APPARATUS FOR CURVING OBLONG, IN PARTICULAR METALLIC, ELEMENTS

Technical field

[01] The present invention relates to an apparatus for curving oblong, in particular metallic, elements, for example bars, in particular iron rods for reinforced concrete, possibly obtained as well by cutting from bars or rolls.

Background of the invention

[02] Apparatuses for bending oblong, in particular metallic, elements, such as metal section bars and the like produced in bars, are known in the art.

[03] The known type of bending apparatuses includes operating parts, such as a central contrasting roller, cooperating with a pair of curving rollers, whose mutual distance is adjustable, on a work surface orthogonal to the axis of the rollers themselves, to achieve the desired curvature. At least one of these curving members can be motorized, so as to drag the feeding elements.

[04] A passage channel for the oblong element to be bent is therefore defined between the contrast roller and the pair of curving rollers. Once said distance has been set, between the curving rollers and the contrast roller, the element is fed through the passage channel, where the engagement carried out by said rollers achieves the desired curvature.

[05] Unlike bending apparatuses, the purpose of such apparatuses is to bend each element with a radius of curvature greater than that of the central contrast roller, for example with a given medium or large radius, for example of width ranging from a few tens of centimeters to several tens of meters.

[06] The curvature to be carried out can concern the entire length, sometimes tens of meters, of the oblong element or only a part thereof, or can be variable in a specific way in the length.

[07] Consequently, the equipment involved, especially to ensure the correct support of the pieces during processing, is rather cumbersome.

[08] It is also difficult to guarantee the desired precision for the curvature, given the extension of the pieces involved. In fact, even a slight error in the machining setting and/or an irregularity in the element can compromise the machining of the piece.

[09] Therefore, the known solutions are not able to meet the needs of the specific sector, for the dimensions, for the cost of the necessary equipment, and for the risk of machining waste due to insufficient precision.

Disclosure

[10] The aim of the present invention is to solve the problems mentioned in the prior art, by devising an apparatus for curving oblong, in particular metal elements, that allows these elements to be curved automatically and in a repeatable manner.

[11] As a part of this aim, it is a further object of the present invention to provide a curvature detection assembly that achieves the aforementioned purpose with a simple and functional structure, provided with reliable operation and great flexibility of use.

[12] The aforementioned objects are achieved, according to the invention, by the apparatus for curving oblong elements according to claim 1 and by the curvature detection assembly according to claim 7.

[13] The apparatus for curving oblong, in particular metallic elements, comprises a curvature assembly, comprising in turn a contrast member around which an element can be curved with a certain radius of curvature, so as to be arranged downstream of the curvature assembly according to a curved development.

[14] Curved development is defined as a development that differs from a rectilinear or substantially rectilinear development, which can therefore be characterized by a numerically determined, not indefinite, radius of curvature.

[15] The apparatus comprises a curvature detection assembly disposed downstream of the curvature assembly, defining a curvature plane for receiving the fed element along a direction of travel through the curvature assembly.

[16] The detection assembly comprises a detection device comprising at least one sensitive element arranged on the curvature plane, to detect, in the presence of the element on the curvature plane, a data indicative of the curved development of the element fed along the direction of travel.

[17] The apparatus also comprises processing means associated with the detection device to process the detected data so as to obtain the curvature of the curved development, actually imprinted by the curvature assembly on the element.

[18] The curvature detection assembly can be mounted in a fixed or movable manner, in particular it can be oscillable and/or translatable, with respect to the curvature assembly.

[19] Preferably, the sensitive element defines a detection zone that extends in a rectilinear or curved manner, transversely to the direction of travel and/or curved development assumed by the element.

[20] According to a particular aspect, the curvature detection assembly may be mounted in a fixed, aligned or inclined manner with respect to the direction of travel.

[21] According to a particular aspect, the curvature detection assembly may be oscillably mounted about an axis of oscillation transverse, in particular orthogonal, to the plane of curvature.

[22] The detection device preferably comprises at least three sensitive elements, arranged in succession on the plane of curvature with respect to the direction of travel.

[23] According to an aspect of the invention, possibly autonomous, the curvature detection assembly for oblong, in particular metal, elements is arranged downstream, with respect to a direction of travel, of a curvature assembly comprising, for example, a contrast member, around which an element can be curved on a plane of curvature with a certain radius of curvature, greater than the radius of a contrasting operative portion of the same contrast member.

