Assembly and method for remote laser cutting of straps
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- APERAM
- Filing Date
- 2023-11-24
- Publication Date
- 2026-08-07
Smart Images
Figure CN122535475A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to an assembly for cutting at least one strap of a product, and an associated cutting method.
[0002] This invention is applicable to all packaged products with straps, especially rolls, packages, batches, and rings. It is particularly suitable for flat metal rolls. Background Technology
[0003] Typically, products are secured in packaging via strapping in the form of rolls, packages, batches, and rings.
[0004] This is especially true for sheet metal, particularly steel sheet metal, which is typically in the form of coils or packages (also known as stacks) and is bound together by one or more straps, also called bundles. These straps, for example, are made of plastic or metal and, by means of binding, allow the coil or package to maintain its shape. At the start of the production line, these straps need to be removed in order to unroll the coil or open the package.
[0005] Removing the strapping can be done manually by the operator. However, this operation is time-consuming and may pose a risk to the operator due to the elastic rebound of the strapping and / or roll material.
[0006] Mechanical devices for cutting strapping are also known, taking the form of a cutting tool robot that includes a strapping detection system and a pair of pliers suitable for cutting strapping.
[0007] However, this device has drawbacks. In practice, due to the tool's size limitations, the cutting tool is unsuitable for thick or overlapping straps. Similarly, when the straps are loosely bound to the roll material, the cutting tool may struggle to cut them. The same applies if the straps are too tight: the cutting tool cannot pass between the strap and the roll or bale. Furthermore, this device is expensive and requires a heavy and bulky hydraulic arm. This device cannot achieve rapid strap removal. Finally, there is a risk of damaging the surface of the roll or bale, such as causing scratches.
[0008] Therefore, the object of the present invention is to provide a cutting assembly that can quickly and safely remove the straps securing a product while limiting the risk of damaging the product. Summary of the Invention
[0009] Therefore, the present invention aims to provide a cutting assembly for cutting at least one strap of a product, such as a roll of flat metal, the strap having a thickness between 0.5 mm and 3 mm, the strap extending along its width between a first lateral edge and a second lateral edge, the cutting assembly comprising:
[0010] A cutting unit, configured to emit a laser beam focused on the strapping, includes: a laser suitable for emitting the beam; and an optical system configured to move and focus the laser beam received from the laser, such that the focused laser beam illuminates a continuous segment of the strapping from a first lateral edge to a second lateral edge.
[0011] - A control unit configured to detect the presence of the strapping and its position relative to the optical system, and, based on the detected position of the strapping, command the cutting unit to perform a series of cutting steps of at least two cutting steps on the continuous segment of the strapping, the control unit being configured to:
[0012] --The command instructs the cutting unit to perform a cutting scan on the continuous segment of the strap, the scan comprising emitting a focused laser beam from the first lateral edge to the second lateral edge of the strap, the focused laser beam being received on the continuous segment of the strap, each cutting scan ablating away one layer of the continuous segment of the strap, the thickness of which is at most 50% of the thickness of the strap.
[0013] --After performing the scan, the presence or absence of the strapping around the product is detected, and selectively, if the presence of the strapping is detected, an additional cutting step is performed, or if the absence of the strapping is detected, the series of cutting steps is interrupted.
[0014] The cutting assembly according to the invention enables rapid, safe, and precise cutting of the strapping by ablating a layer of limited thickness during each pass. This reduces the risk of product damage.
[0015] According to other advantageous aspects of the invention, the cutting component includes one or more of the following features, either individually or in combination of all technically possible features:
[0016] - The optical system includes a focusing device and a scanning device, the scanning device being configured to selectively deflect a laser beam emitted by the laser onto the focusing device, the focusing device being configured to focus the laser beam deflected by the scanning device onto a focal plane, the focal plane being perpendicular to the normal of the continuous segment of the strap and intersecting the continuous segment of the strap;
[0017] - The distance between the focusing device and the focal plane is greater than or equal to the width of the strap between the first lateral edge and the second lateral edge;
[0018] When the laser is suitable for emitting a pulsed laser beam, the optical system is configured to move and focus the pulsed laser beam received from the laser, such that the focused pulsed laser beam illuminates the continuous segment of the strap from the first lateral edge to the second lateral edge in the form of a plurality of adjacent light spots;
[0019] When the laser is suitable for emitting a continuous beam, the optical system is configured to move and focus the laser beam received from the laser such that the focused laser beam illuminates the continuous segment of the strap along a line extending from the first lateral edge of the strap to the second lateral edge.
[0020] - The scanning device includes a galvanometer scanner or a prism scanner;
[0021] - The focusing device includes at least one f-theta lens or plan lens or focusing mirror;
[0022] - The focusing device has a focal length greater than or equal to the width of the strap between the first lateral edge and the second lateral edge;
[0023] - The cutting unit further includes a moving device configured to move the optical system relative to the product in a direction orthogonal to the focal plane before each cutting step, such that the focal plane cuts the continuous segment of the strapping, and / or move the optical system relative to the product in a direction parallel to the strapping degree, the control unit being configured to command the moving device to move the optical system according to the detected strapping position;
[0024] - During each scan, the energy density received at each location of the continuous segment of the strap is suitable for ablating a layer of the strap, the thickness of which is at least 50 μm and at most equal to 50% of the thickness of the strap, particularly between 50 μm and 200 μm;
[0025] When the product is secured by at least two straps, the control unit is configured to detect the number of straps, the presence and position of each strap relative to the optical system, and, based on the detected position of each strap, command the cutting unit to perform a series of cutting steps of at least two cutting steps on consecutive segments of each strap. The control unit is configured to, in each cutting step:
[0026] - The cutting unit is commanded to perform a cutting scan on the continuous segments of each strap. For each detected strap, the scan successively includes emitting a focused laser beam from the first lateral edge to the second lateral edge of the strap, the focused laser beam being received on the continuous segments of the detected strap.
