emitter 2 is a CO2 laser with a wavelength of 9.3 μm to 10.6 μm and an output power of 30 W to 500 W. CO2 lasers have a high absorption rate for commonly used plastic films such as polyethylene and polypropylene, resulting in high processing efficiency. In other embodiments, the laser emitter may also be a fiber laser with a wavelength of 1.06 μm, or a laser with other wavelengths may be selected depending on the film material.

[0017] A beam splitter is installed on the frame 1, located in the output optical path of the laser emitter, to split the laser beam into a heat-sealing beam and a slit beam. In this embodiment, the beam splitter includes a semi-transparent mirror 7 and a reflector 8. The laser beam emitted by the laser emitter 2 is split into a transmitted beam 10 and a reflected beam 9 after passing through the semi-transparent mirror 7. The transmitted beam 10, as the slit beam, is reflected by the reflector 8 and enters the second galvanometer group 12, while the reflected beam 9, as the heat-sealing beam, enters the first galvanometer group 11. The installation angle of the semi-transparent mirror 7 is adjustable to achieve an adjustable beam splitting ratio. Specifically, the semi-transparent mirror 7 is mounted on the frame via a first optical frame 5. The installation angle of the semi-transparent mirror is adjustable from 0° to 4°, corresponding to a power ratio of 60% to 80% for the slit beam and 20% to 40% for the heat-sealing beam. The power ratio of the slit beam increases accordingly as the angle increases. Slitting requires higher power density to achieve rapid film melting, therefore a higher proportion of laser power is allocated; heat sealing requires appropriate power to ensure sealing quality but avoid over-melting, therefore a lower proportion of laser power is allocated. In this embodiment, the transmitted beam serves as the slitting beam and the reflected beam serves as the heat sealing beam. In other embodiments, the transmitted beam can also be used as the heat sealing beam and the reflected beam as the slitting beam, requiring only adjustment of the optical path layout. The beam splitter structure is not limited to a combination of a semi-transparent mirror and a reflecting mirror; a polarization beam splitter or a grating beam splitter can also be used.

[0018] The reflector 8 is mounted on the frame 1 via the second optical mount 6. The reflector is used to change the propagation direction of the transmitted beam from the semi-transparent mirror, ensuring it accurately enters the corresponding second galvanometer group 12. The mounting angle of the reflector is adjusted and fixed once during optical path debugging, and does not need to rotate synchronously with the semi-transparent mirror during operation. When the angle of the semi-transparent mirror changes due to the adjustment of the beam splitting ratio, the optical path alignment can be restored simply by adjusting the angle of the reflector alone. In this embodiment, both the first optical mount 5 and the second optical mount 6 are existing technologies, specifically using the EMHS series two-axis optical adjustment mount from Zolihan Optoelectronics Co., Ltd. Both mounts maintain the semi-transparent mirror and the reflector at an initial 45° angle during installation. In short, the aforementioned optical adjustment mount has the adjustment freedom to rotate around its first and second axes. By rotating the adjustment knob, the incident angle of the semi-transparent mirror can be changed, thereby adjusting the beam splitting ratio. The reflector has the same adjustment freedom and is used to compensate for optical path offset after adjusting the angle of the semi-transparent mirror. When the beam splitting ratio needs to be adjusted, firstly, rotate the adjustment knob of the first optical frame 5 to change the incident angle of the semi-transparent mirror 7 to the target angle; then rotate the adjustment knob of the second optical frame 6 to adjust the angle of the reflector 8, so that the split beam reflected by the reflector accurately enters the incident light path of the second galvanometer group 12. In this embodiment, a first mounting arm 3 and a second mounting arm 6 are provided on the frame 1 for corresponding installation of the first optical frame 5 and the second optical mirror 6.

[0019] A first galvanometer group 11 is mounted on the frame 1. The first galvanometer group 11 is located on the propagation optical path of the heat-sealing beam and is used to control the scanning trajectory of the heat-sealing beam to form a heat-sealing area on the film. The first galvanometer group is prior art, and its working principle and specific structure will not be described in detail in this embodiment. Simply put, the first galvanometer group includes a first X-axis galvanometer motor and a first Y-axis galvanometer motor. Through the coordinated movement of the two motors, two-dimensional scanning of the heat-sealing beam on the film surface is achieved. The scanning range of the first galvanometer group covers the processing area of ​​the heat-sealing region.

