LU84449A1 - NON-CONTACT DIMENSIONAL MEASUREMENT METHOD OF METAL BEAMS AND APPARATUS FOR IMPLEMENTING SAME - Google Patents

Abstract

1. A non-contact dimensional measuring process for metallic profiles of the " H " or " l " type comprising a web and two legs each consisting of two half-legs, said process making use jointly of telemetry and the shadow technique and according to which, considering the web on the horizontal, a) the position and the orientation of one surface of the web is determined by performing a distance measurement by telemetry, in particular by optical triangulation, for two points at least situated in different places on the width of said surface, and characterized in that : b) the height of one end of a leg is determined, on the one hand, by transmitting between the two legs a bundle of rays directed toward the inner surface of the leg in such a way that the bundle is partly intercepted by said surface, the other part spreading beyond the end of the leg whose height is being determined and, on the other hand, by detecting, on the other side of the leg, the position of the point of transition between the zone illuminated by the bundle and the zone not illuminated thereby, c) the position and the orientation of said leg is determined by performing a distance measurement by telemetry, in particular by optical triangulation, for two points at least situated at different levels on the outer surface of said leg, d) and the width of the half-leg corresponding to the leg for which the height of the end was determined is calculated on the basis of the data gathered in operations a), b) and c) above.

Description

PE NON-CONTACT DIMENSIONAL MEASUREMENT PROCESS OF KETALLIC BEAMS

AND APPARATUS FOR IMPLEMENTATION

The present invention relates to a non-contact dimensional measurement method of metal beams and an apparatus for carrying out this method.

The beams (here denoted by this term the "H" and "I" sections) are generally implemented by being joined to one another, for example, by welding or bolting. These two kinds of assembly impose tight dimensional tolerances of the beams during their manufacture by rolling. However, this rolling operation can cause dimensional defects, for example, in the following manner: During the rolling of the beams in a universal cage, the widening of the wings being left free, the symmetry of the profiles 'n' is not assured enough. The table and the tools. Of the universal cage input play an important role for the adjustment of this symmetry. However, due to the inaccuracies in the width of the wings 20 of the initial blanks and the fact that this width increases with each pass, the table of rollers bringing the beams to the cage is not necessarily adjusted to a position making it possible to engage the beam symmetrically. For the same reason, faults. dimensional 'beams cannot be completely corrected by the finis-25 seuse cage.

However, the beams are implemented in the state at the exit of the rolling installation, without any additional operation being able to correct any dimensional defects. If these are identified later, for example during the mounting of the metal frame 30 of a building, it is sometimes necessary to stop the construction to »replace the non-conforming beams. :;

We therefore understand the need to perform an exact dimensional measurement of the beams at the rolling mill, either in order to classify them according to their dimensional accuracy before sending them to the customer, or 55 to be able to intervene in correction by adjusting the parameters of rolling mill market.

The aim of the present invention is to solve the above problems by means of a non-contact dimensional measurement technique of metal beams.

40 For this purpose, the subject of the present invention is a method of dimensional measurement without contact of metal beams, of the type of those profiled of "H" or "I" comprising a core and two wings, characterized in that that it consists, the soul being considered horizontally: a) in determining the level in height of one end of a wing, 5 on the one hand, by emitting between the two wings a light beam directed towards the inner face of the wing so that the beam is partially intercepted by said face, the other part propagating beyond the end of the wing whose level is determined, and, on the other hand, in detaching, on the other side of the wing, the position of the transition point between the illuminated area and the area not lit by the beam, b) determining the position and orientation of said wing by making a measurement of distance by telemetry, in particular by optical triangulation, for at least two points located at different levels on the outer face of said wing, 15 c) determining the position and orientation of one face of the core ^ by carrying out a distance measurement by telemetry, in particular by optical triangulation, for at least two points situated at different locations over the width of said face, d) and to calculate, from the data collected in operations a), b), and c) above, the width of the half-wing corresponding to the end whose height level has been determined.

It is also possible, by reproducing operation a) above for the two ends of the same wing and by carrying out operation b) on said wing, calculate the width of the latter.

