Method for automatically adjusting the straightening of metal elements of elongated shape and apparatus for straightening the same elements

Abstract

The method for automatically adjusting the straightening of metal elements of elongated shape, in particular iron rods, provides to prearrange a drawing and/or straightening assembly (3) for straightening and feeding at least one metal element (2) of elongated shape along a feeding direction (A) on a work plane (5), at least theoretical, and a control assembly, predisposed to send to said drawing and/or straightening assembly (3) adjustment commands for the straightening parameters. Moreover, the method provides to prearrange a detection assembly (10) comprising at least a first detection member (11) arranged on a first detection plane (21), a second detection member (12) arranged on a second detection plane (22), predisposed to detect at least a first datum and a second datum respectively, each indicating the instantaneous value of a respective distance from a cross-section of the metal element (2) of elongated shape in the moment when it crosses the first detection plane (21) and the second detection plane (22) respectively, and an acquisition and processing device of said first datum and second datum.

Claims

1. A method for automatically straightening of metal elements of elongated shape, the method comprising the steps of: (a) prearranging a drawing and/or straightening assembly to straighten and feed at least one of the metal elements of elongated shape along a feeding direction, a work surface downstream of said drawing and/or straightening assembly, on which said at least one metal element is configured to be fed along said feeding direction and a control assembly configured to send adjustment commands for straightening parameters to said drawing and/or straightening assembly; (b) prearranging a detection assembly comprising at least one first detection member configured to detect within at least one first detection plane transverse to said feeding direction, downstream, according to said feeding direction, of said drawing and/or straightening assembly, said detection assembly further comprising at least one second detection member configured to detect within at least one second detection plane transverse to said feeding direction, said at least one second detection plane being arranged in succession to said at least one first detection plane with respect to said feeding direction, said work surface being interposed between at least one of said at least one first detection member and said at least one second detection member and said at least one metal element when being fed along said feeding direction, at least one of said at least one first detection member and said at least one second detection member being protected by said work surface and said at least one metal element being freely mobile starting from said work surface at one or more of said at least one first detection plane and said at least one second detection plane, said at least one first detection member being configured to detect at least one first datum and said at least one second detection member being configured to detect at least one second datum, each of said at least one first datum and said at least one second datum indicating an instantaneous measurement of a respective distance from a cross-section of said at least one metal element of elongated shape in a moment when said at least one metal element passes respectively through said at least one first detection plane and said at least one second detection plane, said detection assembly further comprising an acquisition and processing device for said at least one first datum and said at least one second datum; (c) feeding said at least one metal element of elongated shape along said feeding direction; (d) detecting said at least one first datum by said at least one first detection member when said at least one metal element of elongated shape passes through said at least one first detection plane with a respective cross-section; (e) sending said at least one first datum to said acquisition and processing device; (f) detecting said at least one second datum by said at least one second detection member when said at least one metal element of elongated shape passes through said at least one second detection plane with said respective cross-section; (g) sending said at least one second datum to said acquisition and processing device; (h) processing said at least one first datum and said at least one second datum via said acquisition and processing device for estimating an instantaneous geometric configuration assumed by said at least one metal element in a space defined between said at least one first detection plane and said at least one second detection plane and for detecting a possible anomaly with respect to a desired geometric configuration of said at least one metal element; (I) sending, by said acquisition and processing device to said control assembly at least one of said at least one first datum and said at least one second datum relative to said estimated configuration and said detected anomaly, so that said control assembly transmits corresponding straightening adjustments commands to said drawing and/or straightening assembly.

2. A method according to claim 1, wherein at least one of said at least one first detection member and said at least one second detection member is a proximity sensor, the proximity sensor being a type of magnetoresistive sensor.

3. A method according to claim 2, wherein said steps from (d) to (I) are carried out in continuous manner for a continuous adjustment of straightening of said at least one metal element of elongated shape.

4. A method according to claim 3, further comprising a step of sending at least one further first datum detected by said at least one first detection member in a moment intermediate between detection of said at least one first datum and said at least one second datum to said acquisition and processing device, wherein said step (h) of processing by said acquisition and processing device said at least one first datum and said at least one second datum comprises a further step of comparing said at least one first datum, said at least one second datum and said at least one further first datum, to estimate said instantaneous geometric configuration assumed by said at least one metal element in said space defined between said at least one first detection plane and said at least one second detection plane.

5. A method according to claim 2, wherein said respective cross-section is an end front portion of said at least one metal element of elongated shape, detected by said at least one first detection member and subsequently by said at least one second detection member.