[0020] A second galvanometer group 12 is also provided on the frame 1, and the second galvanometer group is located on the propagation optical path of the slitting beam, used to control the scanning trajectory of the slitting beam. The second galvanometer group is prior art, and its working principle and specific structure will not be described in detail in this embodiment. Simply put, the second galvanometer group includes a second X-axis galvanometer motor and a second Y-axis galvanometer motor. Through the coordinated movement of the two motors, the slitting beam is used to achieve two-dimensional scanning of the film surface. The scanning direction of the slitting beam is the same as the scanning direction of the heat-sealing beam, and the scanning trajectory of the slitting beam is located at the center line of the width direction of the heat-sealing area 18, dividing the heat-sealing area along the center line into two independent sealing edges, the first sealing edge and the second sealing edge. The heat-sealing beam 16 scans along the sealing line direction, forming a heat-sealing area 18 (width W) with a certain width on the film 17; the slitting beam 15 scans synchronously along the center line of the heat-sealing area 18, dividing the heat-sealing area into two, forming the sealing edges of the two bags respectively, and the width of each sealing edge is approximately W / 2. The above settings achieve the processing effect of "one-time heat sealing and double-sided sealing", that is, after a heat-sealing area is cut, the sealing edges of two adjacent bags are formed at the same time.

[0021] A first focusing mirror 14 is disposed at the lower end of the first galvanometer group 11, and the first focusing mirror 14 is located in the output optical path of the first galvanometer group 11. It is used to focus the heat-sealing beam 16 into a medium-power density focal spot to achieve molten heat sealing of the film sealing surface. In this embodiment, the first focusing mirror 14 is an f-θ focusing mirror with a focal length of 100mm to 300mm. The f-θ focusing mirror ensures that the laser beam can be accurately focused on the same plane within the galvanometer scanning range, ensuring consistent processing quality. The focal spot diameter of the medium-power density focal spot is 0.3 to 1.0mm, and the power density is 10. 2 ~10 3 W / mm 2 This power density is sufficient to melt the film sealing surface without excessive vaporization, achieving a good heat-sealing effect. Specifically, the first focusing lens 14 is fixed coaxially in the output optical path of the first galvanometer group 11. The first focusing lens 14 is aligned with the optical path center of the first galvanometer group 11 and is used to focus the heat-sealing beam emitted from the first galvanometer group 11 onto the surface of the film 17. The first focusing lens 14 is installed at the light outlet of the first galvanometer group 11 via a threaded connection.

[0022] A second focusing mirror 13 is disposed at the lower end of the second galvanometer group 12, and the second focusing mirror 13 is located in the output optical path of the second galvanometer group 12. It is used to focus the split beam into a high-power-density focal spot to achieve thin film melting and splitting. In this embodiment, the second focusing mirror 13 is an f-θ focusing mirror with a focal length of 100mm to 300mm. The high-power-density focal spot has a focal spot diameter of 0.05 to 0.15mm and a power density of 102. 4 ~10 5 W / mm2 This power density allows the film to be heated to its vaporization temperature instantaneously, achieving rapid and clean melting and cutting with a smooth, burr-free cut. The focal lengths of the first and second focusing lenses can be the same or different. In this embodiment, the focal lengths of both the first and second focusing lenses are 200mm. Specifically, a second focusing lens 13 is fixed to the output optical path of the second galvanometer group 12 via coaxial mounting. The second focusing lens is aligned with the optical path center of the second galvanometer group and is used to focus the slit beam emitted from the second galvanometer group onto the heat-sealing area 18 on the surface of the film 17. The second focusing lens 13 is installed at the light outlet of the second galvanometer group 12 via a threaded connection. Since a smaller focal spot diameter is required to achieve a higher power density for the slit beam, the numerical aperture (NA2) of the second focusing lens 13 is greater than the numerical aperture (NA1) of the first focusing lens 14. Specifically, the ratio of the numerical aperture NA1 of the first focusing lens to the numerical aperture NA2 of the second focusing lens is 1:(3~10).