Similarly, by reproducing operation c) for the two faces of the core, the thickness of the latter can be calculated. Of course, one can also know the thickness of the core from the characteristics of the beam cage.

The invention also relates to an implementation device.

30 of the method and which comprises: „- at least one light emitter-receiver pair (5, 12), the emitter of which is disposed between the two wings (3, 4) of the beam (1) and emits a beam light directed towards the inner face of a half-wing (3a) so that only part of the light beam 35 is intercepted by the latter, the other part propagating beyond the end (E.) of the 'wing ; and whose receiver (12) is arranged in f ** T? Λ- 3 glance from the transmitter (5) on the side of the outer face of the wing (3) and delivers a signal representative of the height level of the transition point between the illuminated area and the area left in the shade of the half-wing (3a), 5 - telemetry means (14, 14 '), in particular by optical triangulation, for determining the position and orientation of said wing (3) by light reflection on the external face of the 'wing at least two points (Aj, A'j) offset over the width of said face, -. ^ - telemetry means (16, 16 '), in particular by optical triangulation, for determining the position and orientation of a face of the file t (2) by light reflection on said face at least, two points (Bp E ^) offset over the width of the core (2) - and an electronic processing system to calculate ', from the signals from the transmitter-receiver pair (5, l £), and means of 15 telemetry (14, 14 ') and (16, 16'), the width of the. ^ Half-wing placed between the transmitter (5) and the receiver (12).

Thanks to the invention, it is possible to know the exact dimension of each constituent part of the profile, as well as their relative positions, and this without requiring contact with the product. It is then easy to classify the beams according to their dimensional and / or conformational accuracy with a view to their dispatch there. customer base. We can also act to correct faults detected in. intervening on the adjustment of the working parameters of the rolling, either .. for the next beam, or for the same one whose 1 faults have been detected.

The invention will be better understood and other characteristics and advantages will emerge more clearly in the light of the description which follows, given with reference to the appended drawings which schematically represent, and only by way of example, embodiments of the invention, in which: OJ FIG. 1 shows the principle of the dimensional dimension of the parts of the profile defining an "H" beam., -auivbnt an embodiment of the method according to the invention. - ,!

FIG. 2 schematically represents the calculation of a width of a half-wing of the beam. : · 55 Referring to Figure 1, a beam 1 profiled in "H" moves towards the observer on a line of transfer rollers (not shown in the figure) which is at the exit of the cage finisher. The beam 1 consists of a core .2 connecting in their y, j middle two wings 3 and 4 which are in principle perpendicular to the core 2.

4

As can be seen, the latter being horizontal, the operation of the dimensional measurement of the width of the half-wings according to the main embodiment of the method according to the invention consists of c '^ s sequences a), b ), c) and d) defined above and explained in detail 5 in the following:. . '* a) Determination of the height level of the end of the siles.

To determine the position of the ends, on the one hand, of the wings, two light-emitting units 5 and 5 'are arranged between the wings 3 and 4, one above the other, providing between them a 3p passage for scrolling of beam 1.

* The transmitting units 5 and 5 'are mounted respectively on a chassis 6 and a lower frame 6' both fixed and each unit emits a light beam towards the inner faces of the wings 3 and 4. The two transmitting units 5, 5 'are identical to each other. Each is formed by a vertical tubular element 8, (8 ') channeling the light from a point source 7, (7'), placed at a closed end of the element B (for example a filament electric bulb) up to 'to an optical unit 9, (9') placed between the wings and mounted at the end of the element 8. This optical unit is a hollow body provided on its side wall with two 'openings 20 18, 19 (18' , 19 ') each facing the inner surface of a wing of the beam. The interior cavity of the block is equipped with two light deflectors 10, 11 (10 ', 11') placed behind each of the two lateral openings. Each deflector has an orientation on the vertical such that the lunar which it receives from the source 7 (7 ') is deviated "through a lateral opening 18 or 19 (18' oll19 ') in the direction of the interior surface Preferably, the deflectors 18, 19 (18r, 19 ') are diffusing rather than reflecting surfaces so as to emit a beam of rays which are parallel or at least substantially parallel towards the wings of the beam.

