Pipe and profile machining machine with a system for scanning the profile of the cross section of the pipe or profile being machined

Abstract

A pipe and profile machining machine having a system for scanning a profile of a cross section of a pipe or profile to be machined is described, the machine comprising a machining head, a feed device arranged to move the pipe or profile to be machined each time forward along a feed axis towards the machining head, and a scanning system for scanning a profile of a cross section of the pipe or profile to be machined. The scanning system comprises at least one laser scanning module having a laser emitter arranged to emit a light blade with which at least one portion of the pipe or profile to be machined is illuminated, the laser scanning module having a camera arranged to acquire an image of the portion of the pipe or profile to be machined illuminated by said light blade. The camera comprises a lens system and a sensor configured in such a way that the optical axis of the camera is tilted at an angle with respect to the direction normal to the sensor plane of the sensor to the light blade generated by the laser emitter, bringing the focal plane to a position as coincident as possible with the plane of the light blade according to the Scheimpflug principle.

Description

Technical Field

[0001] This invention generally relates to machines for processing pipes and profiles, particularly machines for laser processing (e.g., laser cutting) of pipes and profiles, the machines being equipped with a scanning system for scanning the outline of the cross-section of the pipe or profile being processed.

[0002] In the following description and claims, the terms “tube” and “profile” are used to indicate any elongated product having a uniform (other than machining tolerances) cross section along its longitudinal axis, wherein the cross section can be of any shape, whether closed (e.g., circle, rectangle, square, etc.) or open (e.g., L, C, U, etc.). Background Technology

[0003] It is known that scanning systems are used on machines used for laser processing of pipes and profiles in order to detect the geometry of the cross-section of the pipe or profile being processed.

[0004] Specifically, scanning systems are known to include pairs of laser scanning modules (LSMs), each LSM comprising a laser emitter capable of emitting a light blade onto the pipe or profile being processed and a camera capable of acquiring an image of a portion of the pipe or profile being processed, the portion of which is illuminated by the light blade emitted by the associated laser emitter; and a processing unit capable of processing the images acquired by the camera of each LSM to reconstruct all or at least part of the profile of the cross-section of the pipe or profile being processed. Due to the use of such a scanning system, the actual profile of the cross-section of the pipe or profile being processed can be known at any time, and the actual profile may differ more or less significantly from the theoretical profile due to machining tolerances. Therefore, it is possible to determine the center of the processing operation being performed based on the actual profile of the cross-section of the pipe or profile being processed.

[0005] Examples of machines for laser processing of pipes and profiles, including such scanning systems, are known in the name of the applicant from EP3233366.

[0006] According to this known scheme, the machine includes a laser processing head arranged to emit a focused laser beam onto the surface of a tube or profile to be processed, and a scanning system arranged to scan the profile of the cross-section of the tube or profile to be processed. The scanning system includes at least one laser scanning module having a laser emitter for emitting a light blade to illuminate the upper portion of the tube or profile to be processed. The scanning system also includes a camera for acquiring an image of the portion of the tube or profile illuminated by the light blade. The processing head is mounted to be translatable in a lateral direction, i.e., in a direction located in a plane perpendicular to the longitudinal axis of the tube or profile, and preferably also in a vertical direction. The laser scanning module is mounted to be drivably connected to the processing head, at least during the lateral translational movement.

[0007] This scanning system utilizes the translational motion of a laser scanning module in the lateral direction and the rotational motion of the pipe or profile being processed about its longitudinal axis to make it possible to reconstruct the geometry of the cross-sectional profile of a pipe or profile of any shape and size.