[24] The contrast member can be made up, for example, of a contrast roller.

[25] In the event that the contrast member is made up of a roller, the latter radius coincides with the radius of the contrast roller. However, in the case of a contrasting member of different shape, the latter radius is the radius of curvature of a shaped operative portion, in which the abutment with the element occurs during the curvature.

[26] In particular, the bending assembly may comprise several contrast rollers, or operative members of a different type with respect to the contrast roller, such as a track, as long as they are adapted for the purpose of curving the elements.

[27] The contrast member may be rotatable, idle or actuated, around a respective axis, orthogonal to the plane of curvature.

[28] The sensing assembly can be physically separated as a stand-alone bench or integrated into the curving assembly.

[29] The curvature detection assembly defines the aforementioned curvature plane for receiving the element being fed through the curvature assembly.

[30] Preferably, the detection assembly also performs a function of supporting the elements being machined.

[31] The curvature detection assembly comprises at least one detection device arranged downstream of the curvature assembly on the curvature plane, to detect, as the element passes over the curvature plane, a datum indicative of the trajectory actually followed by the element being fed, and processing means associated with the detection device for processing the detected data, so as to verify the effect of the curving action performed by the curving assembly on the element.

[32] In essence, according to the invention it is possible to verify the accuracy and effectiveness of the curvature action carried out by the curvature assembly, thanks to a continuous "in line" monitoring carried out by the detection device on the trajectory of the elements being processed. This monitoring in turn makes it possible to continuously adjust the operating parts even during processing.

[33] Advantageously, the detection device can detect the aforementioned trajectory in a section in which the element is free from any constraint that is imposed by operative members, in particular by the curvature members. On the contrary, in the constraint areas in which the operative members operate, the element tends to follow an "induced" trajectory, distorted by the generation of internal tensions.

[34] The detection device of the detection assembly comprises at least one sensor element, preferably a plurality of sensor elements. [35] The sensor element defines a detection zone that preferably develops transversely to the direction of travel of the element, so as to effectively verify the trajectory actually followed during the curving step or any deviation, in particular radial, therefrom. In particular, it is thus possible to monitor any deviations from the radius of curvature set for the trajectory, therefore for the curved development of the element.

[36] Preferably, the detection device comprises at least three sensor elements, to correctly detect the trajectory of the curved element, whatever the radius of curvature set for the trajectory.

[37] Preferably the curvature detection assembly comprises a plurality of sensitive elements arranged in succession on the curvature plane, with respect to the direction of travel of the element through the curvature assembly.

[38] The curvature detection assembly can be fixed or movable.

[39] In particular, if the detection assembly is fixed, it may be arranged aligned with the curving assembly along the direction of travel of the elements, or inclined with respect thereto.

[40] At least one sensitive element of the detection device preferably has the detection zone extending transversely to the feed direction, so as to be able to detect in any case the element being processed downstream of the curvature assembly. It should be noted that the trajectory of the element is even more spaced from the direction of travel and therefore from a hypothetical straight development coinciding therewith as the radius of curvature imposed by the curvature members is smaller.

[41 ] In particular, but not only, in case the detection assembly is fixed, the first sensitive element, closest to the curvature assembly, can be advantageously arranged about 30 cm off the area in which the curvature members release the oblong element being processed, and can have a detection area that extends transversely for at least 4 cm.

[42] The detection zone of the sensitive element may advantageously be related to a range of curvature radiuses to be detected.

[43] For this purpose, the sensor elements can extend considerably in a direction transverse to the aforementioned direction of travel.

[44] The detection area of the at least one sensitive element can extend in straight or curved manner.

[45] In the case of a plurality, the sensitive elements can have a different conformation, in particular be shaped as segments or arcs of circumference, extension and/or radius of curvature, even different from each other.

[46] The detection assembly is preferably orientable, being hinged around an axis of oscillation orthogonal to the plane of curvature. The oscillation around the axis of oscillation permits to adjust the positioning of the same curvature detection assembly as a function of the curving action set for the curvature assembly, therefore of the set radius of curvature, so that the detection device is correspondingly oriented to intercept the element being processed and detect the data of the element being fed.

[47] Advantageously, the curvature detection assembly is preferably orientable around the axis of oscillation according to a manual or automatic adjustment motion, in order to arrange the detection device substantially centrally with respect to the element to be detected and to facilitate the detection of the element being processed. This adjustment is preferably carried out according to the reading interval and/or the detection sensitivity of the sensor element(s): the proximity to the actual trajectory of the element may be the greater, the lower the sensitivity of the detection device.