6. A method according to claim 2, wherein said step (d) of detecting said at least one first datum and said step (f) of detecting said at least one second datum occur in a same instant on respective spaced cross-sections of said at least one metal element being fed.

7. A method according to claim 1, wherein the at least one metal element is a rod.

8. An apparatus for automatically straightening metal elements of elongated shape, the apparatus comprising: a drawing and/or straightening assembly configured to feed and straighten at least one metal element of elongated shape along a feeding direction; a work surface downstream of said drawing and/or straightening assembly, on which said at least one metal element is configured to be fed along said feeding direction; a control assembly configured to send instruction for straightening parameters to said drawing and/or straightening assembly; a detection assembly comprising at least one first detection member configured to detect within at least one first detection plane transverse to said feeding direction, downstream, according to said feeding direction, of said drawing and/or straightening assembly, the detection assembly further comprising at least one second detection member configured to detect within at least one second detection plane transverse to said feeding direction, said at least one second detection plane being arranged in succession to said at least one first detection plane with respect to said feeding direction, said work surface being interposed between at least one of said at least one first detection member and said at least one second detection member, said at least one metal element being fed along said feeding direction, at least one of said at least one first detection member and said at least one second detection member being protected by said work surface and said at least one metal element being freely mobile starting from said work surface at one or more of said at least one first detection plane and said at least one second detection plane, said at least one first detection member being further configured to detect at least one first datum and said at least one second detection member being configured to detect at least one second datum, each of said at least one first datum and said at least one second datum indicating an instantaneous measurement of a respective distance from a portion of said at least one metal element of elongated shape in a moment when said at least one metal element passes respectively through said at least one first detection plane and said at least one second detection plane, said detection assembly further comprising an acquisition and processing device of said at least one first datum and said at least one second datum for processing the instantaneous configuration assumed by said at least one metal element of elongated shape in the space defined between said at least one first detection plane and said at least one second detection plane along said feeding direction and for sending possible straightening adjustment commands to said control assembly, in case said instantaneous processed configuration varies from a desired configuration.

9. An apparatus according to claim 8, wherein at least one of said at least one first detection member and said at least one second detection member is a proximity sensor, said proximity sensor being a type of magnetoresistive sensor.

10. An apparatus according to claim 9, wherein said detection assembly works continuously, said at least one first detection member and said at least one second detection member being configured to continuously detect said at least one first datum and said at least one second datum and at least one of a further first datum and a further second datum, for respective portions of said at least one metal element progressively being fed, and to send said at least one first datum and said at least one second datum and said at least one of said further first datum and said further second datum to said acquisition and processing device.

11. An apparatus according to claim 10, wherein at least one of said at least one first detection member is oriented on said at least one first detection plane and said at least one second detection member is oriented on said at least one second detection plane so as to be able to detect said distance, substantially perpendicular to said feeding direction.

12. An apparatus according to claim 9, further comprising at least one further detection member between said at least one first detection member and said at least one second detection member and is protected by said work surface, said at least one metal element being freely mobile starting from said work surface at said respective detection plane.

13. An apparatus according to claim 12, wherein said at least one further detection member is a proximity sensor, the proximity sensor being a type of magnetoresistive type.

14. An apparatus according to claim 9, further comprising at least one of a guide and a cut assembly downstream of said drawing and/or straightening assembly, said at least one first detection member and said at least one second detection member being disposed downstream of said guide and/or cut assembly, with respect to said feeding direction, so as to be able to detect the position of portions of said at least one metal element to be straightened, in a space in which said at least one metal element is maximally free to arrange itself on the work surface.

15. An apparatus according to claim 8, further comprising at least one further detection member arranged within at least one of said at least one first detection plane and said at least one second detection plane, said at least one further detection member being configured to detect a further datum indicating a respective further distance of said portion of said at least one metal element being fed, and to send said further datum to said acquisition and processing device, said acquisition and processing device being configured to calculate an exact position of said cross-section passing therethrough, calculated with respect to at least one of said at least one first detection plane and said at least one second detection plane by processing at least one of said at least one first datum and said further datum.

16. An apparatus according to claim 15, wherein said at least one further detection member is between said at least one first detection member and said at least one second detection member and is optical.

17. An apparatus according to claim 15, wherein said at one further detection member between said at least one first detection member and said at least one second detection member is a laser.