[0008] In this scanning system, the laser emitter and camera of each laser scanning module are placed at a certain distance from each other, with an angle between the camera's visual axis and the propagation direction of the light blade emitted through the laser emitter. The size of the camera's visual cone depends on the camera and its optical system. The camera's visual cone intersects the plane of the light blade emitted through the laser emitter, thus defining the processing area of ​​the laser scanning module. Since the plane of the light blade is not parallel to the plane of the camera sensor, focusing on the entire processing area is quite complex. In fact, for optimal focusing, an optical system with infinite depth of field, or at least a depth of field equal to the height of the trapezoid formed by the intersection of the plane of the light blade and the camera's visual cone, would be required. Therefore, using this scanning system, the only possible way to increase the depth of field is to close the aperture of the optical system, but this leads to the following two disadvantages:

[0009] If the aperture is closed, the amount of light that can be captured by the optical system is reduced, and therefore, the exposure time must be increased in order to obtain a sufficiently bright image;

[0010] Excessive closure of the aperture can cause excessive light diffraction and reduce image sharpness. Utility Model Content

[0011] The purpose of this invention is to provide a machine for processing pipes and profiles, particularly a machine for laser processing (e.g., laser cutting) of pipes and profiles, the machine being equipped with a scanning system for scanning the profile of the cross-section of the pipe or profile being processed, which overcomes the disadvantages of the prior art discussed above.

[0012] According to this invention, this and other objectives are fully achieved by a machine used for processing pipes and profiles.

[0013] In summary, this invention is based on the idea of ​​using a camera configured in such a way that, for each laser scanning module of the aforementioned type of scanning system, the optical axis of the camera is tilted at an angle relative to the plane perpendicular to the camera sensor (i.e., in this way, the optical plane of the camera lens is tilted at an angle relative to the plane of the camera sensor), and more specifically, towards the plane where the light blade generated by the laser emitter of the respective laser scanning module is located. In this way, image focusing of the processing area is improved due to the Scheimpflug principle.

[0014] Preferably, the angle of inclination of the optical axis of the camera lens relative to the direction perpendicular to the plane of the camera sensor is selected so that the focal plane of the camera lens coincides with the plane of the light blade generated by the laser emitter of the respective laser scanning module, so that the image of the processing area is focused in the best manner.

[0015] Using a camera configured in this way is clearly a simple and inexpensive solution for improving the focusing of images in the processing area. Such a camera can be specially manufactured to have the desired tilt between the optical axis and the direction perpendicular to the sensor plane, or it can be obtained by modifying an existing camera by inserting an adapter between the camera lens and the camera sensor to achieve the desired tilt between these two components.

[0016] According to an embodiment, the scanning system includes at least one first laser scanning module and at least one second laser scanning module, which are arranged on opposite sides of a vertical plane passing through the machine's supply axis.

[0017] Preferably, the laser scanning module is arranged such that the light blades generated by the laser emitter are located in the same plane, preferably in the aforementioned vertical plane. Attached Figure Description

[0018] Further features and advantages of this utility model will become clear from the following detailed description, which is given by way of non-limiting example only with reference to the accompanying drawings, wherein,

[0019] Figure 1 This is a perspective view according to an embodiment of the present utility model, which partially shows a machine for processing pipes and profiles, specifically a machine for laser cutting pipes and profiles, equipped with a scanning system for scanning the contour of the cross section of the pipe or profile being processed.

[0020] - Figure 2 yes Figure 1 Front view of the machine;

[0021] - Figure 3 yes Figure 1 A side view of the machine;

[0022] - Figure 4 and Figure 5 These are stereoscopic and front views, schematically illustrating the laser scanning module of the scanning system relative to the [other view / other view]. Figure 1 The arrangement of pipes or profiles being processed in the machine;

[0023] - Figure 6 It is shown in detail Figure 1 A view of one of the two laser scanning modules of the machine's scanning system; and

[0024] - Figure 7 yes Figure 6 The diagram illustrates the operating principle of the camera in the laser scanning module. Detailed Implementation

[0025] In the following description and claims, the term "longitudinal" is used to indicate a direction that coincides with or is parallel to the machine's feed axis (or processing axis), while the term "transverse" is used to indicate a direction located in a plane perpendicular to the machine's feed axis.