[48] The axis of oscillation is preferably positioned at a perimeter edge of the curving assembly, intended to be positioned adjacent to the curving assembly.

[49] In addition, the axis of oscillation can be incorporated into a fixed support strut of the curvature detection assembly.

[50] Advantageously, the axis of oscillation can coincide with the axis around which the contrast member is rotatable, or with an axis at the point of tangency between the contrast member and the element being processed.

[51] The curvature detection assembly itself can be cantilevered or supported by further struts abutting on rolling means, to facilitate the aforementioned adjustment motion.

[52] The orientation of the curvature detection unit can be carried out manually or automatically, depending on the set radius of curvature, or on the data detected by the curvature detection device, for example to maintain the centering of the sensors with respect to the trajectory to be detected, even when the actual radius of curvature of the element varies.

[53] The detection device is preferably a magnetoresistive device of the type described in patents EP3209973 and EP3445509, on behalf of the same applicant. Alternatively, the detection device is for example of an optical type, in particular made up of a camera. In the latter case at least certain sensitive elements of the sensing device may be diverged from the curvature sensing assembly.

[54] According to a prerogative of the invention, the curvature detection assembly can read the curvature of the element being processed, however it is oriented, as the element being processed is intercepted by the detection device. Advantageously, the detection of the curvature of the element being processed is carried out in an area where the element is not constrained, but free.

[55] In particular, in the case of a plurality of sensitive elements, the detection is preferably carried out in a section comprised between the first sensitive element and the last of at least three elements, arranged in succession. The curvature detection assembly can read the curvature of the element being machined, however it is oriented, thanks to the geometric principle according to which only one circumference passes through three non-aligned points. Therefore, once three pass points of the curved element have been detected by three sensing elements in succession, the relative radius of curvature is univocally identified.

[56] The detection device enables such detection as the curved element can advantageously fall within the detection range of the provided sensitive elements.

[57] The curvature detection assembly may have any extension, in particular it may extend from the curvature assembly along a longitudinal axis, in a rectilinear manner or in a different manner.

[58] Support groups or benches can be provided downstream of the detection assembly, for example manually or automatically movable, to support the workpieces throughout their extension.

[59] The curvature detection assembly connected to the processing means can therefore indicate the actual radius of curvature of the workpiece and/or directly perform a feedback on the curvature elements in order to correct and/or maintain the predetermined curvature.

[60] The detection assembly can be associated with an orientation device, of the type described in patent application W02020/021582, to permanently maintain the radius of curvature set in a constant manner also for the entire longitudinal extension of the element being processed.

[61] The detection assembly and the apparatus according to the invention enable the reading of the radius of curvature of the element both when it is in feeding motion and when it is stopped.

Description of drawings

[62] The details of the invention will become more apparent from the detailed description of a preferred embodiment of the apparatus for curving oblong, in particular metallic, elements, such as bars, for example iron rods for reinforced concrete, illustrated by way of example in the accompanying drawings, wherein:

Figures 1 and 2 are respectively a perspective view and a plan view of an apparatus implementing the curvature detection assembly according to the invention;

Figures 3 and 4 are respectively a perspective view and a plan view of the same apparatus, in a different operative step;

Figures 5 and 6 are respectively a plan view of a detection assembly according to further embodiments.

Description of embodiments of the invention

[63] With particular reference to these figures, an apparatus for curving oblong elements 2, in particular but not exclusively for bars, such as iron rods for reinforced concrete, is indicated in the whole with the reference numeral 1.

[64] The apparatus 1 comprises a curvature assembly 3 and a curving detection assembly 10 according to the invention, for example but not exclusively made in the form of a detection bench. Curvature means, in particular, a process that in the specific sector is called "calendering".

[65] In a known way, the apparatus 1 comprises feeding means for feeding the element 2 onto a respective work surface 1 a along a direction of travel A (see Figures 1 and 2) through the curvature assembly 3, so that the element 2 undergoes a curvature with a certain radius of curvature (see Figures 3 and 4).