[0027] - After performing the scan, the presence or absence of each of the straps around the product is detected, and selectively, if at least one strap is detected, an additional cutting step is performed, or if no strap is detected, the series of cutting steps is interrupted.
[0028] - The cutting assembly also includes a protective housing adapted to accommodate at least a portion of the product during cutting;
[0029] - The cutting assembly also includes a collection module for collecting the strapping after it has been cut, the collection module being configured to grab the cut strapping and remove it from the product, particularly toward a storage container.
[0030] The present invention also relates to a method for cutting at least one strap of a fastening product using a cutting assembly of the type described above, the strap having a thickness between 0.5 mm and 3 mm, the strap extending along its width between a first transverse edge and a second transverse edge.
[0031] The cutting method includes a series of cutting steps, comprising the control unit detecting the position of the strap relative to the optical system, and, based on the detected position, performing at least two cutting steps on a continuous segment of the strap from the first lateral edge to the second lateral edge, each cutting step including:
[0032] - The control unit commands the cutting unit to perform a cutting scan on the continuous segments of the strapping.
[0033] - The cutting unit performs the cutting scan commanded by the control unit, including the laser emitting a laser beam and the optical system moving and focusing the laser beam such that, during the movement, the focused laser beam irradiates the continuous segment of the strap from the first lateral edge to the second lateral edge, and each cutting scan ablates the thickness of the continuous segment of the strap by a maximum of 50% of the strap thickness.
[0034] - After the cutting unit performs the scan, the detection unit detects whether the strapping is present or absent around the product, and
[0035] - Selectively, if the presence of the strap is detected, an additional cutting step is performed, or if the absence of the strap is detected, the series of cutting steps is interrupted.
[0036] According to other advantageous aspects of the invention, the cutting method includes one or more of the following features, considered individually or in combination of all technically possible aspects:
[0037] - The optical system includes a focusing device and a scanning device, the scanning device being configured to selectively deflect a laser beam emitted by the laser onto the focusing device, the focusing device being configured to focus the laser beam deflected by the scanning device onto a focal plane perpendicular to and intersecting the continuous segment of the strap, wherein during each scan, the laser beam emitted by the laser is selectively deflected by the scanning device so as to be focused by the focusing device, such that the focused laser beam illuminates the continuous segment of the strap from the first lateral edge to the second lateral edge;
[0038] - The distance between the focusing device and the product is greater than or equal to the width of the strap between the first lateral edge and the second lateral edge;
[0039] - When the laser emits a pulsed beam, the cutting scan includes emitting a focused pulsed laser beam from the first lateral edge to the second lateral edge of the strap, the focused pulsed laser beam being received on the continuous segment of the strap in the form of a plurality of adjacent light spots;
[0040] - When the laser emits a continuous beam, the cutting scan includes the laser emitting a continuous laser beam and the optical system moving and focusing the laser beam such that, during the movement, the focused laser beam illuminates the continuous segment of the strap along a line extending from the first lateral edge of the strap to the second lateral edge;
[0041] - The cutting method includes, before performing the series of cutting steps or before at least one cutting step, moving the optical system relative to the product in a direction orthogonal to the focal plane according to the detected strap position, such that the focal plane intersects the continuous segment of the strap, and / or moving relative to the product in a direction parallel to the width of the strap;
[0042] - During each scan, the energy density received at each location of the consecutive segments of the strap ablates a layer of the strap, the layer having a thickness of at least 50 μm and at most equal to 50% of the thickness of the strap, particularly between 50 μm and 200 μm;
[0043] - When the product is secured by at least two straps, the cutting method includes the control unit detecting the number of straps and the position of each strap relative to the optical system, and, based on the detected position of each strap, performing a series of cutting steps of at least two cutting steps on a continuous segment of each strap, each cutting step including:
[0044] --The control unit commands the cutting unit to perform a cutting scan on the continuous segments of each detected strap.
[0045] --The cutting scan, commanded by the control unit, is performed by the cutting unit, including emitting a laser beam by the laser and moving and focusing the laser beam by the optical system such that, during movement, the focused laser beam successively illuminates the detected consecutive segments of the strapping from the first lateral edge to the second lateral edge of each strapping.
[0046] --After the scanning is performed by the cutting unit, the detection unit detects whether each strap is present or absent around the product, and
[0047] --Optionally, if at least one strap is detected, an additional cutting step is performed, or if no strap is detected, the series of cutting steps is interrupted. Attached Figure Description
[0048] The invention will become more apparent from the following description, which is given by way of non-limiting example only and with reference to the accompanying drawings, in which:
[0049] [ Figure 1 ] Figure 1 This is a schematic diagram of a cutting assembly for cutting at least one strap according to an embodiment of the present invention;
[0050] [ Figure 2 ] Figure 2 yes Figure 1 Schematic diagram of the optical system for the cutting component;
[0051] [ Figure 3 ] Figure 3 yes Figure 1 A magnified view of the strapping area during the cutting process. Detailed Implementation
[0052] The cutting assembly 10 according to the invention is schematically shown in Figure 1 .
[0053] The cutting component 10 is designed to cut at least one strap 6 of the bundled package product 8.
[0054] In the following description, product 8 is a flat metal article 8 in the form of a coil 7.