? 0 As can be understood, each transmitting unit 5, 5 ′ therefore groups together two transmitters each intended for one of the opposite half-wings 3e, 4a (3b, 4b) constituting two by two (3a, 3b and 4a, 4b) of the two wings 3 and 4 of the profile. . · R <

As can be seen in FIG. 1, each light beam coming from a lateral opening (18, 19, 18 ', 19') is partially overshadowed by the inner face of the half-wing (respectively 3a, 4a, 3b, 4b) towards which it is directed and the non-intercepted part of the beam propagates beyond the end of each half-wing.

39 f On the other hand, four optical receivers 12, 12 'and 13, 13', 5 identical to each other, are arranged in the path of the non-intercepted part of the light beams. These receivers include a conventional optic symbolized in the figure by the double small vertical arrows not referenced and in the image plane of which has been placed a photosensitive element capable of delivering a signal representative of the height of the place of transition between the area illuminated by the beam on the receivers and the area kept in the shadow of the half-wing. The receivers to be used can advantageously be receivers with a linear array of photodiodes of a type already known per se and available commercially, for example under the brand "RETICON type 1024 H20".

b) Determination of the position and orientation of a wing.

For this determination, an optical triangulation is carried out for at least two points on the outer face of the wing concerned, these two points being offset on different levels in height. Since the principle of optical triangulation is already known per se, it is unnecessary to describe it in detail here.

In order to perform optical triangulation, a projector-detector pair is used for each point to be measured. To this end, four projector-detector pairs 14, 14 'and 15, 15' are arranged opposite 20 of the outer faces of the wings 3 and 4. These four pairs are paired two by two and each of the two pairs (14, 14 ' and 15, 15 ′) thus formed, is assigned to one of the two wings of the beam 1 so as to be able to determine the position of two points on the external face of each of these. Each pair of optical projector-detector is represented by a simple block in FIG. 1 so as not to overload it unnecessarily.

The detectors deliver electrical signals representative of the position of points A ^, A '^ and A ^, A' ^ (Figure 2) relative to a reference chosen in advance. This reference can be obtained by any suitable well-known means, for example using an initial JO calibration by a false beam serving as a gabari. The same reference zeroing technique can of course be used with respect to the transmitter-receiver pairs 5, 5 ′ seen above.

c) Determination of the position and orientation of a face of the core.

J5 For the determination of the position and the orientation of a face of the same 2, for example the upper face, an optical triangulation is carried out for two points and B £ on the upper face of the core offset according to the width thereof. For this purpose, two pairs of t-spotlights j9 optical detectors 16 and 16 'are fixed to the chsssis 6 above the

'-V

V

6 beams.

The receivers of these optical pairs deliver electrical signals representative of the position of the points and on the upper face of the core 2.

5 According to one embodiment of the invention, an optical triangulation is carried out for only one point on the other face of the core, in this case on the lower face in the example considered, in order to determine from signals thus delivered, the thickness "e" of the core.

To this end, a pair of headlamp-optical detector 17 is arranged in relation to the underside of the core 2. The detector of this optical torque delivers an electrical signal of the position of the point on the underside of the core. .

d) Calculation of dimensions from signals.

For the determination of the dimensions of the beam, one can use an electronic processing system, for example a microprocessor which is associated with the optical receivers and detectors mentioned above.

Referring to FIG. 2, the calculation operations are as follows: 20 - the signals supplied by the linear receivers 12, 12 'and 13, 13' make it possible to determine the respective positions of the points Ej, and E ^, E * 2 respectively representing the ends of the wings 3 and 4. In the example considered, these positions are defined by the dimensions h ^, h'j and l · ^, h12> of Ej, E '^ and E2, E'2 respectively with respect to a reference plane 25 which may for example be the surface of the frame 6 ′ * represented by the axis ff. (This reference system is preferred here to the calibration by gabari mentioned above, only to better understand the invention using Figure 2).

- the signals provided by the optical triangulators 14, 14 'and 50 13, 15' allow the determination of the points A ^, A '^ and A12 and * consequently give the position and the orientation of the lines d ^ and d ^, representative of the outer face of the wings 3 and 4.