[66] The direction of travel A substantially represents the direction along which the element 2 being processed is inserted between the curvature operative members or is tangent thereto. Therefore, for an initial section upstream of the curvature assembly 3 the direction of travel A can coincide with the longitudinal axis of the element 2 being fed, which is still rectilineal. Downstream of the curvature assembly 3, the element 2 is curved and therefore deflected with respect to the direction of travel A. Basically, the element 2 assumes a curved development downstream of the curvature assembly 3, different from a rectilinear development, which may instead coincide with the feeding direction A.

[67] The curvature assembly 3 can comprise, for example, a contrast member, in particular a contrast roller 31, and at least one curvature element 32, in particular a wheel, opposed, with respect to the direction of travel A, to the contrast roller 31. The curvature wheel 32 is arranged staggered, forwardly or backwardly, in the direction of travel A, with respect to a median plane orthogonal to the same direction of travel A, containing the axis of the roller 31. The bending wheel 32 is also movable along a direction transverse to the direction of travel A to move it closer or further away from the contrast roller 31 and thereby to adjust the curvature to be imparted to the element 2.

[68] Between the contrast roller 31 and the bending wheel 32 a passage channel is defined along which the element 2 is intended to be engaged to assume the desired curvature.

[69] Preferably, the curving assembly 3 comprises a second contrast wheel 33, arranged upstream of the curving wheel 32, on the same side with respect to the direction of travel A.

[70] The curving assembly 3 can optionally also comprise a further member, a guide pin 34, movable along an adjustment stroke transversal to the feed direction A, to act as a guide during the curving step. The guide pin 34 is arranged downstream of the contrast roller 31 with respect to the feed direction A.

[71] The curvature detection assembly 10, which defines a curvature plane 10a, comprises at least one detection device 11 to detect the curvature of the element 2 being processed.

[72] In practice, the detection device 11 performs the function of reading the trajectory or curved development of the element 2 while following the trajectory imposed by the curvature assembly 3 along the curvature plane 10a. [73] The detection device 11 comprises at least one sensitive element 11a to detect the exact position of the element 2 passing on the curvature plane 10a. The element 2 can be stationary or in motion during reading.

[74] The sensor element 11a defines a detection area that develops preferably transversely to the direction of travel A of the element 2, so as to effectively check the trajectory actually followed in the curving step or any deviation, in particular radial, therefrom. In particular, it is thus possible to monitor any deviations from the set radius of curvature.

[75] The transverse extension of the detection zone of the sensitive element 11a can be advantageously correlated to an interval of radiuses of curvature to be detected. In practice, the greater the range, the greater it can be.

[76] The detection device 11 preferably comprises a plurality of sensitive elements 11a, in particular at least three, arranged in succession with respect to the direction of travel A and/or, in particular, to the trajectory followed by the element 2 being processed.

[77] In particular, the provision of at least three sensitive elements 11a can allow the detection device 11 to detect the curvature of the element 2 regardless of the orientation of the detection assembly itself.

[78] Each sensitive element 11a can be made up of sensors of any type, for example of the magnetoresistive type, of means for image detection, of the optical type, such as for example a video camera, LED, laser, or the like or a combination thereof. For example, the sensitive element can be of the type described in patent EP3209973.

[79] The assembly also includes processing means to process the data detected, continuously or discontinuously, by the detection device 11 , to calculate the trajectory, hence the curvature, of the element 2 being processed.

[80] The curvature detection assembly 10 preferably comprises sliding rollers 12, arranged on the curvature plane 10a, to facilitate the feeding of the element 2 being processed. Preferably at least one sliding roller 12 is approached to a respective sensitive element 11a of the detection device 11 , to facilitate the detection of the actual curvature. Each guide roller 12 is arranged with its own axis parallel to the curvature plane 10a and perpendicular to the longitudinal extension of the detection assembly 10.

[81] The curvature detection assembly 10 can be advantageously orientable, to adapt its orientation to the curved trajectory of the element 2 being processed and in particular to allow the element 2 being processed to fall within the detection range of the sensitive element(s) 11a. In particular, in the case of three sensitive elements 11a, the well-known theorem is used according to which one and only one circumference passes through three non-aligned points and therefore it is possible to carry out the desired detection.

[82] More precisely, the curvature detection assembly 10 can be hinged for effective detection, for example near an edge adjacent to the curvature assembly 3, around an oscillation axis 13 orthogonal to the curvature plane 10a.

[83] In particular, the curvature detection assembly 10 is supported by a fixed strut 14, which preferably incorporates said oscillation axis 13.