[0026] First refer to Figure 1 According to this invention, machines used for processing pipes and profiles are generally denoted by M. In the examples presented herein, machine M is a machine for cutting pipes and profiles, particularly laser cutting, but this invention is equally applicable to machines arranged to perform other types of processing on pipes and profiles, such as welding operations. Furthermore, in the following description, reference is made to the application of machines for laser cutting of pipes, but it is clear that it can be used equally for profiles. The machines are capable of processing pipes or profiles with cross-sections of different shapes and sizes, such as round pipes, square pipes, rectangular pipes, C-profiles, T-profiles, IPE profiles, HEA profiles, etc.

[0027] Machine M, in a manner known per se, includes a base 10, a processing head 12 arranged to perform a processing operation (cutting operation in this example) on the tube T by means of a focused laser beam emitted through a laser nozzle 18, a supply device 14 arranged to move the tube T forward along a supply axis (or processing axis) x, the longitudinal axis of the tube T being processed being aligned with the supply axis (or processing axis) x, and a scanning system arranged to scan at least a portion (particularly the upper portion) of the profile of the cross-section of the tube T. In the illustrated embodiment, machine M also includes a guide device 16 positioned upstream of the processing head 12 and arranged to guide the tube T as it moves forward toward the processing head 12 via the supply device 14. However, the guide device 16 may be omitted.

[0028] See also Figures 2 to 5 The scanning system includes at least one laser scanning module 20. Each laser scanning module 20 sequentially includes a laser emitter 22 arranged to emit a light blade L to illuminate a portion of the processed tubular material T, and a camera 24 arranged to acquire an image of the portion of the processed tubular material T illuminated by the light blade L emitted through the laser emitter 22. Preferably, as illustrated herein, the scanning system includes two laser scanning modules 20, configured such that one is on one side of a vertical plane passing through the supply axis x, and the other is on opposite sides of the vertical plane passing through the supply axis x, and is also arranged above the supply axis x (e.g., particularly...). Figure 2 and Figure 5 (As can be seen). However, more than two laser scanning modules can be configured.

[0029] The processing head 12 is movable relative to the base 10 in the transverse plane, i.e., in a plane perpendicular to the supply axis x (vertical plane, assuming the supply axis x is horizontal). Specifically, the processing head 12 is movable in the transverse plane at least in the horizontal direction ( Figure 1 and Figure 2 The direction denoted by y (and also referred to as the horizontal direction in the following text) is movable, preferably in both the horizontal direction y and the vertical direction ( Figure 1 and Figure 2Both (represented by z) are movable. In this respect, for example, the processing head 12 is carried by a head support structure 26, which is mounted on a slider 28 so as to be translatable in the vertical direction z. The slider 28 is also mounted so as to be translatable in the transverse direction y. Thus, the processing head 12 is movable in the transverse plane with two degrees of freedom, namely one degree of translation in the vertical direction z and one degree of translation in the transverse direction y. Furthermore, in the illustrated embodiment, the processing head 12 is preferably (although not necessarily) mounted on the head support structure 26 so as to be tilted about a transversely pointing inclined axis t (or, according to another embodiment not shown, about two mutually perpendicular inclined axes). The processing head 12 can also move in a direction parallel to the supply axis x.

[0030] The supply device 14 is preferably configured to control not only the translational movement of the tube T along the supply axis x (supply movement), but also the rotational movement of the tube T about this axis. In the case of a machine used for laser cutting of tubes, the combination of the degrees of freedom of movement of the processing head 12 (translation along the lateral direction y and translation along the vertical direction z, and possibly rotation about the inclined axis t and / or translation along the direction of the supply axis x) with the degrees of freedom of movement of the tube T (translation along the direction of the supply axis x and rotation about the supply axis x) allows for cuts to be made on the wall of the tube T along any cutting line.