[0055] In the variant, product 8 is in the form of a stack or package, such as a stack or package of sheets, or a ring, or any other form held by at least one strap.
[0056] exist Figure 1In this embodiment, the flat metal article 8 is a strip or sheet wound around itself, thereby forming a roll 7 that defines a central axis C, also referred to as a winding shaft. A transverse plane is defined in the roll 7, which is perpendicular to the central axis C of the roll 7.
[0057] Product 8 is made of steel, for example, supported by stainless steel. In variations, product 8 is made of non-metallic materials, such as plastic, composite materials, or wood.
[0058] The flat metal article 8 is held in the form of a roll 7 by means of at least one strap 6 that binds the roll 7.
[0059] The strap 6 is made of a material suitable for keeping the roll 7 in its coiled form.
[0060] For example, the strap 6 is made of plastic, preferably of polypropylene (PP), polyester (PE) and / or polyethylene terephthalate (PET).
[0061] In a variant, the strap 6 is made of metal, preferably carbon steel, stainless steel, aluminum and / or alloys, such as nickel-based or copper-based alloys.
[0062] When the strap 6 is not tightened, the strap 6 extends between the first longitudinal end and the second longitudinal end (not shown), extends between the first transverse edge 61 and the second transverse edge 62, and extends between a first surface 63, referred to as the inner surface, which is intended to contact the roll 7 when the strap 6 tightens the roll 7, and a second surface 64, referred to as the outer surface, which is opposite to the first surface 63.
[0063] For example, the strap 6 has a width L between 5 mm and 50 mm, measured between the first lateral edge 61 and the second lateral edge 62.
[0064] Typically, the strap 6 has a thickness e between 0.5 mm and 3.0 mm, measured between the first side 63 and the second side 64.
[0065] The straps 6 are held around the roll 7 by known fastening devices. For example, the ends of the straps 6 are secured to each other by welding, bonding, or using clips.
[0066] According to the first embodiment (shown in) Figure 1 The straps 6 circumferentially bind the roll 7 around its central axis C. Therefore, the straps 6 extend parallel to the transverse plane of the roll 7 and surround the roll 7.
[0067] In a variant (not shown), the straps 6 tighten a portion of the roll 7 by passing through its inner and outer sides. The straps 6 extend primarily in a direction parallel to the central axis C of the roll 7.
[0068] exist Figure 1 In the example, two straps 6 tighten the roll 7. The straps 6 may be identical, or made of different materials and / or have different sizes.
[0069] exist Figure 1 In the example, the two straps 6 extend generally parallel to each other and wrap around the central axis C of the roll 7.
[0070] In a variant (not shown), two straps 6 extend generally perpendicular to each other, with the first strap 6 encircling the roll 7 around the central axis C of the roll 7, and the second strap 6 encircling a portion of the roll 7 by passing through the inside and outside of the roll 7.
[0071] For example, one to twenty-five straps 6 tighten the roll material 7. The straps 6 may be the same or different, and may be arranged in various positions and arrangements that are obvious to those skilled in the art.
[0072] according to Figure 1 In the embodiment shown, the cutting assembly 10 includes a cutting unit 12 and a control unit 14.
[0073] The cutting unit 12 is configured to emit a laser beam 15 focused on the strap 6.
[0074] The cutting unit 12 includes a laser 16 suitable for emitting a beam, and an optical system 18 configured to move and focus the beam received from the laser 16 such that the focused beam illuminates the continuous segment 20 of the strap 6 from the first lateral edge 61 to the second lateral edge 62.
[0075] Here, "continuous strap section" means the section of strap 6 that extends between the first lateral edge 61 and the second lateral edge 62.
[0076] Laser 16 is suitable for emitting pulsed beams and / or continuous beams.
[0077] Laser 16 is, for example, a fiber laser.
[0078] Laser 16 is preferably adapted to emit a laser beam in the wavelength range of 200nm (ultraviolet radiation) to 2000nm (near-infrared radiation) and has an emission power between 50W and 10kW.
[0079] For example, laser 16 is a continuous-wave laser or a pulsed laser. For example, laser 16 is a continuous-wave laser with near-infrared emission, typically with a wavelength of 1070 nm and a power of 2 kW.
[0080] Preferably, the laser 16 further includes an optical fiber 161 configured to transmit radiation to an optical system 18, which is advantageously located at a distance, typically greater than 1 m.
[0081] The optical system 18 is configured to move and focus the beam received from the laser onto the irradiated area.
[0082] The optical system 18 includes a focusing device 22 and a scanning device 24, the scanning device being configured to selectively deflect a beam emitted by the laser 16 onto the focusing device 22.
[0083] Focusing device 22 is configured to focus the beam deflected by scanning device 24 onto... Figure 3 In the focal plane P shown, the focal plane P is perpendicular to the normal of segment 20 of strap 6.
[0084] The focusing device 22 is configured to focus the light beam deflected by the scanning device 24 onto a focal plane P that is perpendicular to the normal of the segment 20 of the strapping 6, the plane P being tangent to or intersecting the segment 20 of the strapping 6.
[0085] Preferably, the focal plane P intersects the segment 20 of the strap 6 such that the focal plane P is not only tangent to the outer surface 64 of the strap segment, but also located within the thickness of the segment.
[0086] Therefore, the energy density received at segment 20 of strap 6 is sufficient to achieve material ablation.
[0087] Preferably, the area of the beam 15 irradiating the continuous segment 20 of the strap 6 is between 10 μm and 100 μm.
[0088] Preferably, the focusing device 22 includes at least one f-theta lens, a flat lens, or a focusing lens.