[0023] A film conveying roller assembly is installed on frame 1 to drive the film through the processing area at a set speed of 0.1 m / s to 3 m / s. The film conveying roller assembly includes a drive roller 19 and a driven roller 20. The drive roller is connected to a conveying drive motor (not shown in the figure), which drives the film to move forward continuously at the set speed. The film conveying direction is perpendicular to the scanning direction; that is, the film moves continuously longitudinally (length direction), while the laser beam scans laterally (width direction), forming a transverse heat-sealing area and slitting line on the film. A speed encoder is installed on the film conveying roller assembly, specifically on the shaft of the drive roller, to detect the rotational speed of the film conveying roller assembly. The speed encoder is connected to an adaptive controller, which detects the conveying speed in real time and transmits the speed signal to the adaptive controller. Specifically, the speed encoder can be an incremental encoder or an absolute encoder. A laser emitter is connected to a laser power controller to adjust the output power of the laser emitter. The laser power controller is also connected to the adaptive controller, which adjusts the output power of the laser emitter in real time according to the instructions of the adaptive controller.

[0024] In this embodiment, the adaptive controller is connected to the speed encoder, the laser power controller, the first X-axis galvanometer motor and the first Y-axis galvanometer motor of the first galvanometer group, and the second X-axis galvanometer motor and the second Y-axis galvanometer motor of the second galvanometer group, respectively. It is used to adjust the laser power, galvanometer scanning speed, and beam position in real time according to the thin film speed signal, and the adaptive controller controls the first and second galvanometer groups to scan synchronously. Synchronous scanning means that the two galvanometer groups start and end scanning simultaneously, and the scanning trajectory of the slit beam and the scanning trajectory of the heat-sealing beam maintain a constant relative positional relationship. The scanning positions of the first and second galvanometer groups are spaced apart along the thin film transport direction. Specifically, the scanning trajectory of the slit beam is always located at the centerline of the heat-sealing area formed by the heat-sealing beam, and the relative position between them is precisely guaranteed by the scanning control signal of the galvanometer group. The adaptive controller adjusts the laser power and galvanometer scanning speed in real time according to the thin film speed signal fed back by the speed encoder through an adaptive PID algorithm. When the film conveying speed increases, the irradiation time of the film per unit area receiving laser light decreases. The adaptive controller automatically increases the laser power or the galvanometer scanning speed to ensure the integrity of the scanning trajectory. When the film conveying speed decreases, the adaptive controller automatically reduces the laser power or the galvanometer scanning speed to avoid excessive energy input that could lead to over-melting or burn-through of the film. The initial parameters of the adaptive controller are preset according to the film material and thickness. The operation cycle of the adaptive controller is no greater than 10ms to ensure that the response time is no greater than 50ms, enabling timely response to speed changes and ensuring the stability of processing quality. In this embodiment, the scanning speed of the heat-sealing beam is 5m / s to 20m / s, and the scanning speed of the slitting beam is 5m / s to 15m / s. Experiments have verified that when the scanning speed of the slitting beam is 5~15m / s and the power density is 10... 4 ~10 5 W / mm 2 For common plastic films with a thickness ≤50μm (such as PE and PP), complete melting and cutting can be achieved in a single scan. The scanning speed of the slitting beam can be the same as or different from that of the heat sealing beam, depending on the power density and processing requirements.