18. An apparatus according to claim 8, wherein said at least one of said at least one first detection member and said at least one second detection member comprises a magnetic field source arranged within at least one of said at least one first detection plane and said at least one second detection plane, a first sensible magnetoresistive element configured to emit a first output signal and a second sensible magnetoresistive element configured to emit a second output signal, said first sensible element and said second sensible element being electrically disjointed, said first output signal and said second output signal being indicative of a distortion of a magnetic field generated by said magnetic source at the passage of one said portion of said at least one metal element through at least one of said at least one first detection plane and said at least one second detection plane, each of said at least one first detection member and said at least one second detection member being associated with said acquisition and processing means, configured to process said first signal and said second signal, and to determine, as a result, a value of a first coordinate and a value of a second coordinate on at least one of said at least one first detection plane and said at least one second detection plane, defining uniquely an instant position of a barycenter of a passage portion on said respective detection plane.

19. An apparatus according to claim 8, wherein said at least one metal element is an iron rod.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The details of the invention will become more apparent from the detailed description of a preferred embodiment of the apparatus for straightening metal elements, of elongated shape predisposed to carry out the method for automatically adjusting the straightening of the same elements, illustrated for indicative purposes in the attached drawings, wherein:

(2) FIG. 1 shown a front view of the apparatus according to the invention;

(3) FIG. 2 shows a detail of the apparatus shown in FIG. 1;

(4) FIGS. 3a, 3b and 3c show a cross-sectional view of the apparatus, in subsequent working steps.

BEST MODE

(5) With particular reference to FIGS. 1 to 3c, the apparatus for straightening metal elements 2 of elongated shape is indicated in its entirety with 1.

(6) The apparatus 1 comprises a drawing and/or straightening assembly 3 of known type, a guide unit 4 at the edge of which a cut assembly is usually housed, arranged in succession along a feeding direction A of the metal element 2 or rod on a work plane 5. The apparatus possibly comprises also a bending unit arranged downstream of the guide unit 4 in a suitable seat 6 on the work plane 5.

(7) Downstream of the guide unit 4 or in a space in which the rod 2 is free to arrange along the work plane 5, there is a detection assembly 10.

(8) The apparatus comprises as well a control unit, predisposed to send the drawing and/or straightening assembly 3 adjustment instructions of the straightening parameters.

(9) The detection assembly 10 comprises at least a first detection member 11 that reads on a first detection plane 21 transverse to the feeding direction A, downstream, according to the feeding direction A, of the drawing and/or straightening assembly 3, a second detection member 12 that reads on a second detection plane 22 transverse to the same feeding direction A, in succession to the first detection plane 21 with respect to the feeding direction A.

(10) The first detection member 11 and the second detection member 12 are predisposed to detect at least one first datum and a second datum respectively, each indicating the instantaneous value of a respective distance from a cross-section of the rod 2 in the moment when it crosses the first detection plane 21 and the second detection plane 22 respectively.

(11) The detection assembly 10 further comprises an acquisition and processing device of the first datum and second datum, outputting from the first detection member 11 and the second detection member 12, to calculate the instantaneous configuration of the rod 2 being fed along the feeding direction A.

(12) The first detection member 11 and the second detection member 12 are arranged preferably below the work plane 5, protected by this latter (see FIG. 2, in which the first detection member 11 and the second detection member 12 are represented by the dotted line).

(13) The first detection member 11 and the second detection member 12 are preferably proximity sensors of magnetoresistive type, of the type disclosed in patent application PCT/IB2015/058185 in the name of the Applicant and corresponding WO publication, WO 2016/063256 A1, the entire contents of each application are incorporated herein by reference.

(14) In particular, such detection member, comprising a couple of magnetoresistive elements electrically disjointed, influenced by a same magnetic field source, allows to detect, on the respective detection plane, respective distortions of the resulting magnetic field, due to the passage of the metal element 2. The detection member 11, 12 then outputs a couple of coordinates, which indicate the exact position on the same detection plane of the cross-section of the metal element 2 passing therethrough.

(15) Thus, the said specific detection members do not need to “see” the metal element 2, thus to be placed on the same side of the element with respect to the work plane 5, to read in precise and reliable way the instantaneous position of the element 2, useful for obtaining its instantaneous configuration and, therefore, any straightening anomalies.

(16) Conversely, such detection members 11, 12 detect the passage of the metal element 2, even though they are protected by the work plane 5. In this way, they do not in any way interfere with the substantially free arrangement of the metal element 2 on the work plane 5, and with the necessary work space, especially if the element 2 is subjected to bending operations on the same work plane 5. In fact, in such case, the metal element 2 requires, around the bending assembly on the work plane 5, a large space free of hindrance, in which the different successively bent portions of the element 2 can rotate.