[0089] Advantageously, the focusing device 22 has a focal length greater than or equal to the width L of the strap 6.
[0090] Therefore, the focusing device 22 is advantageously arranged at a distance d from the focal plane P, such that the distance d is greater than or equal to the width L of the strap 6.
[0091] For example, the distance d is between 5cm and 200cm.
[0092] The specified distance d enables cutting without having to be too close to the cutting surface as a conventional cutting head would. This reduces the risk of damage and sputtering onto the optical system.
[0093] The scanning device 24 is configured to selectively deflect the beam emitted by the laser 16 onto the focusing device 22 in order to move the irradiation area of the beam 15 focused on the strap 6.
[0094] Advantageously, the scanning device 24 is configured to deflect the beam received from the laser 16 to the focusing device 22 in response to a command to emit a focused beam at a given position on segment 20 of the strap 6, such that the beam 15, deflected and focused by the focusing device 22, illuminates the strap 6 at the given position. The emission command is preferably received from the control unit 14, as described below.
[0095] Preferably, the scanning device 24 is configured to move the focused beam 15 in the focal plane P along a first direction parallel to the width L of the strap 6. The beam then moves across the width of the strap 6.
[0096] Advantageously, the scanning device 24 is also configured to move the focused beam 15 in the focal plane P along a second direction orthogonal to and tangent to the segment 20 of the strap 6 width L. The beam then moves along the length of the strap 6.
[0097] The scanning device 24 is configured to move the beam at a speed of 0.1 m / s to 1000 m / s, for example, at a speed of 3 to 10 m / s.
[0098] Preferably, the scanning device 24 includes a galvanometer scanner 32.
[0099] The optical system 18, particularly the galvanometer scanner, is shown in more detail. Figure 2 middle.
[0100] The galvanometer scanner 32 includes a first mirror 320 mounted to be able to rotate about a first axis R1 relative to the focusing device 22, a second mirror 322 mounted to be able to rotate about a second axis R2 relative to the focusing device 22, the second axis R2 being orthogonal to the first axis R1, and a galvanometer motion device 324 for moving the first mirror and the second mirrors 320 and 322 about their respective first axis and second axis R1 and R2.
[0101] The rotation of the first movable mirror and the second movable mirror 320, 322 about their respective first axis and second axis R1, R2 is adapted to move the beam in two orthogonal directions in the focal plane P after the beam is focused by the focusing device 22, which is a lens, particularly along the width and length directions of the strap 6.
[0102] In a variant, the scanning device 24 includes a prism scanner.
[0103] Preferably, when the laser 16 emits a pulsed beam, the optical system 18 is configured to move and focus the pulsed beam received from the laser 16, such that the focused pulsed beam 15 illuminates the continuous segment 20 of the strap 6 from the first lateral edge 61 to the second lateral edge 62 in the form of a plurality of adjacent light spots.
[0104] In a variant, when the laser 16 emits a continuous beam of light, the optical system 18 is configured to move and focus the beam of light received from the laser 16 such that the focused beam 15 illuminates the continuous segment 20 of the strap 6 along a line extending from the first lateral edge 61 to the second lateral edge 62 of the strap 6.
[0105] During each scan, the energy density received at each location of segment 20 of strap 6 is suitable for ablating the layer of strap 6. Preferably, the layer has a thickness of at least 50 μm and at most equal to 50% of the thickness of strap 6, particularly between 50 μm and 200 μm.
[0106] Typically, the cutting unit 12 is configured to send a beam 15 with an energy density between 0.01 MW / cm² and 10 MW / cm² to the strapping section 20.
[0107] This creates a slit, also known as a cutting groove, on section 20 of the strap 6.
[0108] Preferably, such as Figure 1 As shown, the cutting unit 12 also includes a moving device 42 configured to move the optical system 18 relative to the roll 7 and the strapping 6 before each cutting step.
[0109] The moving device 42 is configured to move the position of the optical system 18 relative to the roll 7 in a direction orthogonal to the focal plane P, such that the focal plane P crosses the segment 20 of the strapping and / or moves in a direction parallel to the width L of the strapping 6.
[0110] Preferably, the control unit 14 is configured to command the moving device 42 to move the optical system 18 according to the detected strap position, as described below.
[0111] In the variant, the optical system 18 is fixed and includes, for example, adjustable motorizing elements adapted to modify parameters in the optical path to move the plane P so that it intersects with the continuous segment 20 of the strap 6.
[0112] The control unit 14 is configured to detect the presence of the strap 6 and the position of the strap 6 relative to the optical system 18, and, based on the detected position, command the cutting unit 12 to perform a series of cutting steps of cutting the continuous segments 20 of the strap 6 by at least two cutting steps.
[0113] In each cutting step, the control unit 14 is configured to command the cutting unit 12 to perform a cutting scan on the continuous segments 20 of the strapping 6, and after the scan is performed, to detect whether the strapping 6 is present around the roll 7, and selectively, if the presence of the strapping 6 is detected, to perform an additional cutting step, or if the absence of the strapping 6 is detected, to interrupt the series of cutting steps.
[0114] The cutting scan includes emitting a focused beam 15 from the first lateral edge 61 to the second lateral edge 62 of the strapping, the focused beam being received on the continuous segment 20 of the strapping 6, and the thickness of the layer of the continuous segment 20 of the strapping 6 ablated by each cutting scan being at most 50% of the strapping thickness.
[0115] The control unit 14 includes a strapping detection module 50 and a control module 52.
[0116] The detection module 50 is configured to detect the presence of the strap 6 and the position of the strap 6 relative to the optical system 18.