[84] The curvature detection assembly 10 is supported by further struts 15 preferably abutting on rolling means 16, in order to be able to oscillate between a first configuration, in which the curvature detection assembly 10 is aligned with the work surface 1a of the apparatus 1 along the direction of travel A, and multiple configurations rotated around the axis of oscillation 13, to allow detection of the trajectory of the element 2 being processed. Thanks to this adjustment it is possible to dispose and/or maintain the sensitive elements 11a provided in their reading range, to monitor the actual curvature of the element 2 throughout the processing step.

[85] The operation of the curving apparatus 1 and the curvature detection assembly 10 is understandable from the above description.

[86] In particular, in a first step the curvature assembly 3 is adjusted according to the theoretical radius of curvature to be impressed on the element 2. According to the same radius, the curvature detection assembly 10 can be oriented around the oscillation axis 13 and/or translated along suitable guides, in order to arrange the detection device 11 in such a position as to be able to detect the trajectory provided for the element 2. In particular, the detection assembly 10 can be oriented in such a way that the detection device 11, with the provided number of sensitive elements 11a, can be advantageously arranged in a central way to the set trajectory. Alternatively, as described below, the detection assembly is fixed and the sensitive elements 11a are arranged so as to ensure an effective reading of a determined range of radiuses of curvature.

[87] The feeding of the element 2 is then activated along the direction of travel A, through the bending assembly 3 which therefore carries out, during this feeding, the curvature of the element 2.

[88] The element 2, always being fed, then reaches the curvature plane 10a in a curved configuration and passes through the detection area of the detection device 11.

[89] Continuously or discontinuously, the detection device 11 detects at least one datum indicative of the positioning of the element 2, sending it to the processing means, which can thus calculate and monitor the actual curvature achieved on the element 2.

[90] Advantageously, the processing data can be used to adjust the setting of the operating members of the bending unit 3 and thus correct any deviations from the desired curvature.

[91 ] According to a further embodiment shown in Figure 5, the detection assembly 100 is fixedly mounted, in particular with respect to the operative members of the curvature assembly, for example the contrast roller 31 and the curving wheels 32, 33. According to this embodiment, in particular, the detection assembly 100 is aligned, according to the direction of travel A, to the bending assembly.

[92] In this case, to allow the correct detection of the curvature of the element 2, it is appropriate to arrange the sensitive elements 11a so that the trajectory of the element 2 falls within the respective detection areas.

[93] Advantageously it is possible to provide, in particular in this embodiment, but similarly also in the first embodiment described, that the first sensitive element 11a, the one among the sensitive elements 11a closest to the curvature assembly, is arranged at a longitudinal distance L1 equal to about 30 cm, measured starting from the zone in which the curving members, for example the contrast roller 31 and the first curving wheel 32, release the element 2 and has a transversal extension of the detection zone of at least 4 cm.

[94] This configuration advantageously allows an effective and precise reading of the curvature of the oblong elements 2 being processed, in a very wide range of curvatures. The transverse width of the detection zone of the detection elements can be advantageously proportional to an interval of the curvatures to be detected.

[95] According to a further embodiment shown in Figure 6, quite similar to the embodiment shown in Figure 5, it is possible to provide that the detection assembly 110 is fixedly mounted with respect to the curvature assembly, in particular extending obliquely with respect to the direction of travel A.

[96] Also in this case it is possible to arrange the sensitive elements 11a in succession, so that the respective transverse extension can be substantially centered or in any case within the trajectory of the element 2 being processed. The detection assembly 110 can therefore effectively monitor the result of the curvature carried out by the curvature operative members.

[97] The curving apparatus and the curvature detection assembly for oblong elements according to the invention therefore achieves the purpose of curving of oblong elements in an optimal manner, in particular by ensuring the required precision along the entire extension of the element 2, guaranteeing its repetition and optimizing production efficiency.

[98] In particular, if the sensitive elements are at least three, it is possible to detect, preferably continuously, at any moment, at least three points of the circumference section along which the curvature of the element being processed develops. It is thus possible to determine with optimal precision the radius of curvature of the aforementioned section of the element, even regardless of the orientation assumed by the curvature detection assembly.

[99] In the practical embodiment of the invention, the materials used, as well as the shape and dimensions can vary according to the needs.

[100] Should the technical features mentioned in any claim be followed by reference signs, such reference signs were included strictly with the aim of enhancing the understanding of the claims and hence they shall not be deemed restrictive in any manner whatsoever on the