[0025] The control logic of the above adaptive controller is as follows: (1) Signal acquisition: The speed encoder acquires the rotational speed signal of the film conveying roller group in real time and converts it into the linear velocity signal V(t) of the film; (2) Parameter calculation: The adaptive controller calculates the laser energy density required per unit area of ​​the thin film E0 = P(t) / [V(t) × Ws] based on the current thin film linear velocity V(t), where P(t) is the laser output power and Ws is the focal spot width (the focal spot diameter is taken when the focal spot is circular). When V(t) increases, in order to ensure that E0 is constant, P(t) needs to be increased accordingly or the galvanometer scanning speed needs to be increased. However, when V(t) is greater than the preset threshold Vmin (e.g., 0.01m / s), the above formula is used for calculation. When V(t) is less than Vmin, the laser emitter stops emitting light or switches to standby mode. (3) PID control: The adaptive controller adopts a single neuron adaptive PID algorithm, taking the deviation e(t) between the target energy density Er and the actual energy density Et as input, and adjusts the proportional, integral and derivative coefficients online through supervised Hebb learning rules, and outputs laser power control signal and galvanometer scanning speed control signal; (4) Synchronization control: The adaptive controller simultaneously sends synchronous scanning signals to the first galvanometer group and the second galvanometer group to ensure that the scanning start time, scanning speed and relative position of the scanning trajectory of the two galvanometer groups are consistent; (5) Position Compensation: The adaptive controller calculates the deflection angle θ = arctan(V(t) / Vscan) of the scanning trajectory of the heat-sealing beam and the slitting beam based on the instantaneous linear velocity V(t) of the thin film, where Vscan is the galvanometer scanning velocity of the corresponding beam. This causes the scanning trajectory of the laser beam to tilt accordingly with the direction of the thin film's movement, compensating for the beam landing point position offset caused by the continuous movement of the thin film and ensuring that the scanning trajectory of the slitting beam is always located at the centerline position in the width direction of the heat-sealing area. When the film velocity fluctuates, the controller updates the θ value in real time according to the velocity change ΔV to achieve dynamic tracking compensation.

[0026] In operation, the non-contact laser slitting and heat-sealing device of this invention uses a film conveying roller group to drive the film through the processing area at a set speed. During the film's movement, the first and second galvanometer groups simultaneously scan to complete heat sealing and slitting, eliminating the need for the film to stop or decelerate during processing. Because the laser scanning speed is significantly greater than the film conveying speed, the film's displacement along the conveying direction is much smaller than the width of the heat-sealing zone within a single scanning cycle. Therefore, even with continuous film movement, the laser can still form a precise heat-sealing zone and slitting line at a predetermined position on the film surface. When the film conveying speed changes, the speed encoder detects the speed change in real time and transmits the signal to the adaptive controller. The adaptive controller uses an adaptive PID algorithm to adjust the laser power and scanning speed in real time, keeping the laser energy input per unit area of ​​film constant. Simultaneously, it dynamically adjusts the deflection angle of the scanning trajectory to compensate for positional offsets caused by film movement, ensuring the slitting line is always located at the centerline of the heat-sealing zone's width direction. Compared to the traditional intermittent working mode (film forward → stop → process → forward again), the continuous operation mode of this invention eliminates tension fluctuations and positional deviations caused by frequent starts and stops, significantly improving production efficiency and processing accuracy.

[0027] In this embodiment, the adaptive controller 13 incorporates an adaptive PID controller, preferably a single-neuron adaptive PID controller, which uses fuzzy set theory to achieve online adjustment of the learning rates of the proportional, integral, and derivative coefficients. This algorithm exhibits good anti-interference capability, adaptive capability, and self-adjusting capability.

[0028] The non-contact laser slitting and heat sealing device of the present invention, when in use: Driven by a set speed, the film passes through the processing area via a film conveying roller assembly. A speed encoder detects the film's conveying speed in real time and transmits the speed signal to an adaptive controller. A laser emitter emits a laser beam, which is split into a heat-sealing beam and a slitting beam by a beam splitter. The heat-sealing beam, controlled by a first galvanometer group and focused into a medium-power-density focal spot by a first focusing lens, irradiates the sealing area of ​​the film, melting and heat-sealing the film's sealing surface to form a heat-sealed area of ​​a certain width. Simultaneously, the slitting beam, controlled by a second galvanometer group and focused into a high-power-density focal spot by a second focusing lens, irradiates the centerline of the heat-sealed area along its width, dividing the heat-sealed area into two independent sealing edges: a first sealing edge and a second sealing edge. The scanning direction of the slitting beam is the same as that of the heat-sealing beam, and both scan synchronously under the control of the adaptive controller. Based on the speed signal fed back by the speed encoder, the adaptive controller adjusts the laser power and galvanometer scanning speed in real time using an adaptive PID algorithm to maintain a constant laser energy input per unit area of ​​the film. After processing, the finished bag is discharged by the discharge mechanism (not shown in the figure), and the waste is collected by the waste recycling system (not shown in the figure). The discharge mechanism and the waste recycling system are both existing technologies, and their structures will not be described in detail in this embodiment.