[0117] The detection module 50 includes an image acquisition system 54, such as including or connected to a camera 540, particularly a high-resolution camera.
[0118] Preferably, the detection module 50 further includes an illumination system (not shown) to improve image acquisition and position determination of the strap 6.
[0119] The detection module 50 also includes a processing system 56 configured to determine the position of the strap 6 relative to the optical system 18 based on each image acquired by the image acquisition system 54.
[0120] In a variant or additionally, the detection module 50 includes a laser system suitable for detecting the presence of the strap 6, for example, due to the height difference with the rest of the roll 7.
[0121] The control module 52 is configured to execute a series of cutting steps of the continuous segment 20 of the cutting strap 6, which consists of at least two cutting steps, according to the detected position command cutting unit 12, thereby producing a cutting slit.
[0122] Figure 3 The diagram schematically illustrates the irradiation of the cutting laser beam 15 at segment 20 of the strapping 6 to be cut.
[0123] Reference numeral 70 indicates the focal spot, which can be varied by changing the parameters of the focusing device 22. Reference numeral 34 indicates the obtained slit.
[0124] Advantageously, when the roll 8 is secured by at least two straps 6, such as Figure 1 As shown in the embodiment, the control unit 14 is configured to detect the number of straps, the presence of each strap 6, and the position of each strap 6 relative to the optical system 18, and, based on the detected position of each strap 6, command the cutting unit 12 to perform a series of cutting steps of cutting each continuous segment 20 of strap 6 in at least two cutting steps.
[0125] When two straps 6 appear simultaneously in the working area of the focusing device 22, the cutting unit 12 can cut the straps 6 simultaneously and / or cut them one by one.
[0126] In each cutting step, the control unit 14 is configured to command the cutting unit 12 to perform a cutting scan on each continuous segment 20 of the strap 6 via the control module 52. For each detected strap 6, the scan includes emitting a focused beam 15 sequentially from the first lateral edge 61 to the second lateral edge 62 of the strap 6, the focused beam being received onto the detected continuous segment 20 of the strap 6.
[0127] In each cutting step, the control unit 14 is also configured to detect whether each strap 6 is still present around the roll 7 after the scan is performed, and selectively, if at least one strap 6 is detected, to perform an additional cutting step, or if no strap 6 is detected, to interrupt the series of cutting steps.
[0128] According to a preferred embodiment, the cutting assembly 10 further includes a protective housing 80 adapted to accommodate at least a portion of the roll 7 during cutting. The protective housing 80 defines an internal volume V designed to accommodate at least a portion of the roll 7 during cutting.
[0129] The cutting unit 12 is preferably arranged in the internal volume V such that the beam 15 is located inside the housing 80, which serves as a laser protective housing.
[0130] The housing 80 also includes a dust extraction system 82 suitable for sucking up and expelling fumes and particles generated from the cutting process.
[0131] The housing 80 is suitable for accommodating the entire roll 7, for example, as shown in the image. Figure 1 As shown, or only a portion of the roll 7 may be contained, particularly the portion of the roll 7 containing the section 20 of the strap 6 to be cut. For example, the housing 80 may take the form of a cover, suitable for application onto the roll 7 and for covering the section 20 of the strap to be cut.
[0132] According to a preferred embodiment, the cutting assembly 10 further includes a collection module 90 for the strapping 6, adapted to collect the strapping 6 after it has been cut. The collection module 90 is configured to grip the cut strapping 6 and remove the cut strapping from the roll 7, particularly toward a storage container (not shown).
[0133] For example, the collection module 90 includes a movable arm equipped with a gripping device and a steering system for the movable arm.
[0134] The steering system for the movable boom includes elements for detecting the position of the cut strap 6, such as a camera, and control elements configured to command the movable boom according to the detected position of the cut strap 6, such that the gripping device grips the cut strap and conveys it to the storage container.
[0135] According to a variant, the movable boom includes a shearing mechanism configured to cut the strapping into shorter segments, typically 1 mm to 200 mm in length, for conveying the cut segments to a storage container. A control element is configured to command the movable boom based on a detected position of the cut strapping, causing a gripping device to grasp the cut strapping, and then the shearing mechanism to cut the strapping into shorter segments and convey these segments to the storage container.
[0136] According to a particular embodiment (not shown), the cutting assembly 10 also includes a traction system adapted to grip the strapping 6 and apply pressure to it, thereby removing it from the roll 7. The gripping system thus pulls the strapping 6 during cutting, facilitating the breakage of the strapping 6.
[0137] According to a preferred embodiment, the cutting assembly 10 further includes a holding system (not shown), such as a retaining roller, adapted to maintain the shape of the roll 7 when one or more straps 6 are cut.
[0138] A method for cutting at least one strap 6 according to the present invention will now be described.
[0139] The cutting method is implemented by the cutting component 10 according to the present invention.
[0140] The cutting method preferably includes a preparatory step of providing a roll 7 of flat metal articles 8, the roll including at least one strap 6 for binding the roll.
[0141] Preferably, a support system, such as retaining rollers, is arranged on or around the roll 7 to prevent it from suddenly unraveling after one or more straps 6 have been cut. In a variation, the roll 7 is arranged such that the free longitudinal edges of the roll 7 are prevented from suddenly unraveling under the weight of the roll 7.
[0142] During the detection step, the control unit 14, more specifically the detection module 50, detects the presence of at least one strap 6 and the position of the strap 6 relative to the optical system 18.
[0143] Based on the detected location, a series of cutting steps is performed to cut the continuous segment 20 of the strap 6 from the first lateral edge 61 to the second lateral edge 62 of the strap 6, involving at least two cutting steps.