[0031] Two laser scanning modules 20 are mounted on a support structure 30, which is also fixed to a slider 28. Therefore, the laser scanning modules 20 move together with the slider 28, and thus also with the processing head 12, in the lateral direction y. According to another embodiment (not shown), the support structure on which the laser scanning modules are mounted is fixed to a head support structure, or typically to a slide on which the processing head is mounted. In this way, the laser scanning modules are driven to translate in both the lateral direction y and the vertical direction z.

[0032] In the illustrated embodiment, the support structure 30 has an overall C-shaped configuration, comprising a cross member 32 attached to the slider 28 and a pair of longitudinally extending side arms 34 attached to opposite ends of the cross member 32. Each mounting flange 36 securely connects to the free end of the side arm 34. Similarly, each mounting flange 38 is fixedly connected to one end of the support arm 40 of the respective laser scanning module 20 (the support arm 40 preferably extends in alignment with the respective side arm 34, and the laser emitter 22 and camera 24 are mounted on the support arm 40). Therefore, by connecting (e.g., by screws) the mounting flanges 38 of the respective support arm 40 to the mounting flanges 36 of the respective side arm 34, each laser scanning module 20 can be easily mounted on the support structure 30.

[0033] Reference Figure 4 and Figure 5 Each laser emitter 22 is arranged to produce a light blade L with an aperture of a certain angle α (e.g., 20°). Preferably, each laser emitter 22 is provided with an optical system in a manner known to exist, so that light is propagated uniformly throughout the entire aperture of the blade, or at least most of it. Preferably, each laser emitter 22 is mounted such that its optical axis (denoted as o1) is located in a transverse plane. Furthermore, as... Figure 5 As shown, the optical axis o1 of each laser emitter 22 is tilted at a certain angle β relative to the horizontal line. Preferably, the optical axes o1 of the laser emitters 22 of the laser scanning module 20 are located in the same plane. More preferably, when the processing head 12 is arranged so that the optical axis o1 of the laser beam emitted through the laser nozzle 18 is tilted at a certain angle β. L When pointed vertically, the vertical plane containing the optical axis o1 of the laser emitter 22 of the laser scanning module 20 passes through the optical axis o of the laser beam emitted by the laser nozzle 18 of the processing head 12. L In this way, the scanning system precisely scans the profile of the tube T at the cross-section where the laser beam emitted through the laser nozzle 18 of the processing head 12 acts during processing. This clearly ensures the highest possible accuracy.

[0034] Each camera 24 is preferably mounted in such a manner that the optical axis of each camera 24 ( Figure 3 and Figure 4 The laser 24 (denoted as o2) is coplanar with the optical axis o1 of the laser emitter 22 of the same laser scanning module 20 and tilted toward the optical axis o1 of the laser emitter 22 of the same laser scanning module 20, so as to allow the acquisition of an image of a portion of the surface of the processed tube T illuminated by the light blade L emitted by the laser emitter 22. The camera 24 is connected to a processing unit (also not shown, and of a known type) by means of a suitable data transmission line (not shown, but any type known), which is arranged to process the images acquired by each camera to reconstruct the geometry of the entire or at least a portion of the cross-section of the processed tube T.

[0035] Now for reference Figure 6 and Figure 7Each camera 24 includes a lens system 42 and a sensor 44 in a manner known to exist, particularly (but not necessarily) a CMOS sensor. The lens system 42, in turn, includes a lens 46 (or more generally, at least one lens) in a manner known to exist. According to the present invention, each camera 24 is configured such that the optical axis o2 of the lens system 42 of the camera 24 is tilted at an angle (denoted as φ) relative to a direction perpendicular to the sensor plane (denoted as SP) of the sensor 44, i.e., such that the lens plane (denoted as LP) of the lens 46 is tilted at an angle φ relative to the sensor plane SP, and more specifically, towards the plane (denoted as WP) where the light blade L generated by the laser emitter 22 of the respective laser scanning module 20 is located. This tilt can be achieved, for example, particularly when using a standard camera, by inserting an adapter 48 between the lens system 42 and the sensor 44. In this way, due to the Schiemfuller principle, the focal plane of the lens system 42 is brought closer to the plane WP of the light blade L, thereby improving the focus of the image of the processed area.