[0029] In the foregoing description of this specification, unless otherwise expressly specified and limited, the terms "fixed," "installed," "connected," or "linked" should be interpreted broadly. For example, the term "linked" can refer to a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; or it can refer to the internal communication of two components or the interaction between two components. Therefore, unless otherwise expressly limited in this specification, those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0030] Based on the above description in this specification, those skilled in the art will also understand that the following terms used, such as "upper," "lower," "front," "rear," "left," "right," "length," "width," "thickness," "vertical," "horizontal," "top," "bottom," "inner," "outer," "axial," "radial," "circumferential," "center," "longitudinal," and "transverse," are terms indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings of this specification. They are only for the purpose of facilitating the explanation of the present invention and simplifying the description, and do not explicitly or implicitly suggest that the device or element involved must have the specific orientation, or be constructed and operated in a specific orientation. Therefore, the above-mentioned orientation or positional relationship terms should not be understood or interpreted as limitations on the present invention.

[0031] Furthermore, the terms "first" or "second," etc., used in this specification to refer to numbers or ordinal numbers are for descriptive purposes only and should not be construed as indicating, explicitly or implicitly, relative importance or specifying the number of indicated technical features. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this specification, "a plurality of" means at least two, such as two, three, or more, unless otherwise explicitly specified.

[0032] A second embodiment of the non-contact laser slitting and heat sealing device of the present invention, as follows: Figure 3-4 As shown, the difference from Embodiment 1 is that a linear focal spot scheme is also provided. A first beam shaping element 22 is provided in the propagation optical path of the heat-sealed beam, and a second beam shaping element 21 is provided in the propagation optical path of the split beam. The first beam shaping element 22 and the second beam shaping element 21 are respectively fixed to the optical path by their respective mirror mounts and are located between the galvanometer group and the focusing lens. Specifically, the first beam shaping element 22 is fixed to the optical path between the first galvanometer group 11 and the first focusing lens 14 by the first mirror mount, and the second beam shaping element 21 is fixed to the optical path between the second galvanometer group 12 and the second focusing lens 13 by the second mirror mount. Each mirror mount is provided with an adjusting screw for adjusting the angle and position of the beam shaping element. All mirror mounts are existing technology and can adopt the EMHS series two-axis optical adjustment frame of Zolihan Optoelectronics Co., Ltd. mentioned above.

[0033] The first beam shaping element 22 shapes the circular heat-sealing beam into a first linear beam, and the second beam shaping element 21 shapes the circular slitting beam into a second linear beam. After being focused by the first focusing lens 14, the first linear beam forms a linear heat-sealing focal spot on the surface of the film 17, with a width of 1 mm. After being focused by the second focusing lens 13, the second linear beam forms a linear slitting focal spot on the surface of the film 17, with a width of 0.1 mm. The width direction of the linear focal spot is consistent with the width direction of the heat-sealing area, and the length direction is consistent with the scanning direction. During processing, the linear heat-sealing focal spot scans once along the sealing line direction to complete the heating of the entire heat-sealing line; the linear slitting focal spot scans once along the centerline direction of the heat-sealing area to complete the cutting of the entire slitting line. Compared to the point-by-point scanning of the circular focal spot, the linear focal spot covers the entire processing line in one scan, offering advantages such as higher efficiency and more uniform heating. The first beam shaping element 22 and the second beam shaping element 21 are Powell prisms or cylindrical lenses. A Powell prism can convert a laser beam into a straight line with uniform energy distribution along the entire line, producing a linear light spot with more uniform energy distribution. In other embodiments, the first beam shaping element and the second beam shaping element can also be cylindrical lenses.