[0144] Each cutting step includes a step in which the cutting unit 12 is commanded by the control unit 14, more specifically by the control module 52, to perform a cutting scan on the continuous segment 20 of the strapping 6, and a step in which the cutting unit 12 performs the cutting scan commanded by the control unit 14.
[0145] During the cutting and scanning step, laser 16 emits a beam.
[0146] Then, the optical system 18 moves and focuses the beam so that the focused beam 15 illuminates the continuous segment 20 of the strap 6 from the first lateral edge 61 to the second lateral edge 62.
[0147] The scanning device 24 thus selectively deflects the beam emitted by the laser 16 onto the focusing device 22. The focusing device 22 focuses the beam deflected by the scanning device 24 onto a focal plane P, which is perpendicular to the normal of the strapping segment 20 and intersects with the strapping segment 20.
[0148] In other words, during each scan, the beam emitted by the laser 16 is selectively deflected by the scanning device 24 so that it is focused by the focusing device 22, such that the focused beam 15 irradiates the strapping segment 20 from the first lateral edge 61 to the second lateral edge 62.
[0149] Preferably, the distance between the focusing device 22 and the strap 6 is greater than or equal to the width L of the strap 6.
[0150] During each cutting scan, the scanning device 24 moves the focused beam 15 in the focal plane P along at least one first direction that is substantially parallel to the width L of the strapping 6.
[0151] When the laser 16 emits a pulsed beam, the cutting scan includes emitting a focused pulsed beam from the first lateral edge 61 to the second lateral edge 62 of the strap 6, the focused pulsed beam being received on the continuous segment 20 of the strap 6 in the form of a plurality of adjacent light spots.
[0152] When the laser 16 emits a continuous beam, the cutting scan includes the laser 16 emitting a continuous beam and the optical system 18 moving and focusing the beam such that, during the movement, the focused beam illuminates a segment 20 of the strap along a line extending from the first lateral edge 61 to the second lateral edge 62 of the strap.
[0153] In each scan, the energy density received at each irradiation position ablates the layer of the strapping to a thickness of at least 50 μm and at most equal to 50% of the strapping thickness e, particularly a thickness between 50 μm and 200 μm.
[0154] Therefore, each cutting scan is suitable for ablation of a material layer of a continuous segment 20 of the strap with a thickness of up to 50% of the strap thickness e.
[0155] Therefore, beam 15 does not completely penetrate strap 6.
[0156] A slit, also known as a cutting groove, is formed on segment 20 of the strap 6. The depth of the slit is less than the thickness e of the strap 6, thereby limiting the risk of damaging the roll 7, especially the risk of forming scratches.
[0157] After the cutting unit 12 performs the scan, the detection module 50 detects whether the strapping 6 is still present around the roll material.
[0158] If strap 6 is detected, an additional cutting step is performed.
[0159] If the absence of strap 6 is detected, in other words, if the detection unit does not detect the strap, the cutting step series is interrupted.
[0160] Before performing a series of cutting steps or before at least one cutting step, preferably based on the detected position of the strap 6, the optical system 18 is moved relative to the roll 7 in a direction orthogonal to the focal plane P, such that the focal plane P intersects with the segment 20 of the strap 6.
[0161] Thus, the cutting unit 12 can cut the strapping 6 layer by layer, starting from the outer surface 64 until it is completely cut off. Therefore, since the energy emitted onto the strapping 6 is limited, the risk of damaging the roll material 7 is reduced.
[0162] Preferably, before performing a series of cutting steps or before at least one cutting step, the optical system 18 is moved relative to the roll 7 in a direction parallel to the width L of the strap, based on the detected position of the strap 6.
[0163] Preferably, when the strap 6 is made of plastic material, there is a cooling time for the strap 6 between each cutting step to limit the melting problem of the strap 6. The time is typically between 10 ms and 500 ms.
[0164] Advantageously, due to the stresses exerted on the strapping 6 by the roll 7 and the possible traction system, the strapping 6 is suitable to be broken by the cutting unit 12 before being completely cut across its entire thickness, particularly to its inner surface 63.
[0165] When the roll is secured by at least two straps 6, the method includes a series of cutting steps, including the control unit 12 detecting the number of straps 6 and the position of each strap 6 relative to the optical system 18, and performing at least two cutting steps to cut continuous segments 20 of each strap 6 based on the detected position of each strap 6.
[0166] When both straps 6 are simultaneously located within the working area of the focusing device 22, the straps 6 can be cut simultaneously or one at a time.
[0167] Each cutting step includes the control unit 14 commanding the cutting unit 12 to perform a cutting scan on each detected continuous segment 20 of the strap 6, and then the cutting unit 12 performing the cutting scan commanded by the control unit 14.
[0168] During the cutting scan, a laser beam is emitted by laser 16 and then moved and focused by optical system 18, such that during the movement, the focused beam 15 successively illuminates the detected continuous segments 20 of strap 6 from the first lateral edge 61 to the second lateral edge 62 of each strap 6.
[0169] At the end of the scanning process performed by the cutting unit, the control unit 14, and more specifically the detection module 50, detects whether each strap is still present around the roll 7.
[0170] If at least one strap 6 is detected, an additional cutting step is performed.
[0171] If the strapping is not detected, the cutting sequence is interrupted.
[0172] When component 10 includes a collection module 90 for the strapping 6, the collection module 90 grabs the cut strapping 6 and removes it from the roll 7, particularly toward the storage container (not shown).
[0173] Therefore, the cutting assembly 10 and cutting method according to the present invention can effectively and safely cut the straps 6 of the bundled material.