(17) The acquisition and processing device can then send the control unit possibly detected data or signals indicating detected anomalies, if the calculated instantaneous configuration differs from a desired rectilinear configuration, so that the control unit can send corresponding adjustment commands to the drawing and/or straightening assembly 3.

(18) The functioning of the apparatus for straightening elements of elongated shape according to the invention can be understood from the preceding description.

(19) The first detection member 11 and the second detection member 12 are arranged in succession, with respect to the feeding direction A of the rod 2 at the first detection plane 21 and the second detection plane 22, respectively.

(20) Such detection members are predisposed to detect, that is measure, the value of their distances from the cross-section of the rod 2 that cross the respective detection planes, so as to be able to estimate, thanks to the acquisition and processing device, the size and orientation of a possible anomaly of the configuration taken by the rod 2, with respect to the straightening axis represented by the feeding direction A.

(21) The rod 2 is fed through the drawing and/or straightening assembly 3, being unwound from the respective coil, according to the feeding direction A.

(22) The first detection member 11, being closer to the drawing and/or straightening assembly 3 of the second detection member 12, is the first to detect data.

(23) When the front end of the rod 2 reaches the first detection plane 21, the first detection member 11 detects the first datum, that is, the measurement of the distance between the first detection member 11 and the said front cross-section itself, and sends it to the acquisition and/or processing assembly (see FIG. 3a).

(24) Following the continuous feeding of the rod 2 along the feeding direction A, the front end of the rod 2 reaches the second detection plane 22, where the relative distance is measured by the second detection member 12, that is, the second datum that is sent to the acquisition and processing device.

(25) Preferably, the adjustment unit works continuously, thus the first detection member, in particular, keeps on sending data, that is, distance measurements, to the acquisition and processing device. In the case shown in the FIGS. 3a to 3c, this allows the device to compare the subsequent movements of the detected cross-section, that, in the shown case, moves from a condition adjoined or approached to the work plane 5, to a condition raised from the plane itself.

(26) Thanks to the acquisition of such instantaneous data, coming both from the first detection member 11 and the second detection member 12, the acquisition and processing device can identify in precise way the configuration taken by the rod 2 in the work space between the first detection plane and the second detection plane.

(27) The method according to the invention, carried out by the described apparatus 1, is capable to detect any type of anomaly presented by the rod 2 in straightening step despite the presence of the work plane 5, usually arranged vertically or inclined with respect to a vertical plane. This is, for example, the case of apparatuses for making stirrups.

(28) As a matter of facts, in case the rod 2 tends to curve into one direction, in the space defined between the two indicated detection planes, that is, upwards, downwards or outwards, with respect to the work plane 5, the second detection member confirms the data detected by the first detection member and the acquisition and processing device can identify the size of the detected anomaly.

(29) Conversely, in case the inner tensions of the rod 2 tend to bend it toward the work plane 5, and this constitutes an impediment to such free inflection, then the rod 2 arranges itself according to a profile which has at least one inflection, curving on the same work plane 5 (see especially FIG. 3c).

(30) In fact, if the rod 2 tends to go towards the work plane 5, the first detection member 11 first reads that the end cross-section of the rod 2 is close to the work plane 5 as if the configuration thereof was perfectly straight.

(31) Subsequently, the rod 2 advances by means of the drawing and/or straightening assembly 3 and, being subjected to stress pushing it against the work plane 5, it abuts against the work plane 5, crawling over it and arranging according to an arched profile on the work plane 5. Meanwhile, the first detection member 11 can detect that the cross-sections passing through the first detection plane 21, instant by instant, move away and then gradually approach to the work plane 5 (see FIG. 3a).

(32) When the end of the rod 2 reaches the second detection member 12, this latter detects a position close to the work plane 5. From the combination of the sequence of these data, the acquisition and processing device can identify the anomaly shown by the rod 2 and indicate the value and type of correction to be made to the drawing and/or straightening assembly 3 (see FIG. 3b).

(33) In other words, the data detected by the first detection member 11 are compared to those from the second detection member 12, which advantageously detects its data at a distance from the first detection plane 21, wherein the rod 2 can extend its own shape, fully showing possible anomalies.

(34) For example, it is possible to highlight bigger bends present in the rod 2, through the apparatus according to the invention, by appropriately modulating the distance along the feeding direction A between the first detection plane 21 and the second detection plane 22.

(35) In practice, the used materials as well as the size and shape may vary according to the needs.

(36) Should the technical characteristics mentioned in the claims be followed by reference signs, such reference signs were included for the sole purpose of increasing the understanding of the claims and thus they shall not be deemed limiting the scope of the element identified by such reference signs by way of example.