[0036] In particular, such as Figure 7 As shown, the tilt angle φ between the lens system 42 and the sensor 44 of the camera 24 is selected so that the focal plane (denoted as FP) of the lens system 42 coincides with the plane WP of the light blade.

[0037] Therefore, the approach proposed in this paper allows the performance of known scanning systems (in particular those known from the documents referenced in the introductory section of this specification) to be improved in a simple and inexpensive manner, ensuring optimal focus in the processing area.

[0038] In this document, the present invention has been described with reference to one possible embodiment. It will be understood that other embodiments sharing the same inventive core as the embodiment described herein can be foreseen, as defined in the appended claims.

Claims

1. Processing machines for processing pipes and profiles (T), including: Processing head (12) The supply device (14) is designed to move each piece of tubing or profile (T) to be processed forward along the supply axis (x) toward the processing head (12), and A scanning system is used to scan the profile of the cross-section of the pipe or profile (T) being processed. The scanning system is characterized by comprising at least one laser scanning module (20), the laser scanning module (20) having a laser emitter (22) and a camera (24), the laser emitter (22) being arranged to emit a light blade (L) to illuminate at least a portion of the tube or profile (T) being processed, and the camera (24) being arranged to capture an image of the portion of the tube or profile (T) illuminated by the light blade (L), and The camera (24) of the at least one laser scanning module (20) includes a lens system (42) and a sensor (44). The camera (24) is configured such that the optical axis (o2) of the lens system (42) is tilted at an angle (φ) relative to the direction (s) of the sensor plane (SP) perpendicular to the sensor (44) toward the light blade (L) generated by the laser emitter (22) of the at least one laser scanning module (20).

2. The processing machine according to claim 1, characterized in that, The angle (φ) between the sensor (44) of the camera (24) and the lens system (42) is such that the focal plane (FP) of the lens system (42) coincides with the plane (WP) of the light blade (L) generated by the laser emitter (22).

3. The processing machine according to claim 1 or claim 2, characterized in that, The camera (24) of the at least one laser scanning module (20) includes an adapter (48) that is inserted between the lens system (42) and the sensor (44) to tilt the lens system (42) relative to the sensor (44) at the tilted angle (φ).

4. The processing machine according to claim 1 or claim 2, characterized in that, The processing head (12) is mounted so that it can be translated in a horizontal direction relative to the pipe or profile (T) being processed, i.e., in a direction perpendicular to the supply axis (x), and the at least one laser scanning module (20) is connected to the processing head (12) so that it becomes part of the processing head (12) during the translational movement in the horizontal direction.

5. The processing machine according to claim 4, characterized in that, The processing head (12) is mounted so that it can be translated vertically relative to the pipe or profile (T) being processed.

6. The processing machine according to claim 5, characterized in that, The at least one laser scanning module (20) is connected to the processing head (12) so that it becomes an integral part of the processing head (12) during translational movement in the vertical direction.

7. The processing machine according to claim 1 or claim 2, characterized in that, The scanning system includes at least one first laser scanning module (20) and at least one second laser scanning module (20), which are arranged on opposite sides of a vertical plane passing through the supply axis (x).

8. The processing machine according to claim 1 or claim 2, characterized in that, The laser scanning module (20) is arranged such that the light blades (L) generated by their respective laser emitters (22) are located in the same plane (WP).

9. The processing machine according to claim 8, characterized in that, The same plane (WP) is a horizontal and vertical plane, that is, a plane perpendicular to the supply axis (x).

10. The processing machine according to claim 1 or claim 2, characterized in that, The processing head (12) is configured to emit a focused laser beam to perform processing operations on the tube or profile (T).

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