In the same way, using the triangulators 16 and 16 ′, the position and the orientation of the line 11 ′ representative of the upper face of the core 2 are determined.

From this information, it is easy to determine the position of the point of intersection of the lines and 11 '. The position of Ej being defined, the measure dj of the segment C ^ Ej is determined, characterizing the width of the upper half-wing 3a.

V

7

An identical calculation is carried out for the other three half-wings 3b, 4a and 4b.

The total width of the wing 3 is obtained in the same way, by locating the level of the ends E ^ and E '^ of the wing and of the straight line 5 al a'r

The same operation is carried out for the calculation of D2, measurement of the length of the segment E2 E'2 characterizing the width of the wing 4. Furthermore, the determination of the lines dj and d ^ and the knowledge, by the adjustment parameters rolling, thickness "a" of the wings,. 10 'easily allows the need to calculate the field width between the two wings at whatever level you want.

Regarding the thickness "e" of the core 2, there are two ways of calculation.

First, the thickness "e" can be calculated from the data supplied by the rolling stand, as for the thickness of the wings mentioned above.

According to another embodiment of the invention seen previously, the thickness "e" of the core 2 can be calculated from the position of the three points B ^, B2 and B ^, the upper and lower faces of the soul 2 20 being considered to be parallel to each other. Knowing the position of a single point on the underside then allows the calculation of the distance separating the two faces of the core, that is to say, the thickness ne ”

G

With this thickness "e", one can easily calculate the width 25 of x and d 'of the two lower half-wings 3b and 4b, that is: of i = - d1 - e and of 2 = D2 - d2 - e

This method of proceeding, using the width of the wing and the thickness of the web to determine, from the width of a half-wing, the width of the complementary half-wing, constitutes a variant of implementation. work of the invention. It differs from the implementation described above residing in a repetition of the elementary method of calculating a half-wing, by the fact that only three couples (16, 16 ′ and 17 of optical triangulation attached to the core of the beam are necessary and not 35. The advantage lies in particular in the smaller size of the measuring device as well as in the economy of a projector-emitter pair.

It should be emphasized however that this variant is based on '39 the assumption that the two faces of the core are parallel, which is t' • Λ 8 moreover generally the case.

The method according to the present invention allows an exact and contactless dimensional measurement of the beams and finds wide applications in the metallurgical field.

5 It goes without saying that the invention has been described and represented for purely explanatory purposes, in no way limiting, and that various modifications of detail, variants or equivalents could be made without departing from the scope of the invention in the to the extent that the features set out in the appended claims are met.

10 * In particular, it is possible to double the number of pairs of optical triangulation assigned to the wings of the beam, a pair of pairs being intended for a position measurement of two light points on each half-wing. Such a variant, corresponding to the most complete implementation of the invention known to the inventors, makes it possible to determine with the desired precision the dimensional characteristics of the beams in the case where the wings are not planar but are profiled in V.

It should also be noted that the contactless measurement technique according to the invention, combining a method of telemetry by optical triangulation with a method of shadow by partial masking of linear arrays of photosensitive elements, is not new in itself. .

However, the systems known in this regard, such as for example that described in Belgian patent No. 46826, do not have the level of performance achieved by the invention. In particular, this has advantages, notably linked to the design of the transmitting units 5, 5 ′ and to their location between the wings, which are not found in the state of the art and which will not escape the skilled person.

ï T.

_i_ ^ * JS y - f.,. , j · **

Claims (6)