[0174] Therefore, cutting the strapping 6 does not require the operator to work near the roll 7, reducing the risk of injury.
[0175] Using remote laser cutting allows for fast and precise cutting of the strapping 6, thereby reducing the risk of damage to the roll material 7.
Claims
1. A cutting assembly (10) for cutting at least one strap (6) of a product (8), said product being, for example, a roll (7) of a flat metal article (8), said strap (6) having a thickness (e) between 0.5 mm and 3 mm, said strap (6) extending along a width (L) between a first lateral edge (61) and a second lateral edge (62), said cutting assembly (10) comprising: - A cutting unit (12), configured to emit a laser beam (15) focused on the strapping (6), the cutting unit comprising: Lasers suitable for emitting beams (16). An optical system (18) is configured to move and focus a laser beam received from the laser (16) such that the focused laser beam (15) illuminates a continuous segment (20) of the strap (6) from the first lateral edge (61) to the second lateral edge (62). - A control unit (14) is configured to detect the presence of the strapping (6) and the position of the strapping (6) relative to the optical system (18), and, based on the detected position of the strapping (6), command the cutting unit (12) to perform a series of cutting steps of at least two cutting steps on the continuous segment (20) of the strapping (6), wherein the control unit (14) is configured to: The cutting unit (12) is commanded to perform a cutting scan on the continuous segment (20) of the strap (6). The scan includes emitting a focused laser beam (15) from the first lateral edge (61) to the second lateral edge (62) of the strap (6). The focused laser beam is received on the continuous segment (20) of the strap (6). Each cutting scan ablates one layer of the continuous segment (20) of the strap (6), the thickness of which is at most 50% of the thickness (e) of the strap (6). After the scan is performed, the presence or absence of the strap (6) around the product (8) is detected, and selectively, if the presence of the strap (6) is detected, an additional cutting step is performed, or if the absence of the strap (6) is detected, the series of cutting steps is interrupted.
2. The cutting assembly (10) according to claim 1, characterized in that, The optical system (18) includes a focusing device (22) and a scanning device (24), the scanning device (24) being configured to selectively deflect a laser beam emitted by the laser (16) onto the focusing device (22), the focusing device (22) being configured to focus the laser beam deflected by the scanning device (24) onto a focal plane (P), the focal plane being perpendicular to the normal of the continuous segment of the strap (6) and intersecting the continuous segment (20) of the strap (6).
3. The cutting assembly (10) according to claim 2, characterized in that, The distance (d) between the focusing device (22) and the focal plane (P) is greater than or equal to the width (L) of the strap (6) between the first lateral edge (61) and the second lateral edge (62).
4. The cutting assembly (10) according to any one of claims 1 to 3, characterized in that, The laser (16) is suitable for emitting pulsed laser beams. The optical system (18) is configured to move and focus the pulsed laser beam received from the laser (16) such that the focused pulsed laser beam (15) illuminates the continuous segment (20) of the strap (6) from the first lateral edge (61) to the second lateral edge (62) of the strap (6) in the form of a plurality of adjacent light spots.
5. The cutting assembly (10) according to any one of claims 1 to 3, characterized in that, The laser (16) is suitable for emitting a continuous laser beam. The optical system (18) is configured to move and focus a laser beam received from the laser such that the focused laser beam (15) illuminates the continuous segment of the strap (6) along a line extending from the first lateral edge (61) of the strap (6) to the second lateral edge (62).
6. The cutting assembly (10) according to any one of claims 2 to 5, characterized in that, The scanning device (24) includes a galvanometer scanner (32) or a prism scanner.
7. The cutting assembly (10) according to any one of claims 2 to 6, characterized in that, The focusing device (22) includes at least one f-theta lens or flat lens or focusing lens.
8. The cutting assembly (10) according to any one of claims 2 to 7, characterized in that, The focusing device (22) has a focal length greater than or equal to the width (L) of the strap (6) between the first lateral edge (61) and the second lateral edge (62).
9. The cutting assembly (10) according to any one of claims 2 to 8, characterized in that, The cutting unit (12) further includes a moving device (42) configured to move the optical system (18) relative to the product (8) in a direction orthogonal to the focal plane (P) before each cutting step, such that the focal plane (P) cuts the continuous segment (20) of the strap (6), and / or move the optical system relative to the product in a direction parallel to the width of the strap (6), wherein the control unit (14) is configured to command the moving device (42) to move the optical system (18) according to the detected position of the strap (6).
10. The cutting assembly (10) according to any one of claims 1 to 9, characterized in that, During each scan, the energy density received at each position of the continuous segment (20) of the strap (6) is suitable for ablating a layer of the strap (6) with a thickness of at least 50 μm and at most equal to 50% of the thickness of the strap (6), particularly between 50 μm and 200 μm.
11. The cutting assembly (10) according to any one of claims 1 to 10, characterized in that, The product (8) is secured by at least two straps (6), and the control unit (14) is configured to detect the number of straps (6), the presence and position of each strap (6) relative to the optical system (18), and, based on the detected position of each strap (6), command the cutting unit (12) to perform a series of cutting steps of at least two cutting steps on consecutive segments (20) of each strap (6), wherein the control unit (14) is configured to: - The cutting unit (12) is commanded to perform a cutting scan on the continuous segment (20) of each strap (6). For each strap (6) detected, the scan successively includes emitting a focused laser beam (15) from the first lateral edge (61) to the second lateral edge (62) of the strap (6), the focused laser beam being received on the continuous segment (20) of the detected strap (6). - After the scan is performed, the presence or absence of each of the straps (6) around the product (8) is detected, and selectively, if at least one strap (6) is detected, an additional cutting step is performed, or if no strap (6) is detected, the series of cutting steps is interrupted.