Claims

1. A non-contact laser slitting and heat-sealing device, characterized in that: Including racks; A laser emitter, mounted on the frame, is used to emit a laser beam; A beam splitter, mounted on a frame and located in the output optical path of the laser emitter, is used to split the laser beam into a heat-sealed beam and a split beam; The first galvanometer group is mounted on the frame and located in the propagation optical path of the heat-sealing beam, and is used to control the scanning trajectory of the heat-sealing beam to form a heat-sealing area on the film; The second galvanometer group is mounted on the frame and located in the propagation optical path of the split beam, and is used to control the scanning trajectory of the split beam; the scanning direction of the split beam is the same as the scanning direction of the heat sealing beam, and the scanning trajectory of the split beam is located at the center line position in the width direction of the heat sealing area, dividing the heat sealing area into two independent sealing edges along the center line; The first focusing mirror is disposed on the outgoing light path of the first galvanometer group and is used to focus the heat-sealing beam into a medium power density focal spot to achieve molten heat sealing of the film sealing surface; The second focusing mirror is disposed on the outgoing light path of the second galvanometer group and is used to focus the slitting beam into a high power density focal spot to achieve the melting and slitting of the thin film. A film conveying roller assembly, mounted on the frame, is used to drive the film through the processing area at a set speed; A speed encoder is mounted on the film conveying roller assembly and is used to detect the rotational speed of the film conveying roller assembly. A laser power controller, connected to the laser emitter, is used to adjust the output power of the laser emitter; An adaptive controller is connected to the speed encoder, the laser power controller, the first galvanometer group, and the second galvanometer group, respectively, and is used to adjust the laser power, the galvanometer scanning speed, and the beam position in real time according to the thin film speed signal; and the adaptive controller controls the first galvanometer group and the second galvanometer group to scan synchronously.

2. The non-contact laser slitting and heat sealing device according to claim 1, characterized in that: The medium power density focal spot is circular with a diameter of 0.3~1.0 mm and a power density of 10. 2 ~10 3 W / mm 2 .

3. The non-contact laser slitting and heat sealing device according to claim 1, characterized in that: The high-power-density focal spot is circular with a diameter of 0.05~0.15mm and a power density of 10. 4 ~10 5 W / mm 2 .

4. The non-contact laser slitting and heat sealing device according to claim 1, characterized in that: The beam splitter includes a semi-transparent mirror and a reflector. The laser beam emitted by the laser emitter is split into a transmitted beam and a reflected beam after passing through the semi-transparent mirror. The transmitted beam, as a split beam, is reflected by the reflector and enters the second galvanometer group. The reflected beam, as a heat-sealed beam, enters the first galvanometer group. The installation angle of the semi-transparent mirror is adjustable to achieve an adjustable beam splitting ratio. The installation angle of the reflector is adjustable to change the propagation direction of the reflected beam.

5. The non-contact laser slitting and heat sealing device according to claim 4, characterized in that: The installation angle adjustment range of the semi-transparent and semi-reflective mirror is 0°~4°, corresponding to a power ratio of 60%~80% for the split beam and a power ratio of 20%~40% for the heat-sealed beam.

6. The non-contact laser slitting and heat sealing device according to claim 1, characterized in that: A first beam shaping element is provided on the propagation optical path of the heat-sealing beam, and a second beam shaping element is provided on the propagation optical path of the split beam; the first beam shaping element is used to shape the heat-sealing beam into a first linear beam, and the second beam shaping element is used to shape the split beam into a second linear beam; the first linear beam is focused by the first focusing lens to form a linear heat-sealing focal spot, and the second linear beam is focused by the second focusing lens to form a linear split focal spot.

7. The non-contact laser slitting and heat sealing device according to claim 6, characterized in that: The width of the linear heat-sealing scorch mark is 0.5 mm to 5 mm; the width of the linear slicing scorch mark is 0.05 mm to 0.15 mm.

8. The non-contact laser slitting and heat sealing device according to claim 6, characterized in that: The first beam shaping element and / or the second beam shaping element are Powell prisms or cylindrical lenses.

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