9 1. Non-contact dimensional measurement method of metal beams, of the type of those profiled in "H" or in "1" comprising a core and two wings, characterized in that it consists (the core being considered in horizontal): a) to determine the level in height of one end of a wing, on the one hand, by emitting between the two wings a light beam directed towards the inner face of the wing so that the beam is 10 partially intercepted by said face, the other part propagating beyond the end of the wing whose level is determined, and, on the other hand, by detecting, on the other side of the wing, the position of the transition point between the lighted area and the area not lit by the beam, b) determining the position and orientation of said wing by carrying out a distance measurement by telemetry, in particular by optical triangulation, for at least two points located at different levels on the outer face of said wing, c) to be determined the position and orientation of a face of the core by carrying out a distance measurement by telemetry, in particular by optical triangulation, for at least two points situated in different places on the width of said face, d) and calculating, from the data collected in operations a), b), and c) above, the width of the half-wing corresponding to the end, the height of which has been determined. 2) Method according to claim 1, characterized in that the operation a) is repeated for the other end of said wing and the width of the complementary half-wing is calculated. 3. Method according to claims 1 or 2, characterized in that the operation a) is repeated for one of the ends of the other wing and the operation b) is repeated for this other wing and one calculates the width of the half-wing corresponding to said end. 4. Method according to claim 3 characterized in that the operation a) is repeated for the other end of the wing and the width of the complementary half-wing is calculated. 35 3) Method according to any one of the preceding claims, characterized in that the thickness of the core is calculated by determining, by optical triangulation, the position of a point only on the face of the opposite core to the one where operation c) was carried out. . 39 6) apparatus for implementing the dimensional measurement method i ′ k 10 of the beams according to one of claims 1 to 5, characterized in that it comprises î - at least one light emitter-receiver couple (5, 12) whose transmitter is disposed between the two wings (3, 4) of the beam (1) and 5 emits a light beam directed towards the inner face of a half-wing (3a) so that only part the light beam is intercepted by the latter, the other part propagating beyond the end (E-.) of the wing; and the receiver (12) of which is arranged opposite the transmitter (5) on the side of the outer face of the wing (3) and delivers a signal representative of the level in height of the place of transition between the illuminated area and the area left in the shadow of the half-wing (3a), - telemetry means (14, 14 '), in particular by optical triangulation, to determine the position and orientation of said wing (3) - 15 by light reflection on the outer face of the wing at at least two points (A ^, A'j) offset over the width of said face, - telemetry means (16, 16 '), in particular by optical triangulation, for determining the position and orientation of a face of the core (2) by light reflection on said face at at least two points (B ^, 20 f ^) offset over the width of the core (2) - and an electronic processing system to calculate, from the signals from the transmitter-receiver pair (3, 12), and telemetry means (14, 14 ') and (16, 16'), the width of the d emi-wing placed between the transmitter (5) and the receiver (12). 7) Apparatus according to claim 6, characterized - in that it comprises four pairs "transmitter-receiver", whose transmitters arranged between the wings (3, 4) of the beam are grouped in pairs, forming transmitting units ( 5, 5 '). These two pairs being placed opposite one above the other, providing 50 between them a passage for the passage of the web (2) of the beam, and whose receivers (12, 12 ', 13, 13 ') are each arranged opposite a half-wing (3a, 3b, 4a, 4b) of the beam, in that it comprises at least four telemetry means (14, 14', 15, 15 ') arranged two by two opposite each wing of the beam, and in that it comprises at least three telemetry means (16, 16 ', 17) two of which (16, 16') are arranged opposite a face of the core (2) and at least one of which (17) is disposed opposite the other face 29 of the core (2). v _ 11 8. Apparatus according to claim 7, characterized in that eue the telemetry means disposed opposite the wings of the beam are eight in number, said means being grouped in pairs, a pair being arranged opposite each half-wing of the beam. 5 9) Apparatus according to claim 7 characterized in that each light emitting unit (5, 5 ') is constituted by a vertical tubular element (8) closed at one end, comprising at its closed end a light source (7) and provided at its other end located between the wings with an optical unit (9) having lateral openings (18, 19) opposite 10 of each of the beams' wings and fitted internally with two inclined light deflectors (10, 11) vertically so as to deflect the light received from the source (7) through the lateral openings (18, 19) towards the interior surface of the beams' wings. * <15 10) Apparatus according to claim 9, characterized in that the deflectors (10, 11) are provided with diffusing surfaces. 11. Apparatus according to claims 7 or 9 characterized in that the light receptors (12, 12 ', 13, 13') comprises photosensitive elements constituted by linear arrays of photodiodes 20 aligned in the vertical. / f