12. The cutting assembly (10) according to any one of claims 1 to 11, characterized in that, The cutting assembly also includes a protective housing (80) adapted to accommodate at least a portion of the product (8) during cutting.
13. The cutting assembly (10) according to any one of claims 1 to 12, characterized in that, The cutting assembly also includes a collection module (90) for collecting the strapping (6) after it is cut, the collection module being configured to grab the cut strapping (6) and remove the cut strapping (6) from the product (8), particularly toward a storage container.
14. A cutting method for cutting at least one strap (6) of a fastening product (8) by means of a cutting assembly (10) according to any one of claims 1 to 13, wherein the strap (6) has a thickness (e) between 0.5 mm and 3 mm, and the strap (6) extends along a width (L) between a first lateral edge (61) and a second lateral edge (62). The cutting method includes a series of cutting steps, comprising the control unit (14) detecting the position of the strap (6) relative to the optical system (18), and, based on the detected position, performing at least two cutting steps on a continuous segment (20) of the strap (6) from the first lateral edge (61) to the second lateral edge (62) of the strap (6), each cutting step comprising: - The control unit (14) commands the cutting unit (12) to perform a cutting scan on the continuous segment (20) of the strap (6). - The cutting unit (12) performs the cutting scan commanded by the control unit (14), including the laser (16) emitting a laser beam and the optical system (18) moving and focusing the laser beam such that, during the movement, the focused laser beam (15) irradiates the continuous segment (20) of the strap (6) from the first lateral edge (61) to the second lateral edge (62), and each cutting scan ablates the thickness of the continuous segment (20) of the strap (6) by a maximum of 50% of the thickness (e) of the strap (6). - After the scanning is performed by the cutting unit (12), the detection unit (50) detects whether the strapping (6) is present or absent around the product (8), and - Selectively, if the presence of the strap (6) is detected, an additional cutting step is performed, or if the absence of the strap (6) is detected, the series of cutting steps is interrupted.
15. The cutting method according to claim 14, characterized in that, The optical system (18) includes a focusing device (22) and a scanning device (24). The scanning device (24) is configured to selectively deflect a laser beam emitted by the laser (16) onto the focusing device (22). The focusing device (22) is configured to focus the laser beam deflected by the scanning device (24) onto a focal plane (P) perpendicular to the normal of the continuous segment (20) of the strap (6) and intersecting the continuous segment (20) of the strap (6). During each scan, the laser beam emitted by the laser (16) is selectively deflected by the scanning device (24) so that it is focused by the focusing device (22) such that the focused laser beam illuminates the continuous segment of the strap (6) from the first lateral edge (61) to the second lateral edge (62).
16. The cutting method according to claim 15, characterized in that, The distance (d) between the focusing device (22) and the product (8) is greater than or equal to the width (L) of the strap (6) between the first lateral edge (61) and the second lateral edge (62).
17. The cutting method according to any one of claims 14 to 16, characterized in that, The laser (16) emits a pulsed laser beam. The cutting scan includes emitting a focused pulsed laser beam (15) from the first lateral edge (61) to the second lateral edge (62) of the strap (6), the focused pulsed laser beam being received on the continuous segment (20) of the strap (6) in the form of a plurality of adjacent light spots.
18. The cutting method according to any one of claims 14 to 16, characterized in that, The laser (16) emits a continuous laser beam. The cutting scan includes emitting a continuous laser beam by the laser (16) and moving and focusing the laser beam by the optical system (18) such that, during the movement, the focused laser beam (15) illuminates the continuous segment (20) of the strap (6) along a line extending from the first lateral edge (61) of the strap (6) to the second lateral edge (62).
19. The cutting method according to any one of claims 15 to 18, characterized in that, The cutting method includes, before performing the series of cutting steps or before at least one cutting step, moving the optical system (18) relative to the product (8) in a direction orthogonal to the focal plane (P) according to the detected position of the strap (6), such that the focal plane (P) intersects the continuous segment (20) of the strap (6), and / or moving relative to the product (8) in a direction parallel to the width (L) of the strap (6).
20. The cutting method according to any one of claims 14 to 19, characterized in that, During each scan, the energy density received at each position of the continuous segment (20) of the strap (6) ablates a layer of the strap (6) with a thickness of at least 50 μm and at most equal to 50% of the thickness (e) of the strap (6), particularly between 50 μm and 200 μm.
21. The cutting method according to any one of claims 14 to 20, characterized in that, The product (8) is secured by at least two straps (6), and the cutting method includes the control unit (14) detecting the number of straps (6) and the position of each strap (6) relative to the optical system (18), and, based on the detected position of each strap (6), performing a series of cutting steps of at least two cutting steps on consecutive segments (20) of each strap (6), each cutting step including: - The control unit (14) commands the cutting unit (12) to perform a cutting scan on the continuous segments (20) of each detected strap (6), The cutting unit (12) performs the cutting scan commanded by the control unit (14), including emitting a laser beam by the laser (16) and moving and focusing the laser beam by the optical system (18) such that, during the movement, the focused laser beam (15) successively illuminates the detected continuous segments (20) of the straps (6) from the first lateral edge (61) to the second lateral edge (62) of each strap (6). - After the scanning is performed by the cutting unit (12), the detection unit (50) detects whether each strap (6) is present or absent around the product (8), and -Optionally, if at least one strap (6) is detected, an additional cutting step is performed, or if no strap (6) is detected, the series of cutting steps is interrupted.